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More Rust In LouisianaAsian soybean rust has been found on kudzu in Iberia and St. Mary parishes in Louisiana, the second occurrence in the state during the 2007 season. The first confirmation for 2007 was in Iberia Parish on May 8 (see "Louisiana’s First Rust Of 2007 Season Comes Early" in the section.
According the state’s commentary on USDA’s Pest Information Plantform for Extension and Education (PIPE) Web site, the "incidence and severity are low (in Iberia Parish), initially, but spread has occurred from the initial find of 10 feet in diameter to 200 feet to 250 feet. Sampling at the initial site revealed 11 of 14 sampling sites within that 250 feet were positive for Asian soybean rust." The confirmation was made June 5.
The commentary also notes that soybean rust was confirmed in St. Mary Parish in kudzu on June 5. The finding is being watched very closely because of its proximity – just 30 feet -- to a soybean field.
Due to continuing scattered showers in the area, conditions for Asian soybean rust are favorable.
To access the PIPE Web site, visit http://www.sbrusa.net
Sources: The USDA Pest Information Platform for Extension and Education (PIPE) Web site and USDA’s National Soybean Rust Alert e-mail.
Amy Fahnestock, Jun 05 2007, 22:46Domark, Stratego OK’dThe list of Asian soybean rust-approved fungicides keeps getting longer. EPA has awarded full Section 3 approval to Stratego from Bayer CropScience and Domark 230, manufactured by Isagro and distributed by Valent U.S.A. Corp.
Both had previously received Section 18 Emergency Exemptions for use in soybeans for Asian soybean rust. They also are approved for a number of other soybean diseases.
Stratego can be used as part of Bayer CropScience’s Plant Health program to improve overall crop health and increase yield potential. A premix of strobilurin and triazole chemistries, its two different modes of action inhibit spore germination on the plant surface and fungal growth within plant tissues.
Domark 230, which contains the active ingredient tetraconazole, can be used as both a preventative and curative treatment for soybean diseases, protecting existing and new growth.
It will help growers achieve Maximum Harvest Value, a combination of disease protection, ease of harvest, and crop safety to maximize yields, according to Valent.
Amy Fahnestock, Jun 05 2007, 22:09Iowa Soybean Rust Find Mystifies OfficialsHow and why a single leaf infected with Asian soybean rust was found in Iowa in March are questions that continue to be addressed by federal investigator, according to the Iowa Department of Agriculture and Land Stewardship (IDALS).
Officials with IDALS and Iowa State University (ISU) have found no further evidence of Asian soybean rust in the field where the leaf was reported to have come or in neighboring fields.
"We did verify that one leaf submitted in a plant sample was infected with Asian soybean rust, but how it got into Iowa still needs to be determined," says Bill Northey, Iowa Secretary of Agriculture. "After careful examination of the materials collected to date, we believe no Asian soybean rust infection occurred during the 2006 growing season in Iowa."
After analyzing additional plant materials and finding no evidence of rust, IDALS and ISU officials determined that it warranted further investigation by the USDA’s Office of Inspector General. "We take the discovery of any new plant pathogen very seriously, especially one that would be the first recorded occurrence in Iowa, " says Northey.
On March 8, a sample was submitted to ISU’s Plant Disease Clinic. The sample was made up of soybean seeds and plant debris — pieces of pods, stems, and a leaf. The sample was reported to have been taken from a bin of soybeans harvested in Mahaska County in 2006. ISU’s testing revealed infection by Asian soybean rust. On March 12, USDA confirmed that the single leaf in the sample was infected with the disease.
On March 13, personnel from IDALS and Iowa State collected additional samples of seed and plant materials from bins at the location where the sample was allegedly collected. They analyzed the samples and found no symptoms or signs of Asian soybean rust.
IDALS and ISU personnel extensively collected remnants of leaves from the field where the submitted sample reportedly was harvested, as well as from adjacent fields. Although many leaves had symptoms of a common soybean foliar disease called frogeye leaf spot, the officials found none had symptoms or signs of Asian soybean rust.
IDALS contacted the USDA’s Office of Inspector General, which now is leading the investigation into the origin of the infected leaf submitted to ISU.
In March, when the infected leaf was discovered, the Iowa Soybean Rust Team — which includes representatives of IDALS, ISU, the Iowa Soybean Association, and USDA’s Animal and Plant Health Inspection Service — pointed out that it did not pose a risk for the 2007 growing season. The fungus and spores that cause the disease cannot survive an Iowa winter, plus they require green leaf tissue to sustain themselves.
As in previous years, producers need to continue to be vigilant and monitor conditions that favor rust. They should consult with ISU Extension specialists on identification and management plans and work with the Iowa Soybean Rust Team’s First Detectors to positively identify any suspected soybean rust in their fields.
First Detectors are the more than 600 agribusiness professionals from across Iowa who were recruited and trained by the Iowa Soybean Rust Team. They can examine leaf samples and decide whether they warrant further analysis by ISU Extension personnel or faculty scientists to detect possible infection.
Growers are encouraged to consult with Iowa Soybean Rust Team First Detectors if they suspect plants might have soybean rust. There is no charge. Names and contact information for First Detectors are available on the Iowa Soybean Rust Team’s Asian Soybean Rust Web site, http:// www.soybeanrust.info, and at county ISU Extension offices.
Asian soybean rust was first reported in the continental U.S. in 2004. So far, the disease has mostly affected Southern states, although the disease has been found as far north as Illinois and Indiana. In order to infect Midwestern soybeans, ISU scientists such as XB Yang say viable spores must blow in from the Gulf Coast states (Florida to Texas) and arrive when there are cool, moist conditions. ISU has planted 20 sentinel soybean plots around Iowa, which is part of a national sentinel system stretching from Florida and Texas up through the Midwest. The plots are monitored throughout the season and producers will be informed of any threat.
Source: Iowa Department of Agriculture and Land Stewardship press release
Amy Fahnestock, May 23 2007, 11:43Soybean Rust Popping Up In AlabamaHere’s an update on the Asian soybean rust status in Alabama from Ed Sikora, Auburn University plant pathologist. He also comments on a recent trip to Mexico.
"Soybean rust was detected on a fourth kudzu patch in the city of Montgomery. This is a new site in the county. The patch was approximately 20 feet by 20 feet square and contained old and new infected leaves. All 31 leaves collected and examined were infected with soybean rust, which was actively sporulating. The overwintering site is in a protected area below a section of interstate highway across from a residential area.
"This is the fourth Asian soybean rust-infected kudzu patch found in Montgomery this year, but the first site in this city that was not also detected last year. We have tried to destroy the other three sites in Montgomery by removing all green leaf tissue. Two of these sites have not grown back, but the third patch is coming back strong.
"Soybean rust-infected kudzu patches have also been located in Dothan in Houston County in southeast Alabama and in Baldwin and Mobile Counties in southwest Alabama.
"We have also found non-soybean rust-infected old kudzu leaves in Andalusia, and non-infected new kudzu growth in Repton. These towns are located north/northeast of the Baldwin/Mobile County areas.
All kudzu patches inspected north, west, and east of Montgomery County are still dormant.
"On another note, I visited Chiapas, Mexico to scout for Asian soybean rust with Dr. Arcenio Gutierrez-Estrada in late January. Dr. Gutierrez had four soybean sentinel plots in the main soybean production area for Chiapas on the south coast. No rust was detected last year.
"During my trip we visited highlands, lowlands, wetlands and drylands but found no soybean rust. We looked at black bean fields at harvest and a lot of leguminous vines both in and mostly out of the urban areas. Soybeans are not in production currently and no volunteer soybeans were observed. Dr. Gutierrez will be planting at least four more sentinel plots later this year."
Source: E-mail update from Don Hershman, University of Kentucky
Amy Fahnestock, Feb 09 2007, 19:33Leaf Damage Factors Into Rust Yield Loss(Editor’s note: A condensed version of this article has been published in the February 2007 issue of CropLife® magazine on page 42.)
Damage the soybean leaf, damage the plant’s yield. This is a vital piece of information that Saratha Kumudini and her international research team didn’t have in hand when they first set out to develop a yield loss prediction model for Asian soybean rust.
Kumudini, a University of Kentucky crop physiologist, and her team already knew that defoliation and growth stage were factors in yield loss. What they’ve now determined is that damaged leaves can greatly impact the soybean plant’s ability to absorb radiant energy, and that in turn, reduces yields.
This particular research project has been a recent focus in CropLife® magazine’s Rust Research Series (see "New Tool On The Horizon," September 2006 CropLife, page 15 and "New Web Site Features International Project," RustReady.com, News, dated July 17, 2006). Members of the team also hail from Brazil and Louisiana State University.
Measuring Lesions Provides Results
When the research began in Brazil in 2005, the group tried mimicking the defoliation to, in turn, mimick the disease, but this practice didn’t give them a good one-to-one correlation with the actual yield losses from infected fields. What did work, however, was adding in the measurements they took of the amount of necrotic lesions from soybean rust on leaves still attached to the plant. Using a healthy area leaf index, which accounted for both the necrotic lesions and defoliation, the team ended up with much closer results between their test plots and plots with soybean rust.
"We didn’t want to stop there, we wanted to know if there was a one-to-one correlation between necrotic lesions and plant productivity, so we went to Quincy, FL," Kumudini says. "What we were looking for were leaves with the necrotic lesions and its impact on the plant’s photosynthetic capacity-productivity level."
Field work included looking at leaves in the fields, finding the lesion, and taking a photosynthesis measurement of the plant’s ability to take radiant energy and turn it into biomass.
"The point is that when we look at these plants with necrotic lesions, those lesions have a bigger impact (on photosynthetic capacity) than what you can see visually," Kumudini said.
Based on their first year of data, the scientists believe that soybean rust-induced yield loss is dependent on growth stage, defoliation, and the lesions on the intact leaves.
Project Continues To Develop
"So what we are doing in Kentucky and Louisiana is developing a yield loss prediction model that looks at healthy leaf area and relates healthy leaf area to yield," she said. "We are looking at different maturity groups, different row widths, and saying can we develop a valid yield loss model. Right now, we are in the model development stage."
The yield loss model will be used to develop an interactive software tool that would determine the grower’s yield potential and the predicted yield loss if rust should defoliate or damage the leaves of the crop.
The model would allow a grower to weigh the potential yield loss against the cost of fungicide applications to make sound management decisions.
Additional research will be conducted this year. The team hopes to have a yield-loss prediction model ready for use within two to three years.
Source: University of Kentucky press release
Amy Fahnestock, Feb 06 2007, 15:57Asian Soybean Rust Team Earns Highest National Honor Award For EffortsAgriculture Secretary Mike Johanns recognized the Asian Soybean Rust Team — made up of employees from various USDA branches and University Extension leaders — for exemplary service and achievements during the 59th annual USDA Honor Awards Ceremony on Oct. 20 in Washington, DC. Their outstanding work was done while participating in interagency and interdepartmental collaborations.
"Through teamwork and leadership, individuals and agencies across USDA averted disaster by using a science-based strategy to address and recover from the entry of Asian soybean rust which is a potentially devastating disease," Johanns said. "About 70% of the nation’s soybean growers use this Web-based risk management system and made critical decisions based upon the information that was provided."
The Asian Soybean Rust Team was recognized for planning, rapid response and recovery of a potential disaster that was averted by using science-based and technological strategies or addressing and mitigating risks for Asian soybean rust, a potentially devastating plant disease.
The team is comprised of individuals from USDA’s Animal and Plant Health Inspection Service, Agricultural Research Service, Economic Research Service, Cooperative State Research, Education and Extension Service (CSREES), and the Risk Management Agency, as well as plant pathologists from several land-grant universities.
Led by Coanne O’Hern of APHIS, the universities were represented by: Anne Dorrance, The Ohio State University; Don Hershman, University of Kentucky; James Vankirk and Roger Magarey, North Carolina State University; Julie Golod and Scott Isard, Pennsylvania State University; Carla Thomas, University of California-Davis; Sue Ratcliffe, University of Illinois; and XB Yang, Iowa State University.
Marty Draper, currently CSREES national program leader, was also recognized for his work on the team while representing South Dakota State University.
CSREES national program leaders Kitty Cardwell and William Hoffman represented the nine CSREES employees on the team.
"CSREES is proud of the contributions our employees have made in advancing agriculture," said Gale Buchanan, USDA under secretary for Research, Education and Economics. "Their vision, leadership, and commitment to their work is deserving of the honor they have received from the Secretary."
Since the discovery of soybean rust in the United States in 2004, the team has been working tirelessly to prepare farmers for the arrival of the disease.
The following are some research and Extension education contributions made to soybean rust effort:
- The establishment and monitoring of sentinel plots. The U.S. soybean-producing states house sentinel plots — 50-by-50-foot areas of early-planted soybeans intended as the first line of defense in detecting soybean rust. The plots that dot the agriculture landscape are the first place researchers and Extension educators go when soybean rust threatens a state.
- The Pest Information Platform for Extension and Education, http://sbrusa.net. Managed by USDA’s Animal and Plant Health Inspection Service (APHIS), the site was launched to monitor the occurrence and movement of soybean rust throughout the country using real-time data based on the sentinel plots. The Web site is now also used to track the movement of soybean aphids.
- "Using Foliar Fungicides to Manage Soybean Rust" fungicide manual. This 60-page booklet, designed to help walk a grower through soybean rust management and proper fungicide applications, is a multi-state, multi-organizational effort that covers such topics as a soybean rust overview, making fungicide decisions, fungicide basics, application basics, aerial application tips, bee toxicity, and an overview of similar diseases. The publication contains articles, illustrations, photographs, maps, tables, and charts, contributed by the nation’s leading land grant universities’ plant pathologists, as well as experts from Canada. Ohio State, South Dakota State University, and the University of Kentucky have led the effort in developing and editing the booklet.
- Soybean rust ID card. "Identifying Soybean Rust," funded through soybean check-off dollars and federal grants, is the result of a collaborative effort between USDA, the Ontario Ministry of Agriculture and Food, and 22 land-grant universities. The free pocket-sized card, printed in both English and Spanish, outlines soybean rust symptoms and differences to similar-looking foliar diseases, such as bacterial blight, bacterial pustule, downy mildew, Frogeye leaf spot, and brown spot.
