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Copyright Virginia Tech
  
Virginia Asian Soybean Rust Virginia Soybean Rust and Aphid Monitoring Program
2007 Virginia Soybean Rust Monitoring Program The Virginia Soybean Rust Monitoring Program began in 2004 and has undergone some expansion since that time. The goal of this program is to ensure that an early warning system is in place for soybean rust so that significant soybean yield losses from this pest is avoided. Additionally, the program aims to ensure that fungicides are used judiciously, only when necessary, and at the proper time.
During 2007 26 commercial soybean plots in major soybean production counties were monitored in addition to 10 USDA sentinel plots. Since previous experience demonstrated that early detection of soybean rust is possible only with microscopic examination of incubated soybean leaflets, the 2007 program relied upon laboratory examination of collected soybean leaflets by plant pathologists.
Additionally in 2007, a pilot spore trap project, which can detect as few as 1 to 2 soybean rust spores collected in a filter trap, was implemented in Virginia. Spores are detected and identified with a nested real-time PCR (polymerase chain reaction) assay. Assays were conducted in the Plant Disease Clinic. The goals of this project were to gather more information on rust spore movement and to target survey sample collection to locations where Asian soybean rust spores were confirmed deposited. For more information on this project see the Spore Monitoring Project page.
Sentinel plots samples were collected on a bi-weekly (during vegetative stages) and weekly basis (during reproductive stages) and examined and tested by plant pathologists at the Eastern Shore Agricultural Research and Extension Center, Plant Disease Clinic and Tidewater Agricultural Research and Extension Center. Examination and testing of leaflets from the commercial field plots was performed by plant pathologists at the Tidewater Agricultural Research and Extension Center. A total of 264 samples were examined from USDA sentinel plots and 166 samples from commercial fields during 2007.
Fortunately, in 2007 in Virginia , as in the previous year, soybean rust disease did not appear until the soybean crop was at a developmental stage at which the disease was no longer a threat to crop yields. Samples positive for soybean rust were confirmed by microscopy and ELISA at the Tidewater Agricultural Research and Extension Center. Numerous samples were processed every week during the growing season with negative results until the initial finds of rust on October 19. Again, the Virginia program demonstarted the ability to detect soybean rust during the initial phase of development and before crop damage occurred. Therefore, Virginia growers may be confident in the control recommendations that are generated from this monitoring program.
 The chronology of soybean rust detections in Virginia soybean fields by county is listed in the table below:
 For further information visit the national IPM-PIPE website.
During 2006 all soybean leaflets collected from USDA sentinel plots were examined in the laboratory by plant pathologists for symptoms and signs of soybean rust. This is because early symptoms of soybean rust are difficult to detect and may be overlooked, in addition to other limitations associated with detection in the field. A total of ten USDA sentinel plots were planted with three different maturity groups in the spring. Leaflets were collected by VCE cooperators and sent to laboratories (Plant Disease Clinic at Virginia Tech, Tidewater AREC, and the Eastern Shore AREC) at Virginia Tech where they were checked for the presence of the soybean rust fungus by stereoscopic magnification, serological testing and/or real-time PCR (polymersase chain reaction) testing.
Strips in commercial fields planted with an early-maturing soybean variety were also monitored to serve as an early warning system for soybean rust.
 Fortunately, during the 2006 Virginia soybean growing season Asian soybean rust arrived in Virginia after the Virginia soybean crop was no longer at risk of crop loss from this disease. The Asian soybean rust pathogen was first identified in Virginia from soybean leaflets collected from both a commercial field and a sentinel plot field in Suffolk county on 10/19/06. Subsequently, The fungal pathogen was identified in the following additional Virginia counties: Accomack, Chesapeake, James City, King and Queen, Sussex, Greensville, Southampton, Isle of Wight, Virginia Beach, Prince George, Gloucester, Middlesex, New Kent, Surry, Mecklenburg, Brunswick and Northampton--bringing the total counties in Virginia with soybean rust to 18. In 2005 90 commercial fields were scouted weekly from June through early October and 1700 field observations were made. Through funding from the Virginia Department of Agriculture and Consumer Services and funding for sentinel plot surveys through USDA, the Virginia Soybean Rust Monitoring Program was made possible in 2005. Other funds from USDA via the Southern Plant Diagnostic Network helped make this survey work possible.
During the Virginia 2005 soybean rust survey soybean rust was not identified in Virginia.
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Virginia IPM |
Virginia Cooperative Extension |
IPM in the Department of Entomology |
Nematode Assay Laboratory |
Plant Disease Clinic |
Weed Identification Laboratory |
Insect Identification Laboratory
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