Report to North American Millers’ Association
BYDV Evaluations – University of Illinois – 2013
Frederic L. Kolb
Objective: Our objective was to evaluate barley yellow dwarf virus (BYDV) tolerance for breeding lines from oat breeding programs.
Methods: Briefly, the evaluation procedure is as follows. We planted two replications of entries to be evaluated in hills in the field. About the time that the hills were planted in the field we also began the multiplication of virus-carrying aphids. We have maintained cultures of Rhopalosiphum padi carrying the PAV strain of BYDV for many years. Because BYDV cannot be mechanically transmitted the only way to inoculate plants with BYDV is to infect the plants with viruliferous aphids. Aphids were collected from the cultures, mixed with corn meal, and a standard volume of the aphid/cornmeal mixture is applied to each hill. After allowing about 3-5 days for aphids to infect the plants, the field was sprayed with an insecticide. After the plants had headed and stem elongations was completed, but while the plants are still green, each hill was evaluated for BYDV tolerance.
Hills were evaluated based on a 0 -9 scale where 0 equals no symptoms and 9 equals very severe symptoms (essentially dead). Very susceptible genotypes fail to head. The evaluation is based on amount of tillering, amount of stunting, extent of chlorosis, and amount of blasting in the panicles.
South Dakota State Univ.- 670 hills
Univ. of Wisconsin – 110 hills
Univ. of Saskatchewan 93 hills
Univ. of Minnesota – 128 hills
Louisiana State Univ. 142 hills
North Carolina State Variety Trial- 20 hills
Uniform Midseason Oat Nursery – 72 hills
Uniform Early Oat Nursery – 56 hills
Sunoat Winter Oat Nursery – 44 hills
Uniform Winter Oat Nursery – 50 hills
Cooperative Naked Oat Test – 14 hills
In addition to the spring and winter oats listed above we planted and inoculated 180 hills of spring barley and 180 hills of spring wheat for Ruth Dill-Macky, University of Minnesota. For all of these spring wheat and spring barley lines we grew both uninoculated control hills and inoculated hills. Ruth came to Urbana and did the evaluations on her material.
We also grew and evaluated 578 hills of winter wheat (plus 578 control hills) in cooperation with Gina Brown-Guedira, ARS-USDA at NC State. These lines were phenotyped for BYDV tolerance as part of an association mapping project on soft red winter wheat.
The oat BYDV nursery was planted on April 6, 2013. Excellent stands were obtained. The hills were inoculated on April 26and 29, 2013. Soil moisture was adequate for most of the season. BYDV symptoms were good in the nursery. All of the hills were evaluated for BYDV tolerance after heading had occurred and stem elongation had ceased. Ratings were done about June 24-28, 2013.
BYDV evaluation data were sent to the cooperators and coordinators of the uniform nurseries in electronic files via e-mail. Data were sent to individual cooperators on July 10, 2013.