- Educational efforts on the use and storage of foliar fungicides labeled for soybean rust. Through applied research efforts and effective monitoring of soybean rust throughout the country, Extension Educators have successfully educated growers on the proper use of fungicides, and whether or not they are necessary during a given growing season. For example, as a result, Ohio farmers have saved an average of $15-$18 an acre on fungicide costs — $70 million in total savings to the state’s soybean industry.
The Honor Awards are the most prestigious awards presented by USDA. This year there are 34 individual and group award winners. They are being honored for outstanding service in many fields, including stewardship of natural resources, scientific research, animal and plant disease control, environmental innovations, education outreach, emergency response to disasters, food safety, farm and food program delivery, trade and export development, and rural economic development. USDA also honored employees who had performed individual acts of heroism and courage.
CSREES advances knowledge for agriculture, the environment, human health and well-being, and communities by supporting research, education, and Extension programs in the Land-Grant University System and other partner organizations. For more information, visit http://www.csrees.usda.gov
Sources: The Newsroom page of USDA’s CSREES Web site,
http://www.csrees.usda.gov and The Ohio State University’s News and Media Relations e-news release
Amy Fahnestock, Oct 24 2006, 16:37Indiana: No Reason For Concern About Nearby Soybean RustIndiana soybean farmers have no reason for concern over this week’s confirmed cases of Asian soybean rust in Kentucky and Illinois counties, says Greg Shaner, a Purdue University Extension plant pathologist.
"There is no risk for this year’s Indiana soybean crop," Shaner says. "There’s very little green leaf material remaining for rust to infect. Even though rust made it into Kentucky and Illinois and rust spores might have gotten into Indiana doesn’t mean anything for next season, either."
Soybean rust was confirmed in the western Kentucky counties of Caldwell, Christian, Fulton, Hopkins, Lyon, Marshall, Todd, and Union, and Pope County in southern Illinois. The northernmost county on that list — Union — borders Posey County in southwest Indiana.
Soybean rust is a foliar disease caused by the fungus Phakopsora pachyrhizi. The fungus forms tan lesions on soybean leaves. Infected leaves die and fall off, severely limiting the soybean plant’s ability to produce seeds. In extreme cases, the disease can wipe out 80 percent of a soybean field’s yield potential.
Rust was first found in the continental U.S. in Louisiana in November 2004. Since that time, the fungal disease has infected soybean crops mostly in the far South.
Fungal spores spread by wind and then infect soybeans, kudzu, and similar legumes. The Union County, KY, infection is believed to be the farthest north the disease has been found.
Working in Indiana’s favor is soybean rust’s inability to survive the winter, Shaner says. The disease needs green leaf tissue to remain viable. Most leaf tissue capable of allowing rust to overwinter is in Gulf Coast states, meaning that the disease must make the long journey north each year.
"Many of the soybeans here have already been harvested or are mature enough that no green leaves remain," Shaner says. "Even the kudzu we have in Indiana will die back in the winter, giving rust no overwintering host."
Although rust poses no threat in Indiana this year, farmers are encouraged to send suspicious soybean or kudzu leaves to Purdue’s Plant and Pest Diagnostic Lab (P&PDL) for analysis, says Gail Ruhl, the lab’s co-director.
"Confirmation of rust in Indiana at this late date would still provide valuable information to scientists who are working on predictive models for this disease," Ruhl says. The $11 P&PDL sample handling fee will be paid by funds provided by the Indiana Soybean Board and the National Plant Diagnostic Network, she adds.
For more information about soybean rust, visit USDA’s Pest Information Platform for Extension and Education (PIPE) Web site at http://www.sbrusa.net. Producers also can download or purchase Purdue Extension publication ID-324, "Preparing for Asian Soybean Rust." Single copies of the publication can be ordered for $2 or packages of 25 for $5.
Sources: Oct. 13, 2006 Purdue University press release written by Steer Leer. Greg Shaner can be contacted at 765-494-4651, shanerg@purdue.edu and Gail Ruhl at 765-494-4641, rulhg@purdue.edu
Amy Fahnestock, Oct 16 2006, 20:43Soybean Rust Numbers Rising In The SouthThe Asian soybean rust-affected counties in South Carolina just keep adding up. The soybean disease has now been identified in 10 counties altogether, putting it just behind Florida’s 13 affected counties in 2006.
Added to the casualty list on Sept. 9 were Anderson, Calhoun, Colleton, Dorchester, Hampton, Horry, Lee, and Sumter counties. Previously documented were Florence County on Sept. 7 and Orangeburg County on Aug. 31. The confirmation in Calhoun County is the second; the first was on Aug. 21.
Louisiana reported a new rust find in a commercial soybean field in Catahoula Parish on Sept. 7. Several new confirmations in Georgia kudzu also were reported last week. Currently, there are a total of 45 counties in seven states that have rust infections in either soybeans or kudzu.
"Asian soybean rust is now beginning to crank in the Deep South,"
says Don Hershman, University of Kentucky Extension plant pathologist, who also serves as Southern Region coordinator for the North Central Soybean Research Project.
According to John Mueller, Clemson University Extension plant pathologist, "In the last week we have identified rust in several new counties in South Carolina. All of the finds except Dorchester County were located at Maturity Group 5 sentinel plots (Orangeburg was in Maturity Group 4 and 5 sentinel plots). I would characterize all of the finds as relatively light in severity except Horry, Orangeburg, and Sumter counties, which had slightly higher levels of rust."
The highest initial levels of severity were found in samples collected on Sept. 6 from the Maturity Group 5 Sentinel plots off of Highway 521 South near the Sumter/Clarendon County line in Sumter County. "Seven out of 50 leaves had rust present," Mueller says. "Two of the leaves had greater than 50 pustules per leaf, one of the leaves had 20-plus pustules, and the remaining four leaves had five to 10 pustules per leaf. No rust was seen in the Maturity Group 4 sentinel plots in Sumter.
"Rust is widespread enough in the state that anyone with soybeans in the R4 to early R5 stage should consider spraying with a fungicide," Mueller says. "Since rust seems to be established in a wide area the use of a triazole to help eradicate the rust that is already present is warranted. If controlling foliar, pod, and stem diseases is also an objective, the triazole needs to be combined with a strobilurin.
"Many growers are combining their fungicide sprays with an insecticide for stink bugs," Mueller adds. "This appears to be a very good idea in many areas. Dr. Sullivan reports that high levels of stink bugs are present in many of the fields he scouts. We have also heard reports of high levels of stink bugs north of the lakes. Pyrethroids remain the most economical and efficacious materials for control of stink bugs. They will tank mix well with most fungicides. Be particularly careful when selecting a pyrethroid insecticide because many of the generic pyrethroids labeled for use in cotton are not labeled for use in soybean. CHECK THE LABEL to be sure you can legally use the product you have chosen on soybean.
The multiple new finds in South Carolina and Georgia and the new find in Louisiana aren’t necessarily a threat to more northern soybean fields. "I keep waiting for northward movement, but it has yet to happen," says Hershman. "Anyway, we (Kentucky growers) are beyond the point were soybean rust could damage our soybean crop. If it gets to Kentucky, we will have some great educational opportunities."
Amy Fahnestock, Sep 11 2006, 20:09More Georgia Counties Hit By Asian Soybean RustGeorgia officials report four new confirmations of Asian soybean rust — in four separate counties — during the past two days (Sept. 7 and 8). Only the newest finding was in a soybean sentinel plot, while the other three were in kudzu.
According to the state commentary on USDA’s Pest Information Platform for Extension and Education (PIPE) Web site, today’s (Sept. 8) confirmation was made at a University of Georgia research station in Midville. Midville is located in Burke County, an eastern county that borders South Carolina. "Rust was confirmed with a dissecting microscope on a soybean sample collected from our soybean sentinel plot in Midville," reports Layla Sconyers, University of Georgia plant pathologist. "One leaflet of 50 collected from Group IV soybeans was infected with rust (fewer than 20 pustules on the leaflet). This is the first rust find in that county this year."
On Sept. 7, the university officials reported findings of Asian soybean rust in kudzu samples collected Sept. 5 in Seminole, Grady, and Thomas counties. All are located near each other in southwest Georgia, bordering Florida.
This is not the first soybean rust detected in Grady and Thomas counties this year. Found during the winter months, officials believe the Asian soybean rust were destroyed at the time. "These rust infections found this week seem to be ’new’ infections — possibly spores were brought in with the recent and frequent rain showers we"ve been having," says Sconyers.
The soybean rust finding in Seminole County is the first at that particular site since 2004. "This is also believed to be a ’new’ infection, with spores perhaps being brought in with the recent rain events," reports Sconyers. "Rust was detected on all three smaples with a dissection microscope on two or fewer leaves per sample."
According to the PIPE national commentary, another soybean rust finding was noted Sept. 7 in Liberty County in Texas. The commentary states that "this detection is in a commercial field about 5 miles north of an earlier infected field."
On the same day, South Carolina officials reported confirmation of Asian soybean rust in a sentinel plot in Florence County, which is located in the eastern part of the state.
For more information, visit the PIPE Web site at hrrp://www.sbrusa.net.
Amy Fahnestock, Sep 08 2006, 14:30Another Georgia Sentinel Plot Falls Prey To Asian Soybean RustAsian soybean rust’s newest appearance is in a sentinel plot located in Colquitt County, GA, the seventh county in the state to have a confirmed sighting of the disease. While the confirmation was announced on USDA’s Pest Information Platform for Extension and Education (PIPE) Web site today (Sept. 5), it was actually detected on Aug. 28, according to Layla Sconyers, University of Georgia plant pathologist.
"Rust was detected with a dissection microscope on two leaflets with fewer than 10 pustules per leaflet on Group VII soybeans," reports Sconyers on the PIPE Web site. "This was a university soybean sentinel plot.
"With the recent rains and the detection of rust in South Carolina, it is extremely important that everyone continues to scout their soybeans for possible rust and be prepared to spray if you have not done so already."
To access the PIPE Web site, visit hrrp://www.sbrusa.net.
Amy Fahnestock, Sep 05 2006, 19:53Fungicide Spray Timing ReminderRetailers and their grower-customers should keep in mind that just because Asian soybean rust is found in an area, that doesn’t mean everyone should hop on a spray rig and start using approved fungicides.
"Yield losses due to rust do not increase after the R-6 (reproductive) growth stage," says John Mueller, Clemson University Extension soybean pathologist. Two sentinel plots in South Carolina were found to have Asian soybean rust in the past 10 days. Located in adjacent counties, the first plot in Calhoun County contained Maturity Group 5 (MG5) soybeans at growth stage R-5 (Aug. 21), while rust was confirmed on MG4 and MG5 fields in Orangeburg County on Aug. 31.
" The MG 4 plants are in the R-7 growth stage and the MG 5 plants are in the R-6 growth stage," Mueller says. "Yield losses due to rust do not increase after R-6. Also, it is illegal to apply fungicides after R-6 begins due to the required pre-harvest spray interval. Therefore these particular plots should not be sprayed.
"Our current weather is very favorable for the spread and development of rust and other fungal diseases of soybean," he adds. "The high relative humidity we have endured the past week coupled with rain from the hurricane today and tomorrow along with the afternoon thunderstorms projected for next week will help rust spread within and between fields.
"The two rust finds are almost in the center of our soybean growing region," says Mueller. "Although these are not extensive finds, they indicate that rust is present in South Carolina and could be in other fields throughout the state. Therefore it is appropriate to begin spraying for rust in any field in South Carolina where the yield potential is relatively high and the plants are at or past R-3/R-4 but not within 10 to 14 days of R-6. A strobilurin should be included in the spray to increase control of diseases other than rust. A combination of a strobilurin and a triazole could also be used."
Source: Soybean Rust Announcement e-mail from Don Hershman, Southern Region coordinator for the North Central Soybean Research Project and University of Kentucky Extension plant pathologist.
Amy Fahnestock, Sep 01 2006, 14:35Second Rust Finding In South Carolina ReportedAsian soybean rust has been confirmed in a second soybean sentinel plot in South Carolina, this time in Orangeburg County. The first confirmation was just 10 days earlier in Maturity Group (MG) 5 soybeans at growth stage R5 in neighboring Calhoun County. Orangeburg County is the adjacent county to the southwest.
John Mueller, Clemson University Extension plant pathologist, filed this report on USDA’s Pest Information Platform for Extension and Education (PIPE) Web site today (Aug. 31): " Rust was identified on leaves collected Aug. 28 from MG 4 and MG 5 sentinel plots in Orangeburg County. Initially six of 50 leaves from the two plots were infested. Four of the leaves had only one to five lesions with multiple pustules. Two of the leaves had 15-plus lesions with multiple pustules. Then 320 more leaves were collected on Aug. 30. Approximately 10% of these leaves were infected and 20% of the infected leaves had 10-plus lesions with multiple pustules. "
Mueller notes that there has been no rust observations on kudzu in the state this year.
He offers these cautions to growers: "The high relative humidity the past week along with the rain from the hurricane this week and the low temperatures and thunderstorms forecast for next week should be very favorable for the development of rust and other soybean diseases.
"Rust is probably present in South Carolina in more than just these two locations," adds Mueller. "Scouting of individual fields may be warranted. Some important points to remember in making spray decisions are:
- "Soybeans that have not flowered do not need to be sprayed."
- "Soybeans that are at or past R6 should not be sprayed."
- "A strobilurin or fungicide combination containing a strobilurin should be sprayed if you want to control diseases in addition to rust."
Mueller goes on to say: "The incidence of rust in South Carolina is still relatively low, but conditions are favorable for rust to spread within and between fields. If you are going to spray a fungicide in the next week, you need to include a strobilurin in the spray to optimize control of the most diseases possible. These sprays should be especially effective in high yield potential soybeans with a full canopy that are R3 to mid-R5 in growth stage."
The growth stage of a field will determine if spraying a fungicide is warranted. "Most of the April-planted Group 3, 4, and 5 soybeans are at or past R-7," Mueller says. "Most of the May-planted Group 6,7, and 8 soybeans are between R4 and R5. Only a few fields planted in June have not yet flowered. All of the fields at R6 or later are past the stage at which they can be damaged by rust or be sprayed with fungicides."
Don Hershman, University of Kentucky plant pathologist, sums up the national status in his PIPE report posted today (Aug. 31):
"Kentucky’s southern states — Oklahoma, Arkansas, Tennessee, Kentucky, North Carolina, and Virginia — continue to be clear of soybean rust. Rust can presently be found on soybean in South Carolina, and on kudzu AND soybean in Alabama, Florida, Georgia, Louisiana, Mississippi, and Texas. Presently, the greatest soybean rust activity is occuring in the states of Florida and Louisiana."
To access the PIPE Web site, visit hrrp://www.sbrusa.net.
Sources: The USDA Pest Information Platform for Extension and Education (PIPE) Web site and USDA’s National Soybean Rust Alert e-mail.
Amy Fahnestock, Aug 31 2006, 20:35More Rust In TexasA high incidence of Asian soybean rust was found on Aug. 25 in a commercial soybean field in Texas, very close to the Dayton kudzu patch in Liberty County (where rust has been found twice, most recently on Aug. 20). According to Tom Isakeit, Texas A&M University Extension plant pathologist, the latest find was a Group 5 soybean planted in April.
"The field is about 7 miles to the east of the Dayton kudzu," Isakeit says. "It is mature and will be harvested shortly. There are several other
commercial fields within 1 to 7 miles of this field that are at R2 to R5. There is no evidence of rust in these fields, so far, based on visual observations and leaf samples incubated 48 hours."
In South Carolina, no news is good news. Since the confirmation of soybean rust in Calhoun County on Aug. 21, officials have pulled and checked more samples in the same and adjacent fields of soybeans and kudzu patches, plus sentinel plots in the state. According to John Mueller, Clemson University Extension plant pathologist, no rust was found in these samples.
"Therefore, it appears we have only a very small trace amount of rust in the state," Mueller says. "Our find Monday (Aug. 21) was literally a needle in a haystack. The appropriate approach right now is to be wary, but basically not be concerned with rust until we make another find.
"Our recent rains (as of Aug. 25) have greatly improved our soybean crop in many areas," he continues. "In these areas where we now have soybeans in the R3/R4 growth stage, with high yield potentials and full canopies, I would strongly consider a fungicide spray program to control the diseases other than rust. Triazoles are not effective against these diseases. Therefore fungicides containing a strobilurin are the appropriate choice. Fungicides that are a combination of a strobilurin and a triazole will give some control of the ’other’ diseases since they contain a strobilurin."
Amy Fahnestock, Aug 29 2006, 15:39First Rust Confirmed In South CarolinaThe national Soybean Rust Alert system has been quite busy yesterday and today (Aug. 20-21), including the first confirmation of soybean rust in a soybean sentinel plot in South Carolina. This is the furthest north for rust confirmation in 2006. New findings of rust also were confirmed in Texas and Alabama kudzu.
John Mueller, Clemson University Extension plant pathologist, e-mailed this report:
"Asian soybean rust was identified in samples collected last Thursday (Aug. 17) in Calhoun County from a field of Maturity Group (MG) 5 soybeans located near the intersection of State Road 22 and Interstate 26.
"This is the first identification of rust in South Carolina during the 2006 growing season.
"The plants were in a sentinel plot and were at growth stage R5 (full-size pods containing developing beans). Out of the 25 leaves examined only one leaf exhibited rust. On that leaf was a lesion less than one-quarter inch in diameter which contained three very young pustules that had just begun sporulating. Immediately adjacent to this sentinel plot of MG 5 soybeans was a sentinel plot of MG 4 soybeans. No rust was detected on the 25 leaves examined from that plot. The MG 5 plot exhibited very lush growth, 40-plus inches tall in 38-inch rows.
"To keep this find in perspective, you should be aware that last week I examined almost 1,400 leaves from 43 soybean fields or sentinel plots in South Carolina. One leaf exhibited the smallest detectable level of rust (one lesion or clump of pustules). Also remember that the closest field in Georgia with soybean rust is near Tifton.
"To determine the real extent of the infestation tomorrow (Tuesday, Aug. 22), Charles Davis and I will be collecting extensive samples from the monitoring plots, neighboring kudzu, and soybean fields throughout Calhoun County. We should have these results by late Thursday. We will tell you immediately if rust appears prevalent in the area.
"In the meantime, we are predicted to have slightly cooler temperatures and a fairly good chance of thunderstorms at least from now until Friday, Aug. 25. This weather could be conducive to the development of rust and other pod, stem, and leaf diseases especially within a field."
Mueller recommends that producers do not need to spray soybeans that have not flowered and soybeans at late R5 or that are at or past R6. "To control diseases in addition to rust you must use a strobilurin or a combination product containing a strobilurin," he says.
"At this time the levels of rust in South Carolina appear to be extremely low. However, environmental conditions are favorable for rust and other diseases to develop. An application of a strobilurin to provide protection against rust and to help control other diseases is a good option for the next week. This is especially true for soybeans with a high yield potential that are between growth stages R3 and R5. At this time these soybeans show the highest potential for return from a fungicide application.
"We will update you on the incidence and severity of rust in South Carolina later this week," adds Mueller.
"This find is noteworthy in that this location in South Carolina is about 200 miles northeast of the closest find in Georgia," says Don Hershman, southern region coordinator for the North Central Soybean Research Project and University of Kentucky Extension plant pathologist. "This means that there is either undiscovered soybean rust somewhere in between the two locations, or the disease has skipped a considerable distance. We will know more later as both South Carolina and Georgia officials take a closer look."
Kudzu Findings Also Reported In Texas And Alabama. Tom Isakeit, Texas A&M University Extension plant pathologist, filed this report on Aug. 20:
"Yesterday, I did a soybean/kudzu circle tour through east Texas.
"The infamous kudzu patch near Dayton (in Liberty County) has rust again. The incidence is about 90% of leaves in a small area that I examined. There are about five to 200 pustules per leaflet, in very small lesions. Many of the pustules were not well developed, but the amount of sporulation improved with overnight incubation.
"It was the last stop of the day and I was rained out before I could check out more of the patch. I was last out here in mid-July and didn’t see anything. The county agent has been checking it more frequently since then.
"There were periodic showers in the area over the past two weeks.
"I checked out two soybean fields in the county and there was no evidence of rust. I also checked out kudzu in Livingston (Polk County) to the north of Dayton and in Newton County (borders Louisiana), as well as the sentinel soybeans in Beaumont. There was no evidence of rust in these locations.
"We will be monitoring commercial soybeans in Liberty County over the next week. We will also scrutinize more of the kudzu patch."
According to the USDA Pest Information Platform for Extension and Education (PIPE) Web site, Asian soybean rust was detected and confirmed on kudzu in the city of Montgomery. The rust was subsequently destroyed on Aug. 21. The PIPE Web site can be visited at http://www.sbrusa.net.
Ed Sikora, Auburn University Extension plant pathologist, filed this report on the PIPE Web site:
"The disease had previously been detected on five kudzu patches in the downtown area (of Montgomery) where it had successfully overwinters. These patches have been monitored on a bi-weekly basis since they were first discovered in January. The disease has not been detected at these kudzu sites since early June. Central Alabama has experienced a severe drought for most of the growing season which likely had a direct impract on the pathogen’s ability to survive."
Sikora does recommend that growers in the Baldwin County apply a triazole or triazole/strobilurin premix or tank mix, and Escambia County growers consider applying a triazole/strobiluring combination if their crop is between bloom and pod fill and if they have been experiencing frequent rains in their area. These recommendations are in response to recent Asian soybean rust confirmations in area soybean sentinel plots.
Overall Update. Currently rust has been found in soybeans in 15 different counties in Alabama, Florida, Georgia, Louisiana, Mississippi, and now South Carolina. Including reports on kudzu, a total of 35 counties have been confirmed for rust this year. This includes 13 in Florida, seven in Louisiana, six in Georgia, five in Alabama, two in Texas, and one each in Mississippi and South Carolina.
Sources: The USDA Pest Information Plantform for Extension and Education (PIPE) Web site and e-mails from Don Hershman, University of Kentucky Extension plant pathologist.
Amy Fahnestock, Aug 21 2006, 21:19Rust Continues To Spread In Spot AreasReports from Alabama and Louisiana indicate that rust continues to surface.
Ed Sikora, Auburn University Extension plant pathologist, gives this rundown on the situation in Alabama:
"On Aug. 10, soybean rust was detected in a late-planted soybean sentinel plot in Baldwin County near the town of Fairhope. The disease had been detected in an earlier planted soybean sentinel plot at the same location on June 27. That plot was destroyed shortly after discovery of the disease.
"On Aug. 10, the disease was observed on both a maturity group IV and a group VI variety planted side by side. We detected the disease on three groups of plants in the maturity group VI plot. Rust pustules were observed on multiple leaves situated very low in the canopy in three areas within this plot. Overall, disease incidence and severity was relatively low. Growth stage of the maturity group VI variety was R5. Symptoms of soybean rust were also observed on a few leaves on one plant in the group IV plot which was at the R6 growth stage.
"This area of Alabama has been receiving frequent afternoon showers for the last 7-10 days.
"Last week, a survey was conducted in the 14 southern counties of Alabama that border Mississippi in the southwest, Florida in the south, and Georgia in the southeast. No rust was detected in the 40 kudzu patches and/or commercial soybean fields scouted during that two-day trip."
Sikora recommends that the growers in the Baldwin County area spray a fungicide application of a triazole or triazole/strobilurin premix or tank mix. "Soybean growers in Escambia County should also consider an application of a combination of a triazole and a strobilurin fungicide if their crop is between bloom and pod fill and if they have been experiencing frequent rains in their area," he says. "It is not considered economical to apply fungicides for soybean rust prior to bloom or after pod fill. Be aware of soybean rust alerts for your area to determine if rust is a threat."
He reminds Alabama producers to call the Auburn University Soybean Rust Hotline, 800-446-0388, for weekly updates.
In addition to the finding in Natchitoches Parish reported on this Web site yesterday, two other Louisiana parishes have had confirmed reports of Asian soybean rust — Avoyelles and Tensas, both confirmed on Aug. 15. Again, these reports were the first for their respective parishes. This brings the total of Louisiana parishes in which Asian soybean rust has been confirmed in either soybeans or kudzu to six.
According to the state commentary on USDA’s Pest Information Platform for Extension and Education (PIPE) Web site, Louisiana soybean growers in the affected areas should monitor crops very carefully.
"The recommendation is for soybeans in the R1 through R5 growth stages and have a good yield potential be treated with a rust fungicide," the commentary states. "The fungicides for rust control have a triazole alone or in combination with a strobilurin. These products are listed in the 2006 Plant Disease management Guide and are on the LSU AgCenter Rust Web site, www.lsuagcenter.com/soybeanrust."
Source: The PIPE Web site, www.sbrusa.net and an e-mail from Ed Sikora, Auburn University.
Amy Fahnestock, Aug 16 2006, 14:26Rust Found Farther North In LouisianaAsian soybean rust was found in a sentinel plot of soybeans in Natchitoches Parish, LA, on Aug. 11 and confirmed on Aug. 14, according to a report filed on USDA’s Pest Information Platform for Extension and Education (PIPE), http://www.sbrusa.net. The soybeans are Group Vs and are at R5 growth stage. This is the northernmost confirmation of soybean rust on soybeans in the state.
According to the Louisiana state update, filed Aug. 14, "The recommendation is for soybeans in the R1 through R5 growth stages and have a good yield potential be treated with a rust fungicide. The fungicides for rust control have a triazole alone or in combination with a strobilurin. These products are listed in the 2006 Plant Disease Management Guide and are on the Louisiana State University AgCenter Rust Web site, http://www.lsuagcenter.com/soybeanrust."
The report cautions area retailers and their grower-customers that "it is especially important at this time to monitor your crop very carefully and be alert for reports of disease outbreaks in the area." Retailers and growers can monitor the AgCenter’s Web site, their local county agent, or the Asian Soybean Rust Hotline at 800-516-0865.
Source: The USDA Pest Information Platform for Extension and Education (PIPE), www.sbrusa.net
Amy Fahnestock, Aug 21 2006, 21:15Two New Georgia Rust FindingsSoybean rust was confirmed this week on kudzu in Attapulgus, GA, which is located in Decatur County. This same kudzu site was infected with rust in 2005, however, no disease was found in this site during the winter months. Decatur County is located in south central Georgia along the Florida/Georgia border and about 15 miles north of Quincy, FL, where rust has already been confirmed.
Rust was also found this week on group IV soybeans growing in a sentinel plot at the University of Georgia Lang Research Farm in Tifton, GA. One leaflet of 50 was infected (lower canopy, low severity) with soybean rust.
This is the second rust find in Tift County, GA, so this find was no
surprise. Tift County is located in south central Georgia. Rust was confirmed with a dissection microscope. It is possible that the recent rain events could have moved spores from north Florida into Georgia. Scouting continues across the state.
Most of our soybean sentinel plots (MG-IV and MG-VI) are now at the R6+
growth stage as of Aug. 11. Commercial soybeans in our state range from
about R3 to R7 stages.
Source: Dr. Layla E. Sconyers, post-doctoral research associate, University of Georgia Coast Plan Experiment Station
Amy Fahnestock, Aug 15 2006, 18:10Rust Found For Third Time In GeorgiaAsian soybean rust was confirmed today (Aug. 7) in group IV soybeans in Tift County, which is located in southcentral Georgia. The soybean field is located on an industry research farm in the community of Chula.
According to Layla Sconyers, University of Georgia plant pathologist, "This is the first rust find in that county. A small leaf sample (less than 10 leaflets) was submitted to the University of Georgia diagnostic clinic, and rust was confirmed with a dissection microscope.
"It is possible that the recent rain events could have moved spores from north Florida," Sconyers says.
Most of the state’s soybean sentinel plots (MG-IV and MG-VI) are — as of Aug. 4 — at the R7+ growth stage, adds Sconyers. "Commercial soybeans in our state range from about R1 to R7 stages."
This confirmation is the sixth county overall in Georgia and the third In the state’s soybeans in 2006. It was found in soybean research plots on July 10 in Decatur County and June 27 in Brooks County. The only state with more counties reporting soybean rust confirmations — in either soybeans or kudzu — is Florida with 13 counties so far this year.
Amy Fahnestock, Aug 07 2006, 18:25Rust Now Found In Mississippi Mississippi’s first report of Asian soybean rust for the 2006 growing season includes one confirmation in soybeans and another in kudzu — both in Jefferson County, which is located in the southwest corner of the state. A total of eight counties in five states (Alabama, Florida, Georgia, Louisiana, and now Mississippi) have confirmed Asian soybean rust in soybeans this season. A total of 28 counties have confirmed soybean rust in either soybeans or kudzu, including five in Alabama, 13 in Florida, five in Georgia, three in Louisiana, this newest one in Mississippi, and one in Texas.
Alan Blaine, Mississippi State University Extension plant pathologist, reports on USDA’s Pest Information Platform for Extension and Education (PIPE) Web site, http://www.sbrusa.net: "Rust was heavy on kudzu in an area about 30 feet in diameter. However, rust was difficult to find in the soybeans. Producers in the southwest portion of the state that have soybeans that are in reproductive growth stage R5.5 or a younger reproductive stage need to consider application of a fungicide, particularly a triazole or a mix (triazole+strobilurin).
"Soybean growers in our major soybean growing areas in north Mississippi and the Delta have nothing to be concerned about at this time. It’s been hot and extremely dry in those areas, unfavorable for rust development. Scouting will continue, and these management suggestions will be modified based on the scouting results and weather conditions."
According to the PIPE National Soybean Rust Commentary, updated on Aug. 1: "Dry to very dry conditions have prevailed in the spore source regions and movement to new areas has been slow."
On the same Web site, the Asian soybean rust public forecast notes the risk areas for specific dates. The comments for Aug. 3-4 (made Aug. 2) include: "The spread of soybean rust is possible in the central regions of Alabama and Georgia due to cloudier conditions, scattered rain, and southerly wind patterns. Southern and eastern Texas as well as the extreme western Louisiana should note a decrease in the risk due to the dry and sunny weather."
And the Aug. 5-7 risk area forecast commentary says: "Expect warnings along the Gulf Coast and down to the Florida peninsula. High risk should also affect regions north of the Gulf Coast, in particular areas in the lower Tennessee Valley to the Carolinas due to moderate to strong winds from the southeast, prolonged showers, and thunderstorms and a lack of sunshine."
"Soybean rust was found in Mississippi twice last season, but in both instances the finds were in soybean sentinel plots which were completely destroyed immediately following rust detection,"says Don Hershman, University of Kentucky Extension plant pathologist. "The current soybean find is in a commercial field, and I doubt very much if eradication is an option. Similarly, eradicating heavily infected kudzu is considered by most scientists to be an exercise in futility. Thus, the current infections are likely to stand and soybean rust will increase, at least in the kudzu, and perhaps in the soybean field unless the grower is able to move quickly and apply a fungicide that brings the situation under control. I also think it is only common sense that if soybean rust was found in two locations in Jefferson County, MS, it is almost certainly in other fields and kudzu patches in that county (and perhaps neighboring counties).
"These finds, as well as the earlier finds in Louisiana, are noteworthy because of the frequency with which weather systems move into the upper Midsouth after passing through Louisiana and Mississippi. Fortunately, dry weather in the northern and Delta areas of Mississippi (and much of Arkansas) greatly limits the potential for soybean rust to develop in the upper Midsouth (i.e. Tennessee and Kentucky).
"The short-term prognosis for Kentucky soybean producers has not changed: the soybean rust risk continues to be low," Hershman adds. "However, the long-term prognosis suggests that we may see soybean rust in Kentucky earlier and to a greater extent than we did last season (which was minimal, to say the least). The weather both here and in source areas for rust spores will determine if, when, and to what extent soybean rust moves during the remainder of the season in the U.S. However, I continue to believe that the soybean rust risk to Kentucky’s full-season soybean crop is minimal due to the advanced crop stage and the amount of time required to develop full-blown soybean rust in a field once soybean rust spores arrive (assuming conditions favor soybean rust development). Similarly, if I were a betting man (which I am not), I will guess that most, if not all, of our doublecrop soybean acres will also escape damage this season. Time will tell."
Ag retailers and growers should always consult the Forecast Outlook and Disease Management commentaries supplied by their own state soybean specialist at the USDA Web site.
Sources for this article: USDA’s Pest Information Platform for Extension and Education; and Don Hershman, Extension plant pathologist, University of Kentucky.
Amy Fahnestock, Aug 03 2006, 16:40Georgia Weather Favoring Disease GrowthHere’s an update for the state of Georgia from state Extension plant pathologists Bob Kemerait, Layla Sconyers, and Phil Jost:
"Agents in counties where peanuts and soybeans are produced should recognize that disease management in both crops could become critical in the next weeks as the chance for rain increases and warm temperatures persist.
"Although Asian soybean rust has been confirmed on kudzu in Miller and Brooks counties and on soybean research plots in Brooks and Decatur counties, it has really not spread much at all this year, likely due to hot and dry weather. NOTE: Frequent storms and flowering-reproductive growth stages of our commercial crop could easily rekindle this disease across the state.
"Soybean producers in the southwest corner of Georgia should be on high alert for soybean rust. The most conservative approach to managing this disease would be to make a fungicide application during the blooming growth stage and follow with a second 14 to 28 days later if conditions favor disease spread.
"Many growers may also choose to wait to apply the fungicide application UNTIL we are able to document rust spreading in our sentinel plots and research plots. For example, though rust was found on soybean plants in Attapulgus, Decatur County (1 leaf of 100) on July 3, we have NOT found the rust again on July 10, July 17 or July 24. We have also NOT found rust in sentinel plots in Moultrie (SunBelt Expo) or elsewhere.
"Many soybeans will be approaching the R3-pod formation growth stage soon. Growers may wish to mix a fungicide, for example chlorothalonil or fungicides, with dimilin or boron applications to increase disease control (e.g. frogeye leaf spot) as well."
And here’s a quick note from Don Hershman, University of Kentucky Extension plant pathologist, regarding the Georgia situation: "The soybean rust risk continues to be very low. The soupy weather is perfect for soybean rust development and the crop is highly vulnerable, but we are apparently missing the pathogen leg of the disease triangle. No pathogen, no disease. I pray we will continue to be blessed in this way."
Amy Fahnestock, Jul 31 2006, 17:43Another Rust Confirmation In Florida SoybeansA new positive identification of Asian soybean rust was confirmed in Florida on July 27. Although it was the first incidence in Jefferson County for this growing season, soybean rust had been confirmed in the county last year.
This comes just two days after soybean rust was confirmed in three Gadsden County sentinel plots in north central Florida. Thus far this season, there have been soybean rust confirmations in 27 counties in four states (including 13 in Florida). Overall, rust has been found on soybeans in seven different counties in the four affected states; the rest of the confirmations have been in kudzu.
Here is a first-hand account from Jim Marois, University of Florida Extension plant pathologist:
"A sentinel plot in Jefferson County was positive from samples taken July 27. Two leaves from MG-VII were infected with several lesions and one leaf from a MG-V sample had one pustule. This is the first finding of rust in the county for 2006 — it was positive in 2005. Jefferson County is east of Leon County (Tallahassee). Also on July 27, a new kudzu site was found positive in Alachua County (Gainesville). We also found positive infections in the sentinel plots in Gadsden County the week before last. Rains seem to be moving the pathogen to new locations."
Most commercial soybeans in Florida are planted and at late vegetative stages or early reproductive stages, according to the Florida state commentary on the Pest Information Platform for Extension and Education (PIPE) Web site, http://www.sbrusa.net, the official USDA Asian soybean rust Web site.
The PIPE update also notes that the Alachua County’s infected kudzu is "about 12 miles north of an active infection site on kudzu in Marion County." The infected soybean sentinel plots in Gadsden County "are located within 3 miles of a known positive kudzu site. All positive plots are actively sporulating. It appears that recent rains have begun to spread the disease. No other sentinel plots in the panhandle are known to be positive at this time."
The update continues: "We have returned to a more normal rainfall pattern, with most days having rain somewhere in the region, although often it is very local. Still, in the panhandle we are about 50% below normal rainfall for the year. Humidity is high and dew is present, so infections and sporulation is ongoing in infected plots.
"As most counties are still negative, risk of rust to soybean growers in Florida is still minimal at this time. However, growers should re-evaluate the situation frequently.
"A Florida rust hotline has been established. A nationwide toll-free number (866-361-9942) can be used to access it."
Amy Fahnestock, Jul 31 2006, 15:58Soybean Rust Not A Factor In Kentucky FieldsBy Laura Skillman, University of Kentucky
PRINCETON, KY – Another year of waiting and watching for soybean rust is about over for many soybean producers in the state as their beans are maturing and the disease has yet to make an appearance. Late-planted soybeans could still be impacted, but for now there is little cause for concern.
No soybean rust has been confirmed in any commercial soybean fields in the U.S. In Kentucky, 22 sites in 19 counties currently are being monitored for soybean rust on either kudzu or soybean as part of the national soybean rust sentinel plot network.
"The risk of soybean rust in Kentucky is very low at this time; no control measures are warranted," says Don Hershman, plant pathologist with the University of Kentucky College of Agriculture. "Full-season soybeans are just about out of the woods for this year. Late-planted crops will be vulnerable for a time yet and could still be severely damaged by soybean rust if the disease moves into Kentucky during the next month."
Hershman notes, however, that his observations on the disease are contingent on it "acting" like it did last year.
"By way of a disclaimer, it is possible that soybean rust could blow up and develop into an epidemic much faster than it did last year," he says. "If that were the case, even full-season beans would be at risk. But the way things are looking now, that doomsday scenario is not very likely to happen this year. Who knows how soybean rust will develop in the future, so it would not be prudent to think that the low soybean rust in 2005 and now, apparently, in 2006 is the way it will always be.
"My point is that it would be a great error to let soybean rust pass off your ’radar screen’ even if it never makes it to Kentucky this season," Hershman says. "The odds are very high that we will have to deal with soybean rust in a significant way at some point in the future. We just don’t know when that will happen."
Asian soybean rust was first discovered in the U.S. in November 2004. Since that discovery, crop and disease specialists across the soybean growing region have been working to understand how the disease develops and its impact on the crop. They have also been educating producers, field scouts, agricultural suppliers, and others about this new threat.
For the past two years, the disease as been slow to move from its overwintering locations in the far south into soybean producing regions. Most of the locations where the disease has been discovered have been on kudzu and in sentinel plots.
Soybean rust has yet to be discovered on any of Kentucky’s soybean crop. It was found in November 2005 on a kudzu leaf in Caldwell County by Hershman. But Kentucky’s cold winter temperatures make overwintering by the disease unlikely.
The Kentucky hotline, 888-321-6771, provides up-to-date information on Asian soybean rust.
(For more information on the national Asian soybean rust situation, click on "From The Editors".)
Amy Fahnestock, Jul 27 2006, 18:16Tracking Rust Progress In KudzuLast week, Dr. Bob Kemerait, Extension plant pathologist at the University of Georgia, examined kudzu at an abandoned home in downtown Colquitt, GA. Colquitt, in Miller County, is located in the southwest corner of the state (see "First 2006 Rust Found In Florida Beans," in an entry dated June 16).
He found rust on kudzu that appeared to have survived winter and was living on plant tissue close to the home, which would have been protected from winter conditions.
Dr. Kemerait collected 10 leaves from the focal point (where the rust had survived), 21 leaves were collected from about five "paces" from the focal point, 19 leaves were collected from about 10 paces from the focal point, 28 leaves were collected from about 15 paces from the focal point, and 25 leaves were collected at 20 paces.
After examining these leaves with a dissection microscope, Dr. Layla Sconyers found rust to be on ALL leaves (10) collected from the focal point, with low to moderate severity. At five "paces", eight of the 21 leaves collected were infected with rust, with low severity. Some of the leaves had less than five rust pustules.
At 10, 15, and 20 paces, none of the leaves had rust. This is useful information for us. We now know that rust did survive
the winter on kudzu in Miller County, and that the spread from the focal point is not extensive at this point -- it seems
to be spreading slowly in this particular site. We will continue to ’map’ the progress of disease at this particular site to get a better idea of the time involved in disease spread in kudzu. We will keep everyone posted of further developments.
Source: Dr. Layla Sconyers, post-doctoral research associate at the University of Georgia’s Coast Plain Experiment Station
Amy Fahnestock, Jun 20 2006, 13:12New Web Site Features International ProjectBy Dr. Don Hershman, Extension plant pathologist, University of Kentucky
Dr. Saratha Kumudini (a plant physiologist in the University of Kentucky Department of Plant and Soil Sciences) and co-workers have developed a Web site for an international, multi-institutional Asian soybean rust yield loss project. Funding for the project comes from the Risk Management Agency, USDA, and the Southern Soybean Research Program (SSRP).
The project’s home page is http://www.uky.edu/Ag/Agronomy/Department/sbr There you can read the project’s mission, get updates, find out what is being done and by who, and read about the project’s goals.
Rather than to go into detail here, I suggest you to go the Web site and read about it. In my opinion, the project is quite unique and should generate a product with great value to the soybean industry upon completion.
The second link, www.uky.edu is from the Resources section of the project home page. I am bringing this to your attention because it includes two very unique Brazilian resources. The first is a rather large powerpoint show developed by EMBRAPA for their agricultural community, but in an English version.
The second document is a concise soybean rust flyer that we have translated into English. In some respects, the flyer is a miniature version of the powerpoint. The main value of the flyer is that it contains more up-to-date fungicide efficacy information. The fungicide efficacy table is based on numerous Brazilian research trials conducted during 2003-05 by scientists in the Brazilian Anti-Rust Consortium. The Consortium is under the leadership of EMBRAPA’s Dr. Claudia Godoy.
Note, both Brazilian resources are being provided as supplemental information only. We have included the following disclaimer at the beginning of each document:
The following translated document originates from Brazil, is based on Brazilian data and experience, and was developed by EMBRAPA for Brazilian farmers. Aspects of soybean rust development and fungicide efficacy comparisons may not be the same under U.S. and Brazilian conditions. Similarly, certain control measures suggested by Brazilian officials reflect the unique soybean rust situation in Brazil, as well as year-round soybean production in certain parts of that country. Therefore, do not use this information for making fungicide purchasing or soybean rust control decisions in the U.S. Instead, use control measures developed by your state’s Land Grant University scientists. Be advised that fungicide product names for the same active ingredient and manufacturer are typically different for Brazil and the U.S.; however, the common names for the active ingredient (such as tebuconazole or propiconazole or azoxystrobin) are the same in both countries.
For more information or clarification about the translated document, contact Dr. Hershman at dhershma@uky.edu.
Editor’s note: According to Ana Reho, managing editor of Productores de Hortalizas, a sister publication to CropLife magazine, EMBRAPA is the Brazilian Agricultural Research Corp. and fills a similar role as USDA in the U.S.
Amy Fahnestock, Jul 17 2006, 20:44First 2006 Rust Found In Florida BeansFlorida officials have reported soybean rust at a sentinel soybean site in Martin County. This is the first report on soybeans planted in 2006. Martin County is located in southeastern Florida near West Palm Beach.
Even with this find, Florida officials feel the overall spore production in the state is still low. See the state commentary below for more details.
Scouting has intensified in soybean sentinel plots, especially in the South as soybeans reach maturity. Most of the soybean sentinel plots have been planted throughout the country, with plants in some early planted plots starting to reach matuity. Scouting continues on kudzu patches from Florida to as far north as Nebraska.
Soybean rust was found in kudzu on June 14 in Miller County, GA, in the southwest corner of the state. This site was previously found to have rust during the winter months. Rust has been confirmed in five counties in Alabama, 12 in Florida, four in Georgia, and one in Texas. Many of the Southern states were experiencing hotter and drier than normal conditions, reducing the likelihood of viable spore dispersal.
Spore trapping continues throughout the U.S. using both active and passive traps. Any positive spore trap information does not imply infection has taken place and plant samples are used exclusively for indicating positive rust occurrence as indicated on the soybean rust observation map.
Florida state commentary, dated June 16:
A soybean sentinel plot in south Florida (Martin County, near West Palm Beach) was confirmed positive by PCR (polymerase chain reaction). This plot was identified as being near a source of rust, so its early infection is not surprising. At this time no other sentinel plot in Florida is known to be positive, although several others are near known rust infestations.
On June 11-13, Tropical Storm Alberto moved through Florida. Although the western panhandle was not affected, Tallahassee received 4 inches of rain, with more rain and wind toward Jacksonville. The direction of the storm path was towards the northeast, so if any spores were carried from Florida and the Southeast they would likely have ended up in the Eastern seaboard. With this said, we feel the overall production of rust spores in Florida is still very low due to our previously dry conditions; the spore load would probably be greater with storms later in the season.
Following Alberto the soils are saturated and there is considerable fog and dew formation, providing further opportunity for rust to develop. If Alberto does have an impact on soybean rust, we expect it to be observed in the sentinel plots during the new few weeks. The Florida kudzu canopy is fully developed and flowering. All other soybean sentinel pltos are still negative and at R1-R3 maturity stages.
Source for both the national and Florida commentary: USDA’s Pest Information Platform for Extension and Education.
Amy Fahnestock, Jun 16 2006, 20:14Kentucky’s Soy Rust Hotline Offers New ServicePRINCETON, KY – The Soy Rust Hotline is available for the second year as a tool in the fight against soybean rust. Call 888-321-6771 to hear a daily report with the most current information on soybean rust in Kentucky. Dr. Don Hershman, Extension plant pathologist with the University of Kentucky, provides daily or as-needed updates, which include location of the disease, management steps that need to be taken, and points for possible prevention.
"The hotline proved to be a successful tool in keeping up with the location of rust last year," says Randy Mann, Kentucky Soybean Promotion Board (KSPB) chairman and soybean producer from Auburn. "This year we are moving a step forward and offering a new service that documents Dr. Hershman’s daily messages and makes them accessible as audio files, online in a database. The messages are archived on the KSPB Web site and can be heard beginning this month."
"The documentation of the messages being heard on the hotline may be vital in later development of the disease," continues Mann. "If the disease hits, farmers relying on crop insurance will be able to have hard documentation on what the experts were saying at the time critical production decisions were made. This documentation can support their production practices on whether they sprayed or did not spray fungicides for soybean rust management. Good records will be essential in the event a soybean rust related crop loss claim is filed.”"
Dialing 888-321-6771 can access the hotline. Daily messages can be heard at www.kysoy.org.
Source: The Kentucky Soybean Promotion Board
Amy Fahnestock, Jun 12 2006, 13:46Rust Reappears In Florida KudzuThe state of Asian soybean rust in Florida according to Jim Marois, professor of plant pathology for the University of Florida, as of June 9:
"We are having local showers, but overall the state is still very dry. Yesterday (June 8) we once again found soybean rust on kudzu in Gadsden County. This is the site in the Panhandle of Florida that was positive in January, then negative during February after freezing weather, positive again in March when it warmed up, then negative again in April and May when we got dry.
"What is interesting is that the severity was moderate -- a lot of leaves had several lesions. This may mean the rust, since we have had little rain, is getting its water for germination from
dew, which we have had overnight for several days. The Florida kudzu
canopy is fully developed and flowering has begun in several areas.
"All of the soybean sentinel plots are still negative with several plots
having the MGIII starting to bloom (R1-R2). All kudzu monitoring sites
and sentinel plots are being visited weekly."
Amy Fahnestock, Jun 09 2006, 18:26New Documentation Tools Available For Rust Prevention, ControlWASHINGTON: Agriculture Deputy Secretary Chuck Conner has announced the launch of the Risk Management Agency’s (RMA) Good Farming Practices Documentation Tool. This tool, available via the Internet or through a crop insurance agent, enables growers to quickly and accurately record actions taken to prevent and treat any outbreak of soybean rust.
"The likelihood of soybean rust migrating to new states remains and we are committed to helping producers to effectively manage this plant disease, " says Conner. "This new tool will assist producers in substantiating that good farming practices were followed. Early detection and treatment, along with good documentation, is critical for the determination of cause of loss should producers need to file an insurance claim related to soybean rust. "
The newly developed Good Farming Practices (GFP) Documentation Tool is available at http://www.sbrusa.net, the comprehensive one-stop shop for soybean producers to review all the available information on the prevention and control of Asian soybean rust.
The documentation tool is part of USDA’s Pest Information Platform for Extension and Education (PIPE). PIPE is an online, real-time observation and forecasting system that allows growers to access the latest information about which counties have confirmed the disease and/or insect pest outbreaks. State Extension specialists provide frequently updated commentaries discussing the immediate and future risks and control guidelines. Growers can sign up for e-mail notification when risks change for soybean rust in their states. PIPE tracks the spread of soybean rust as well as soybean aphids in soybeans and dry beans.
PIPE helps producers make timely, crop management decisions to reduce pesticide input costs, reduce environmental exposure to pesticides, and to increase the efficiency and efficacy of pesticide application.
Launched last month, the nationally coordinated PIPE network grew out of USDA’s Soybean Rust Information System. That system is estimated to have helped increase U.S. soybean growers’ profits by as much as $299 million in 2005, at a cost of less than $5 million, according to a study by the Economic Research Service.
Additional state-specific information will be provided as these options are made available to state specialists and as the soybean crop develops. USDA’s Cooperative State Research, Education and Extension Service, Risk Management Agency, and Animal and Plant Health Inspection Service are cooperating on the implementation of PIPE.
For more information on PIPE, the Good Farming Practices Documentation Tool or soybean rust, go to http://www.usda.gov/soybeanrust/.
Source: USDA News
Amy Fahnestock, Jun 06 2006, 13:13PCR Assay Proving Reliable For Early Soybean Rust DetectionST. PAUL, MN: A significant research step has been taken in the fight against Asian soybean rust.
A recent research article, "Early Detection of Asian Soybean Rust Using PCR," published in Plant Health Progress www.plantmanagementnetwork.org/php an online, peer-reviewed journal whose scope covers applied plant pathology, entomology, and nematology, demonstrated the reliability of the polymerase chain reaction (PCR) assay in detecting the presence of Asian soybean rust within six days of infection, before damaging spores can be generated.
"The entire soybean industry is going to benefit from this study," says James P. Stack, a plant pathology professor at Kansas State University and co-author of the article. "Without using PCR, you have to wait as many as nine days to see the spores. Then a diagnostic must be done before an applicator can be called in to apply a fungicide spray to the soybean field. During that time, the disease is still increasing, and its opportunity to spread increases too. Whatever you can do to shorten the time interval from detection to response, you are minimizing the impact."
The study was conducted in seven laboratories across the United States and involved 17 scientists from USDA and five U.S. land grant universities -- the University of Tennessee, Cornell University, Kansas State University, Michigan State University, and the University of Florida.
In a USDA containment facility, soybean plants were inoculated with Asian soybean rust spores. After infection, plant tissue was harvested seven times over 12 days. DNA was then extracted from the harvested tissue and tested for the presence of soybean rust using conventional and real-time PCR assays at each lab. Across these seven labs, soybean rust was consistently detected six days after inoculation.
The study demonstrated the PCR assay’s ability to repeatedly detect Asian soybean rust on soybean plants before the presence of readily visible symptoms.
"This should demonstrate to the user community that the soybean rust PCR assay is reliable and useful for early detection," says Douglas Luster, research leader at USDA’s Agricultural Research Service (ARS) Foreign Disease-Weed Science Research Unit in Maryland and co-author of the study.
Also of significance, the researchers demonstrated the reproducibility of results using different PCR platforms.
"The results came out on top of each other," says Reid Frederick, a researcher at the Maryland research unit and another co-author of the study. "It was rewarding to see that it is reproducible in different people’s hands."
"This is the first step in validating this assay," says Luster. "The next step is testing the assay with real-world samples from soybean field plots."
Source: Plant Management Network
Editor’s note: Plant Health Progress is a publication of the Plant Management Network, a cooperative resource for the applied plant and agricultural sciences. Designed to provide plant science practitioners fast electronic access to proven solutions, the Plant Management Network offers four science-based applied journals, four field trials publications, and an extensive searchable database comprised of thousands of Web-based resource pages from the network’s partner universities, companies, and associations. For more information, visit www.plantmanagementnetwork.org
Amy Fahnestock, Jun 06 2006, 12:13So Far, All’s Quiet On Midwestern Soybean Rust FrontOnly time and weather patterns will tell whether Asian soybean rust
moves into the Midwest this year and, so far, neither is talking, says Greg
Shaner, Purdue University plant pathologist.
As much as agricultural researchers learned about the fungal disease in 2005, they still can’t say if and when rust will infect the Corn Belt, Shaner says. He advises producers to keep a close eye on their fields and on weather reports this season. Growers also can stay up on rust’s whereabouts through Purdue.
"We’ve had so little experience with this disease in the United States that it’s really difficult to say what our risk for rust infection is in the Midwest," Shaner says.
"I think most people feel that here in the Corn Belt we’re not likely to see rust before soybeans flower in late July and August, and probably even later than that. Rust might not occur until the beans are beginning to fill the pods. In any case, we need to remain vigilant until the beans are pretty well developed. Then, if rust doesn’t appear until that stage, there probably wouldn’t be enough time for it to do much damage."
In 2005 soybean rust confined its crop-infecting activities to the southern United States. Despite a record hurricane year that seemed primed to push rust into the nation’s midsection, the disease never made its way above the Mason-Dixon Line.
Rust infection this year is following a similar pattern. To date, rust has been confirmed in Florida, Georgia, Alabama, and the southern tip of Texas. The infected area in Texas and two others in Alabama and Georgia were destroyed.
"Right now rust isn’t moving," Shaner says. "There have been no new rust findings since early March."
Soybean rust is a foliar disease caused by the fungus Phakopsora pachyrhizi. The fungus forms tan lesions on soybean leaves. Infected leaves die and fall off, severely limiting the soybean plant’s ability to produce seeds. In extreme cases, the disease can wipe out 80 percent of a soybean field’s yield potential.
Worrisome to researchers and farmers is how quickly and easily rust can spread. Rust pustules produce spores that start the infection process within days of landing on soybean leaves. One moderately infected soybean plant can produce about 6 million spores per day.
"The way this fungus gets from one place to another is by the wind carrying the spores," Shaner says. "We know from last year spores were carried into the Midwest and even into the northern Plains, but we didn’t see rust in those areas."
Spores that traveled into Indiana and neighboring states likely hitched rides on hurricane remnants, Shaner says. Researchers don’t know if those spores were viable when they arrived in the Midwest, leading some to wonder whether rust is a poor traveler.
"It is possible that even though the spores may be carried long distances, they don’t survive the flight," Shaner says. "If that’s the case, then maybe our risk is considerably less than we’d originally thought based on what we know about rust on cereal crops and corn."
Purdue and sister land-grant universities across the country are prepared in case rust heads north.
"As we did last year we will again have what we call sentinel plots," Shaner says. "These are small plots of soybean that are planted throughout the state. We’ll probably have about 23 of these sites (in Indiana)."
Purdue researchers had hoped to plant sentinel plots earlier than most soybeans, so that rust might infect those plots first, Shaner says. However, a wet spring has interfered with early planting at some locations, he says.
Sentinel plots are intended to act as an early warning system, Shaner says.
"Once the beans in those sentinel plots begin flowering, which will be late June, cooperators will monitor those plots once a week," he says. "They will collect 100 leaves and send those by overnight mail here to Purdue, where those leaves will be examined under a microscope for any evidence of rust."
Should rust be confirmed on sentinel plots, farmers will be notified through various media outlets. Indiana farmers will also be notified via Purdue information sources, including a toll-free rust hotline.
The hotline -- (866) 458-RUST (7878) -- will feature recorded rust updates from Shaner. The phone line will be activated about mid-June, or sooner if circumstances warrant.
Other Purdue soybean rust resources include:
Purdue Agriculture Soybean Rust Web site -- Contains Purdue-related soybean rust news and links, located at http://www.agriculture.purdue.edu/soybeanrust/.
Purdue Plant and Pest Diagnostic Laboratory Soybean Rust Web site -- Provides information on submitting soybean leaf samples to the laboratory, plant scouting, soybean rust host plants, fungicides, and more. The site is located at http://www.ppdl.purdue.edu/ppdl/soybean_rust.html.
"Preparing for Asian Soybean Rust" -- This Extension publication (ID-324) covers the basics about the fungal disease, how it spreads and control options. The publication can be downloaded online at http://www.ces.purdue.edu/extmedia/ID/ID-324.pdf. Printed copies can be ordered online by logging onto https://secure.agriculture.purdue.edu/store/item.asp?itemID=16906.
For additional information on soybean rust and where infection has been
confirmed, visit USDA’s rust observation Web site, at http://sbrusa.net.
Source: AgAnswers e-newsletter, Purdue University
Amy Fahnestock, May 30 2006, 18:13USDA Aphid, Rust Management Styles Differ
(Editor’s note: A brief explanation and description of the new features on USDA’s Asian soybean rust Web site - now called the PIPE Mapping Web site - can be found in the June issue of CropLife® magazine, p. 16. Here, Ohio State’s Ron Hammond provides a more in-depth explanation of the site’s new soybean aphid tracking tool.)
WOOSTER, OH -- Soybean growers have an added decision-making tool in scouting for the soybean aphid.
U.S. Department of Agriculture’s Pest Information Platform for Extension and Education, created last year to track the development of soybean rust throughout the United States, has added information to track and manage the soybean aphid. The site relies on reports from across the country on insect and disease development in sentinel plots.
However, the interpretation of the data on this Web site is not used in the same manner as with soybean rust, said Ron Hammond, an Ohio State University research entomologist with the Ohio Agricultural Research and Development Center.
"Growers will not use the aphid information like they use the soybean rust information," said Hammond, who also holds an OSU Extension appointment. "That’s the critical difference between this program for rust and the program for aphids that we have to make clear to growers. Rust may cover a lot of fields in an area, so if one field has it, others might be at risk for it so you may have to treat your field to prevent it. That isn’t the situation with insects. Finding the aphid in your area has nothing to do with your own fields. You cannot make any decisions based on what happens in any other field in your area. You have to sample each field individually."
Hammond and other entomologists are encouraging growers to maintain an integrated pest management (IPM) strategy when managing the soybean aphid, as with other field pests.
IPM is a strategy that involves constant field scouting and monitoring of pest development and recommends action taken only when insects reach damaging thresholds. IPM practices involve situations with individual crop fields. By contrast, the spread of diseases, like soybean rust, can impact several fields in an area, thereby requiring fungicide applications as a preventive or control measure.
The prediction that soybean aphid populations are expected to be low in Ohio this season further complicates the situation.
"The information on this Web site, as a research tool, can provide us with a lot of historical data to see where we’ve had problems and where thresholds have been reached," said Hammond. "We don’t want to see the information provided used in the wrong way. And if companies tell you that you should be spraying because aphids in nearby sentinel plots have hit threshold, then they are just trying to sell you a product."
Additionally, Ohio State researchers discount using insecticides in soybean fields when not warranted just to boost plant health.
"OARDC research has shown that spraying insecticides or fungicides in fields when not needed does not give an economic return," said Hammond. "Spraying when the aphid reaches the threshold of 250 insects per plant is where you get the best return, not as a preventive measure and not for plant health."
Ohio growers are encouraged to consult Ohio State’s Agronomic Crops Team Crop Observation and Recommendation Network (C.O.R.N.) newsletter for weekly news and recommendations on crop-related issues. The newsletter can be found at
http://agcrops.osu.edu
Visit:
http://sbrusa.net
Source: The Ohio State University
Amy Fahnestock, May 26 2006, 20:35More Research Needed to Find Value of Foliar Fungicides in SoybeansThe attention given to foliar fungicides for soybean production following the discovery of Asian soybean rust has in part caused growers to evaluate if there’s potential to increase yields in the absence of soybean rust, says Dean Malvick, assistant professor of plant pathology at the University of Minnesota. One initiative growers are evaluating is a foliar fungicide application for a "plant health" benefit.
"Some in the industry perceive that soybean yields haven’t increased like they could and some are looking at more intensive management," Malvick says. "They’re looking to see if there are additional management tactics or tools that can be used to increase soybean yields economically."
Rather than focusing on single inputs or factors that influence soybean yields, Malvick and many others prefer to look at multiple ways of achieving increased yields of soybeans. This approach incorporates the contribution of genetics, multiple diseases, nutrition, soil types, water, nematodes, insects, and stress to produce the final yield of a soybean plant.
Marty Draper, plant pathologist at South Dakota State University, summarized foliar soybean fungicide trials conducted in 2005 by multiple investigators at 65 locations across the north-central region of the Midwest. While all trials were absent of Asian soybean rust, some identified measurable levels of other diseases. Other trials may or may not have contained some level of secondary disease; however, they were not reported one way or the other.
Trial reports show that a foliar application with a strobilurin fungicide yielded at least 4 bushels per acre (bu/A) more than the unsprayed control only about one-third of the time. However, another one-third netted a positive effect on yield below 4 bu/A; and the final one-third showed a yield loss vs. untreated soybeans.
"What I see for the future is that additional trials will help us get a handle on when and where we might expect to see an economic and yield advantage of using fungicides," Malvick says. "It’s clear they don’t work well everywhere and in every situation.
"But there are some situations where they might be beneficial. Trying to understand what those situations are and where those locations are where growers could see a relatively high probability of return is being explored. There’s a quest to narrow down that window of where we can have a higher likelihood of getting a positive return."
Malvick stresses that it’s important for growers to remember that the primary function of fungicides is to control diseases. This follows the argument for growers to follow integrated pest management (IPM) principles, so the decision to use a control strategy is triggered by an identifiable problem. Elements of IPM include scouting and identifying pests or limiting factors, and then implementing appropriate strategies to reduce their impact.
"IPM in most situations is pest management, not pest prevention," Malvick adds. "While many are trying to understand when and where a fungicide application made without a clear disease or stress problem will pay off, growers should leave strips that are unsprayed in a field. This comparison will allow growers to more easily see if potential yield benefits are actually from fungicide applications."
Despite the pursuit to increase soybean yields in the absence of soybean rust, it’s important that growers don’t lose sight of this disease and the damage it can cause. Growers must be as educated about soybean rust and up to date as possible so they are aware of where soybean rust is and the likelihood of when it might become present and develop to damaging levels within their respective location.
When applications for Asian soybean rust are needed, growers should carefully select a fungicide. Dave Ruen, product technology specialist for Dow AgroSciences, says that fields will require curative activity if infected by Asian soybean rust. He adds it’s possible for fields to be infected and not show symptoms if infection has just started.
"By making the first application against soybean rust with a triazole-based product, such as Laredo fungicide, growers receive both preventive and early stage curative activity," Ruen adds. "Only the triazole class of chemistry offers this dual type of activity. Strobilurin fungicides provide only preventive activity, unless tank-mixed or premixed with a triazole."
Source: Dow AgroSciences LLC
Laredo fungicide is available for use on soybeans for the control of Asian soybean rust through Section 18 quarantine exemptions. The exemptions are valid through 2006 for use of this product in the states of Alabama, Arkansas, Colorado, Delaware, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland, Michigan, Minnesota, Mississippi, Missouri, Nebraska, New Jersey, New York North Carolina, North Dakota, Ohio, Oklahoma, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, Virginia, West Virginia, and Wisconsin. State limitations exist regarding the number of applications that can be made using approved Section 18 products. For a list of retailers who stock Laredo, call 1-800-258-3033. Always read and follow label directions.
Amy Fahnestock, May 30 2006, 12:47Don’t Underestimate Foliar Diseases In SoybeansFocusing Solely on Soybean Rust can Hurt Growers’ Yields
Since arriving in the United States in late 2004, soybean rust has dominated agricultural news. There is no shortage of information available to growers on the topic, as Web sites and meetings have popped up everywhere specifically to address the potential impact of rust. This information is necessary, as rust potentially poses a severe threat to soybean production, but experts warn growers not to let rust overshadow other late-season diseases that lower yields every year.
In any given year, Southern growers who choose not to make a soybean fungicide application can expect some degree of yield loss, according to Dr. Alan Blaine, Mississippi State University Extension soybean specialist.
"Foliar diseases are something that we have to deal with every year. They’re quite widespread," says Blaine, citing anthracnose, pod stem blight, frogeye leafspot, and late-season Cercospora as some of the more common diseases that thrive in hot, humid Southern weather.
"Our growers in the deep South are applying a whole new level of management to the crop that we didn’t do wide scale 15 years ago. A part of that management is attempting to control foliar diseases," he says. These management practices include earlier planting, the use of earlier maturing varieties, and timely applications of a foliar fungicide.
Before applying a fungicide application, Blaine encourages growers to consider their yield potential. In irrigated fields or high management situations, a fungicide application may give fields a boost to achieve higher yields. Fungicide applications may not offer substantial returns in drought situations or on some early planted fields. If a grower decides to spray for foliar diseases, Blaine encourages him to make the application between R3 and R4 (reproductive stages).
In numerous trials, Blaine and others have found the application of a strobilurin fungicide application to pay off. "Since the late 1990s, we’ve been averaging a 5.9-bushel yield increase with a strobilurin-based program. That increase is the average of over 130 on-farm trials and side-by-side comparisons," he says. Blaine’s findings are not unique to the South. In more than 570 in-field Syngenta trials across the United States, the company’sQuadris fungicide -- a strobilurin -- boosted yields an average of 5 to 6 bushels per acre (bu/A).
In 2005, Dr. Wayne Pedersen, soybean plant pathologist at the University of Illinois at Urbana-Champaign, noted 100 percent incidence of anthracnose stem blight in some fields following late-season rains. Through a series of trials funded by the Illinois Soybean Check-off Board and agrichemical companies, including Syngenta Crop Protection, Pedersen concluded that foliar diseases can impact yields, but timely applications of strobilurin fungicides applied around R3 to R4 can control those diseases and prevent yield losses.
Pedersen evaluated four to eight soybean varieties and 16 fungicide treatment combinations at eight locations, ranging from Metropolis in the far south to Dekalb, near the Wisconsin border. Only two locations did not have a significant yield increase, and they were very dry during pod fill. Across the varieties, the boost in yields was approximately 4.8 to 7.5 bu/A.
"What we’re seeing, without a doubt, is exactly what the Brazilian farmers have seen as well. There is yield loss due to lack of late-season disease control," Pedersen says. "The exciting part from my side of it is that I think we’re capturing a fair amount of yield we didn’t know we were losing. When you see a 12-bushel yield increase on a grower’s field, he gets excited and says, ’You mean every year I’ve been losing this?’ My answer to that is, ’I don’t know about every year, but the potential loss from late-season diseases is far greater than we ever thought.’"
However, the threat of soybean rust has caused some growers to deviate from this tried and true fungicide program. In 2005, many Southern growers postponed their fungicide application in hopes of treating foliar diseases and rust at the same time. Instead, rust never materialized, and they missed the window for a profitable foliar application.
Blaine understands growers’ fears. However, he thinks the economic benefits of an average 5.9 bu/A increase outweigh the negatives of an additional application, and he encourages growers to make the decision to spray for foliar diseases independently of rust. "I think we need to go ahead and make that shot when warranted whether we have rust or not, even if rust puts us in a two-shot program from time to time. Rust doesn’t overly concern me. I’ve seen it, and I know we have material that will control it," Blaine says. "I’m telling growers, ’We have already got your rust program paid for just spraying for other diseases.’ The return is much greater than what a fungicide program for rust will cost you.”"
If rust poses a threat, Blaine says growers may need to make modifications to their program. A combination application, such as Syngenta’s Quilt, that combines preventive and curative activity in one product might be a better choice. Quilt contains azoxystrobin, the active ingredient in Quadris, offering growers late-season disease control benefits as well. A new option in 2006 is tank mixing Syngenta’s Alto, a crop-safe triazole, with Quadris, providing preventive and curative activity in one application. Alto contains cyproconazole, which proved itself as a leading soybean rust treatment Brazil and recently received an EPA Section 18 for control of Asian rust on soybeans in the United States.
However, the basic premise of Blaine’s recommendation will remain the same. "Right now, my fungicide program is a strobilurin at the R3 to R4 time frame," Blaine says. "Rust or no rust, I’m going to have a strobilurin in my fungicide program. Fungicide will make growers money, year in and year out, on every acre they grow beans on if they plant timely."
Source: Syngenta Crop Protection, Inc.
Requests on behalf of several states have been submitted to include Alto on EPA’s approved Section 18 list for control of Asian rust on soybeans. The following states have requested an Alto Section 18 Quarantine Exemption from EPA: Alabama, Colorado, Delaware, Illinois, Indiana, Iowa, Kansas, Kentucky, Maryland, Minnesota, Mississippi, Missouri, Nebraska, New Jersey, North Carolina, Oklahoma, South Carolina, South Dakota, and Texas. As of this printing, EPA has granted Section 18 approval for use on soybean rust in Illinois, Iowa, Maryland, Minnesota, Missouri, Nebraska, and South Dakota. Check with your state prior to using or recommending Alto for control of Asian rust on soybeans.
As of this printing, Quilt received approval for use on Asian soybean rust under a Section 18 Quarantine Exemption in the following states: Alabama, Arkansas, Colorado, Delaware, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland, Michigan, Minnesota, Mississippi, Missouri, Nebraska, New Jersey, New York, North Carolina, North Dakota, Ohio, Oklahoma, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, Virginia, West Virginia, and Wisconsin. If your state is not listed, check with your state prior to using or recommending Quilt for this use.
Quadris, Quilt, and Alto are trademarks of a Syngenta Group Co.
Amy Fahnestock, May 26 2006, 20:37Surprise Asian Soybean Rust Hits Portions of MexicoA bout of Asian soybean rust left more than 20 soybean seed growers near Tampico, Mexico unexpectedly dealing with the disease. About 320 hectares, or 650 acres, were affected, resulting in defoliation and potential large yield losses.
Asian soybean rust infections began in January but became increasingly noticeable in March and April. "It caught these particular growers by surprise, and it hit them pretty hard," says Dr. Marty Wiglesworth, Syngenta technical brand manager, fungicides.
Seed beans are generally harvested at the end of April into early May, so the majority of the affected acres should be out of the ground. Mexican growers will begin planting more soybeans closer to the Texas border in late May. According to Wiglesworth, the time gap between harvesting the seed beans and planting additional soybeans may be good news for U.S. soybean growers.
"We cannot foresee whether the impact on the U.S. crop will be minimal. We don’t know at this point," Wiglesworth says. "It depends on whether there are nearby patches of volunteer soybeans or kudzu for Asian soybean rust to live on until the newly planted Mexican crop becomes susceptible at the R1 (reproductive) stage. Scouting fields is the prudent thing to do, and the universities and Syngenta are actively engaged in scouting activities."
Potentially, Wiglesworth says Asian soybean rust could be equated to the wheat rust that comes yearly out of Mexico and Texas into the Midwest. "If Asian soybean rust establishes itself on a regular basis in Mexico, one possibility is that it could follow a very similar pathway as wheat rust. Overwintering Asian soybean rust present in Florida and Georgia has a harder time moving directly into the Midwest unless there are unusual weather patterns, but Mexico could serve as a more consistent source into the Midwest. At this time, however, experts believe the current risk for rust in east Texas is low."
There are currently no effective fungicides labeled for use in Mexico for Asian soybean rust control, although agrichemical companies, including Syngenta, are currently pursuing emergency exemptions for rust specific fungicides.
More information about soybean rust is available from local Syngenta sales representatives by calling 888-SOYRUST or at
www.soybeanrust.com
For more information, visit
www.farmassist.com
Source: Syngenta Crop Protection, Inc.
Amy Fahnestock, May 26 2006, 20:44Go Ahead, Spray Your Way (From CropLife magazine, April 2006, p. 10, with additional details.)
HOW many hours has your staff spent trying to determine how to apply fungicide in your efforts to manage Asian soybean rust? Certainly nothing is cut and dried. What type of sprayer, nozzle, and even the spray droplet size are all variables to weigh and discuss.
There is good news: A number of application options provide equally effective coverage, you just need to choose what fits your production situation. That’s the message from a study conducted at The Ohio State University’s Ohio Agricultural Resarch and Development Center (OARDC) in Wooster, OH. These findings also apply when managing soybean aphids or other soybean diseases that develop similarly to rust.
"The goal of the study was to determine which spray equipment would be the most effective against soybean rust, " says Erdal Ozkan, an Ohio State University Extension agricultural engineer and one of the researchers of the project. The research team was made up of Ohio State plant pathologists and engineers from USDA Agricutural Research Station’s Application Technology Research Unit in Wooster.
"The disease starts from the lower part of the canopy and progresses toward the top. And by the time rust would arrive, say in Ohio, soybean plants may be in advanced growth stages, sometimes 3 to 4 feet tall with good canopy coverage. Penetrating the lower part of the canopy with applications is very challenging, " he says. "Despite the wide variety of fungicides available to control soybean rust, fungicide labels fail to clearly specify the type of application equipment or setup that would provide the best coverage. "
Ozkan and his team tested nine application set-ups, observing droplet coverage and deposition on a variety of artificial targets placed inside soybean plants in four replicated areas 50 feet wide and 150 feet long. Three types of sprayers (air-assisted, AirJet, boom sprayer, and boom sprayer with canopy opener), four nozzle types (hollow cone, flat-fan, TwinJet, and Turbo TeeJet), and three types of spray quality (fine, medium, and coarse) were used.
The Study Says …
The research findings include:
- If you’re working with a conventional sprayer, use nozzles that deliver medium spray quality rather than fine or coarse. These tend to provide better penetration of droplets inside the plant canopy and better leaf coverage.
- There’s been a lot of talk about the need to hit the target with two different angles of spray. This may provide better coverage if the canopy is not dense, but flat-fan nozzles with a single spray pattern and medium quality spray tended to perform better with dense canopies, giving better penetration of droplets inside the canopy.
- Air-assisted sprayers outperformed conventional sprayers with penetration of droplets and spray coverage.
- Adding a mechanical canopy opener can help boost your conventional sprayer’s coverage and penetration capabilities to nearly the air-assisted sprayer’s level. However, the canopy opener will not reduce spray drift.
- At 15 gallons per acre and seven miles per hour in dense canopy conditions, flat-fan nozzles provided better coverage and penetration into the canopy than hollow cone nozzles.
Additional information not included in the April issue of CropLife, page 10:
"We analyzed three ways to achieve our objectives," says Ozkan. "One way was to directly measure the efficacy of rust fungicides applied to soybean plants. Another was to use artificial targets implanted into the soybean canopy. And the third was to measure the amount of fungicide deposits on the leaves and stems of the soybean plant.
"Obviously, the first option was not available to us because luckily soybean rust didn’t show up in Ohio in 2005. And we only have part of the data analyzed regarding fungicide deposits on soybean leaves and stems, although preliminary data is showing similar application results as those achieved using the artificial targets. "
Data regarding fungicide deposits on soybean leaves and stems is expected to be completed by May.
Ozkan says that knowing which spray application is most effective in controlling soybean rust is important, given the nature of the disease.
The spray application recommendations are not limited to soybean rust, however. Ozkan says they also are applicable for managing soyben aphid or other soybean diseases, such as white mold, that exhibit similar growth characteristics to soybean rust.
Funding for the research was provided by the Ohio Soybean Council through soybean check-off, The Ohio State University Extension, OARDC, USDA-ARS, BASF Corp., Gregson Technologies, Jacto, Inc., Spraying Systems Co., Unverferth Equipment Co., and others. Information for this article was provided by The Ohio State University.
For a more detailed report on this study,
click here.
Amy Fahnestock, Apr 14 2006, 14:12Spanish Version Of Soybean Rust ID Card Available A free pocket-sized soybean rust ID card, published last year for soybean growers throughout the country, is now available in Spanish.
"Identifying Soybean Rust" is the result of a collaborative effort between USDA, Ontario Ministry of Agriculture and Food, and 22 land-grant universities.
The photo-laden, full-color ID card outlines soybean rust symptoms and differences to similar-looking foliar diseases, such as bacterial blight, bacterial pustule, downy mildew, frogeye leaf spot, and brown spot.
"Identifying Soybean Rust" is just one of several soybean rust resources available to retailers and their growers for the 2006 growing season. Both English and Spanish versions of the ID card can be obtained by contacting your state Extension office.
-- From The Ohio State University
Amy Fahnestock, Apr 10 2006, 12:40USDA Soybean Rust Detection Efforts PraisedUSDA’s Economic Research Service (ERS) estimates that the soybean rust early warning system is working on all levels of participation, increasing U.S. soybean grower profits by $11 million to $299 million overall in 2005.
The new ERS report evaluates the early warning system for soybean rust surveillance, reporting, prediction, and management during the 2005 growing season and concludes that information provided as part of the system helped to increase profits and mitigate damage caused by the fungus.
"Last spring USDA launched an early warning system to help ensure producers have easy access to all the best information and guidance on soybean rust," said Agriculture Secretary Mike Johanns. "I’m pleased that our efforts have been successful and even contributed to increased producers’ income. I encourage producers to continue their vigilance this year and use the soybean rust Web site to help make informed decisions in managing soybean rust."
The report, "The Value of Plant Disease Early Warning Systems: A Case Study of USDA’s Soybean Rust Coordinated Framework," examines the system that provides real-time, county-level forecasts of soybean rust detections in the U.S. to provide timely forecasts of soybean rust infections that could reduce yields.
ERS conducted the case study to evaluate the effectiveness of the coordinated framework, or early warning system. The study estimates that the information provided by federal, state, industry and academic partners increased U.S. soybean producers’ profits by a total of $11 million to $299 million in 2005, or between 16 cents and $4.12 per acre.
In 2002, USDA implemented a strategic plan in anticipation of a potential soybean rust find in the U.S., which established priorities of protection, detection, response and recovery. USDA agencies -- including the Animal and Plant Health Inspection Service; the Cooperative State Research, Education and Extension Service; the Risk Management Agency, and the Agricultural Research Service -- partnered with soybean industry organizations, state departments of agriculture, and many in the research and scientific communities to launch a coordinated framework.
Central to the coordinated framework is the USDA soybean rust Web site, according to the report. The one-stop federal resource provides growers, crop consultants, and others timely information on the extent and severity of soybean rust outbreaks and gives users up-to-date forecasts on where soybean rust is likely to appear.
The study uses USDA data on historical soybean yields, data from USDA’s Agricultural Resource Management Survey, estimated soybean rust damages from Brazil and Paraguay, and spore dispersion estimates based on an aerobiology analysis and historical experience with wheat stem rust. Using National Agricultural Statistic Service data, information from a Government Accounting Office (GAO) soybean rust report and research conducted by agricultural analysts, ERS also concluded that the timely soybean rust forecasts mitigated damage through preventive management activities, which included fungicide application recommendations.
The GAO report released in March also praised USDA’s efforts to provide timely information on Asian soybean rust detections. That report revealed that cooperators did a solid job of monitoring the disease and preparing America’s growers to handle outbreaks.
Soybean rust is caused by either of two fungal species, Phakopsora pachyrhizi, also known as the Asian species, and Phakopsora meibomiae, the New World species. The Asian species, first found in Louisiana in 2004, is the more aggressive of the two species, causing more damage to soybean plants. During the 2005 growing season, the fungus was found in nine states: Alabama, Arkansas, Florida, Georgia, Mississippi, Missouri, South Carolina, Tennessee, and Texas. In the current growing season, it has been found in Florida, Georgia, Alabama, and Texas.
To view the USDA report, click here.
USDA’s one-stop resource, www.usda.gov/soybeanrust, provides timely information on the extent and severity of soybean rust outbreaks in the U.S., Caribbean basin, and Central America. It provides users up-to-date forecasts on where soybean rust is likely to appear in the U.S., reports where the disease exists by county, refers growers to county Extension agents nationwide, lists the National Plant Diagnostic Networks laboratories, and links to other Web sites to give producers effective disease management options.
-- from USDA News
Amy Fahnestock, Apr 04 2006, 14:04Soybean Rust Map Adds New ColorUSDA has added a new color code -- red hatching -- to its Asian soybean rust observation map, which can be found on this site and also at
www.sbrusa.net.
The new color style, which looks like red diagonal stripes, will represent counties where known soybean rust-infected sites have been either destroyed or removed, according to USDA. Even with the removal of host material, it is likely that soybean rust may exist in other, as-yet undetected sites in that county.
When a county has had a positive detection and the plants are subsequently removed, a USDA Soybean Rust e-mail alert will be generated for that county. It will be listed in the chronology of positive detections on the Web site.
Several counties have had positive site(s) where the host was removed or destroyed: Brooks, Grady, and Thomas counties in Georgia, and Hidaldo County in Texas. These are now indicated on the soybean rust observation map by the red hatching.
Amy Fahnestock, Mar 24 2006, 13:52States Keep Eye On AlbertoThe latest updates on June 12 from Georgia and Kentucky for the week of June 5-9, 2006:
From Dr. Layla Sconyers, post-doctoral research associate at the University of Georgia’s Coast Plain Experiment Station:
"Soybean and kudzu sentinel (as well as mobile/non-sentinel kudzu) sites were examined this week in Georgia for soybean rust. Most of our soybean sentinel plots (MG-IV and MG-VI) are now at the V6-V8 growth stage, with some plots at first bloom (R1). Growers continue planting soybeans in the state.
"No soybean rust was observed this week on any of our samples.
"It continues to be hot and dry for most of the state. Sites previously infected with rust and destroyed (in Brooks, Grady, Miller, and Thomas counties) are still not showing ANY new signs of infection. Since no rust has been detected in these counties since winter, they have been colored green on the USDA Web site map at www.sbrusa.net.
"We are still closely monitoring these areas since rust is active in north Florida, and we will continue to examine these areas closely as Tropical Depression Alberto moves north. This system could possibly move spores north to Georgia, so we need to monitor this closely over the next few days."
And from Dr. Don Hershman, Extension plant specialist from the University of Kentucky:
"The only state reporting any significant sporulation of the rust fungus on kudzu is Florida. It has been very dry rain-wise, but some places have had nightly dews for 4 to 6 hours, and this is apparently all it takes to get spore development, assuming the fungus in already in the patch. There is no rust in soybean anywhere.
"Tropical Storm Alberta will be moving through the area with plenty of spores later today, but the path of the storm will take it away from us."
Amy Fahnestock, Feb 16 2006, 22:46USDA To Expand Soybean Rust ToolsNot only will USDA will continue to fund its current national soybean rust risk management tools, it will expand its offerings.
"The soybean rust sentinel plots, mobile team monitoring program, and online reporting system are important tools for our producers," says Agriculture Secretary Mike Johanns. "Timely information is essential to help farmers combat plant diseases and we are committed to providing it."
The newest component — the Pest Information Platform for Extension and Education — will provide information about other legume pests and disseases to growers.
The current online reporting system — created in time for the 2005 soybean growing season — is accessible via the "map" link on this Web site or at www.sbrusa.net. The real-time data system allows retailers and their growers to access up-to-date information — right down to the county level — of where Asian soybean rust has been confirmed. The mapping tool, according to a USDA press release, will continue "to include frequently updated commentaries from state extension specialists and national specialists discussing immediate and projected risks and control options." USDA’s Risk Management Agency (RMA) funded this $2.4 million component.
The press release also noted that "to complement the network, USDA will continue to conduct teleconferences, workshops, and organize Extension field visits to prepare first detectors to scout for pest and disease problems, to obtain diagnostic confirmation when a suspected problem is found and to manage the information for timely incorporation into the risk management map. Training modules will also be produced for crop advisors and producers about how to use the map system and what the risk management alternatives are, based on a three-tiered (low, medium, high) risk advisory."
The soybean rust risk management tool is a joint effort of USDA’s Cooperative State Research, Education and Extension Service (CSREES), RMA, and Animal Plant Health Inspection Service. CSREES is implementing its part of the system through its land-grant university partners, the Cooperative Extension System, the Regional Integrated Pest Management Centers, and the National Plant Diagnostic Network.
Amy Fahnestock, Oct 28 2005, 18:09Rust Found In Volunteer SoybeansNews of Asian soybean rust in their area hasn’t sent Seminole County, GA, growers into a panic, according to local retailers. USDA reported on April 27 that rust had been confirmed on volunteer soybeans in Seminole County, GA -- the first report of rust in soybeans in 2005. USDA also says it is probably present in kudzu in the area.
Rust previously had been confirmed in kudzu in three Florida counties -- Pasco, Hernando, and Marion. Seminole County is at the very bottom left corner of the state, bordering Florida and Alabama.
Growers have yet to plant any soybeans in the area this season, says Melvin Fox of Triangle Chemical in Donalsonville, GA. A staff member at UAP GA Ag Chem, Inc. in Donalsonville, agreed. Cotton is just beginning to go into the ground, with the peanut crop started around April 21.
Peanuts, cotton, and field corn are the primary crops in Seminole County, says Rome Ethredge, county Extension coordinator. "Here, soybeans are planted after the field corn," he says. "We’re far enough south to doublecrop." The soybeans are typically planted in late July/early August, when rust could still be present.
Although none of Triangle Chemical’s soybean grower-customers had called with concerns or questions the day after the confirmation was announced, Fox expects mixed reactions. "Some will spray a preventive fungicide and some might wait and see if they get it before spraying," he says.
Rust had already been affecting planting decisions in the county before this new discovery. "I talked to a grower who plants soybeans after corn under irrigation pivots, and he said that bean profits are so slim, if he has to buy fungicides he probably won’t plant soybeans this year," Ethredge says. "We’re glad it doesn’t affect peanuts, even though they are a legume."
One crop that does concern local growers is snap beans. Around 1,500 acres of snap beans are grown in the county annually, and rust could have a serious financial impact. "Our growers are monitoring the snap beans very closely, which are 6 inches tall right now and growing strong," Ethredge says. "We looked at the fields very closely yesterday. A lot of the older chemistries are protective, while the newer ones have a kickback/curative ability, and growers will have to make some critical decisions."
USDA is advising retailers and growers to continue scouting volunteer soybeans and non-hosts, especially in Florida, Georgia, Alabama, Mississippi, Louisiana, and South Carolina.
For those looking for more information on which fungicides to use in their specific scenario, a new manual, "Using Foliar Fungicides to Manage Soybean Rust," is available to help walk a grower through rust management and proper fungicide applications.
"The manual outlines several different scenarios about which types of materials producers can use depending on where rust is in the U.S. and whether it’s been found in their field or not," explains Anne Dorrance, an Ohio State University Extension plant pathologist with the Ohio Agricultural Research and Development Center in Wooster, OH.
The result of a multi-state, multi-organization effort, the 60-page booklet covers such topics as a soybean rust overview, making fungicide decisions, fungicide basics, application basics, aerial application tips, bee toxicity, and an overview of similar diseases. It includes articles, illustrations, photographs, maps, tables, and charts contributed by the nation’s leading land grant university plant pathologists, as well as experts from Canada.
"This resource is unique in that it lays a solid foundation on which we will build our soybean rust fungicide experience in the U.S. We may not yet know all there is to know about managing soybean rust with fungicides in the U.S., but no other resource exists in the world which represents so much collective wisdom on soybean rust," said Don Hershman, a University of Kentucky Extension specialist for the Department of Plant Pathology, and an editor of the publication. "The editors and authors strove to develop a publication that was both easy to understand and follow, but at the same time summarized detailed scientific information in a way that was both logical and practical. I believe we have succeeded."
Added South Dakota State University Extension plant pathologist Martin Draper, "This publication pulls together the best and most complete information known on management of soybean rust. We have a lot to learn about how this pathogen will interact with soybeans in our environment, but it is our sincere hope that the information in this publication will help growers be prepared and realize a lesser impact from soybean rust." Draper also is an editor of the fungicide manual.
The publication is available from your state Extension Service or online at www.oardc.ohio-state.edu/SoyRust/index.htm, where chapters can be downloaded in PDF format.
The USDA Soybean Rust Information Site can be accessed via this Web site where you see the USDA Rust Tracker icon. The Web site is updated based on weekly evaluations of the sentinel plots in each state. Areas that are scouted, but where no rust is found, are marked in green. Scouted areas with confirmed soybean rust sightings are indicated in red.
Amy Fahnestock, May 05 2005, 11:50Fourth Rust Finding In Florida KudzuA fourth county in Florida – Dade County – has now confirmed soybean rust in kudzu, according to USDA’s Soybean Rust Information Web Site. Rust previously had been confirmed in kudzu in three Florida other counties -- Pasco, Hernando, and Marion.
USDA reported on April 27 that rust had been confirmed on volunteer soybeans in Seminole County, GA -- the first report of rust in soybeans in 2005. USDA also says it is probably present in kudzu in the area. Seminole County is at the very bottom left corner of the state, bordering Florida and Alabama.
USDA is advising retailers and growers to continue scouting volunteer soybeans and non-hosts, especially in Florida, Georgia, Alabama, Mississippi, Louisiana, and South Carolina.
USDA’s rust Web site can be accessed via the USDA Rust Tracker icon on this site (click on the "Back" key). The Web site is updated based on weekly evaluations of the sentinel plots in each state. Areas that are scouted, but where no rust is found, are marked in green. Scouted areas with confirmed soybean rust sightings are indicated in red. Currently just the four Florida and one Georgia counties are marked in red.
In other news, Georgia, Wisconsin, and West Virginia have joined the ranks of states that have issued a Section 18 emergency exemption for Laredo EC, Laredo EW, and PropiMax fungicides for the control of Asian soybean rust. Custom applicators and growers will be able to make a maximum of two applications of approved Section 18 products. For Georgia growers, the timing couldn’t be better because of the discovery of rust in volunteer soybeans just a few days before.
The Laredo products contain the active ingredient myclobutanil and PropiMax contains propiconazole as its active ingredient. Both fungicides provide preventive and curative control of soybean rust.
States that already have issued Section 18 emergency exemptions for these products are Alabama, Arkansas, Delaware, Florida, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland, Michigan, Missouri, Mississippi, North Carolina, North Dakota, Nebraska, New York, Ohio, Oklahoma, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, and Virginia.
Amy Fahnestock, May 05 2005, 11:46Three Sprays ApprovedBrazilian soybean growers sometimes need a third fungicide application to fight Asian soybean rust – and now, if conditions warrant it, U.S. growers will have that same flexibility. EPA has amended the Section 18 exemptions for soybean rust-approved fungicides to allow up to three applications instead of just two.
The EPA amendment includes all products already given a Section 18 exemption for Asian soybean rust and those that might be approved in the future, although each state Department of Agriculture will have final discretion.
A new expiration date for all of the approved Section 18 exemptions for use in soybean rust will be Nov. 10, 2007, for all states and all products.
Brazilian soybean growers sometimes need a third fungicide application to fight Asian soybean rust – and now, if conditions warrant it, U.S. growers will have that same flexibility. EPA has amended the Section 18 exemptions for soybean rust-approved fungicides to allow up to three applications instead of just two. Click here to view approved the fungicide list
Amy Fahnestock, Apr 18 2005, 19:07Rust Impact On Soybean Planting A BustAsian soybean rust has not had the major impact on U.S. growers’ 2005 planting decisions that some experts feared, according to USDA’s Prospective Plantings report. The report was released at 8:30 a.m. March 31, effectively squelching speculation on how growers would react to this potentially devastating disease.
Soybean growers intend to plant an estimated 73.9 million acres. That’s 2 percent less than the record-setting 2004 soybean acreage of 75.2 million.
USDA’s National Agricultural Statistics Service (NASS) included questions on Asian soybean rust in its March Agricultural Survey, which surveys randomly selected growers in the U.S. about their planting intentions for a number of crops, including soybeans. This year’s questions sought to measure grower awareness of Asian soybean rust and how its discovery in the continental U.S. has affected their planting decisions for the 2005 crop. Growers in the 31 soybean-producing states were asked if they had seen, read, or heard any information about Asian soybean rust. A resounding 89 percent responded positively. The survey found that awareness was highest among farms with 500 to 999 intended soybean acres and lowest among farms with 1 to 99 intended soybean acres.
Growers who responded "yes" were then asked if Asian soybean rust was a decisionmaking factor in their soybean planting intentions for 2005. A "yes" response resulted in two more questions. Did Asian soybean rust result in an increase, decrease, or no change in your soybean planting intentions? By how many acres did your soybean intentions change due to the Asian soybean rust?
The survey results show that 11 percent of soybean farm operators in the 31 soybean-producing states felt Asian soybean rust was a decisionmaking factor in their soybean planting intentions for this year. According to NASS, farms with 1 to 99 intended soybean acreage were least likely to consider Asian soybean rust as a factor in their planting decisions.
NASS reports that when Asian soybean rust was a factor in planting intentions, 49 percent of soybean growers decreased their intended soybean acreage, while only 9 percent increased their planting intentions. The greatest percentage of growers that have decreased their soybean planting intentions because of Asian soybean rust were those in the Delta states (Arkansas, Louisiana, and Mississippi) and Southeast region (Alabama, Florida, Georgia, and South Carolina), where 63 percent decreased their soybean planting intentions.
The remaining 42 percent of growers told NASS that even though Asian soybean rust was a factor in their decision, it had not changed their planting intentions as of March 1.
Click here for the complete Prospective Plantings report, including regional level data on intended soybean acreage and the impact of Asian soybean rust. The report also includes 2005 planting intentions for corn, wheat, cotton, and other crops.
Amy Fahnestock, Apr 04 2005, 12:25Crop Insurance Deadline March 15Retailers: Make sure that your grower-customers are aware that the deadline for purchasing crop insurance is Tuesday, March 15.
Crop insurance policies are available in individual producer-based insurances and group plans.
Crop insurance is critical for covering losses caused by Asian soybean rust — but only if the grower has taken adequate control measures. "A farmer has to use what they call good farming practices," says George Patrick, a Purdue University agricultural economist. He notes that growers should follow the advice of your staff agronomist about what is adequate to control rust. "If there were a rust outbreak, the farmer would be expected to try to control it. They’d have to spray fungicide, put it on it a timely manner, and in adequate quantity."
Don’t forget to check out the CropLife Technology section in the April issue of CropLife® magazine for details on how retailers can help their growers keep accurate records on fungicide applications for Asian soybean rust.
Amy Fahnestock, Mar 10 2005, 21:03Commodity Classic Report: Rust AcceptanceAt the Commodity Classic in Austin, TX last week, a record crowd of corn and soybean growers gathered for a heaping helping of fellowship, education, and fun. As an editor of a retailer-centric publication I always feel slightly out of place at this show, but it is certainly interesting to see how manufacturers are marketing themselves to the grower audience. Here are some of the takeaways from this event:
RUST ACCEPTANCE. One observation I would forward is that growers now have a more businesslike attitude towards controlling Asian soybean rust. There was none of the panic and hand-wringing I might have expected a few months ago — folks seem to be quietly preparing for a possible invasion as best as they can.
In conversations with crop protection chemical companies, many are privately expressing concern that the onslaught of information this fall and winter would lead to undue panic, and they are trying to balance concern with control in their messages. That said, no one really had an answer to the question, "What if there is suddenly a positive detection in Iowa?"
BEAN VARIETIES HERE AND THERE. I was talking to Harold Reetz at the Potash & Phosphate Institute about Brazil lessons learned — Harold was not at Commodity Classic because he was out on a tour of Brazil — and he said that soybeans grown in South America do not resemble those grown in the Midwest, so there may be even more we do not know about how Midwest soybeans will react to a rust outbreak. Just one more uncertainty among many.
DO NOT SKIMP ON THE PROGRAM. Just about everyone was advising that cutting back on a total agronomic program for soybeans for the sake of a rust application is taking one step forward and two back, which is good news for retailers. Fertility in particular is one place growers may try to scratch out some savings, but they do so at great risk. Total plant health is critical to beating rust, not just fungicide applications.
That is all from Austin . . . stay tuned for updates in the days to come!
Paul Schrimpf, Feb 28 2005, 22:02Fair Insurance Claims A Good PolicyFile this under the category "Inadvisable Business Practices."
USDA’s Department of Agriculture Risk Management Agency (RMA) will have a very low tolerance for what it terms "innovative" crop insurance promises to attract growers.
For example, a dealership in Nebraska sent letters to its customers. The letter promised that if the grower purchased all other ag chemical inputs from this dealership, the dealer would then provide a letter stating that no fungicides were available for soybean rust, ensuring a crop insurance pay-off for the grower.
"This didn’t go over well with us," says Dave Bell, branch chief of USDA’s RMA Loss Adjustment Standards Branch. This branch writes the policy which insurance agencies use to determine if a grower qualifies for a crop insurance payment. "This is the type of thing we don’t want to happen. Let’s say a producer thinks this letter will work, taking it to his insurance agent. The agent is going to ask, ’This was the only fungicide dealer within a 150-mile radius of you?’"
While the agency cannot directly punish dealerships making misleading statements, it did make it clear to the insurance agencies in the retailer’s area that this specific letter would not be sufficient for a crop insurance claim.
Crop insurance will cover for losses due to Asian soybean rust damage "if the producer follows recommended spraying practices for fungicides," Bell says, including if either fungicides or sprayers are not available. The coverage level is determined when the grower signs up for the insurance.
If the grower chooses not to incur the cost of fungicide spraying when both fungicide products and sprayers are available, he will not qualify for an insurance pay-off. "He’s elected to take that reduction, so we’re not going to pay for that," Bell explains.
Amy Fahnestock, Feb 11 2005, 21:41
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