Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/4/1999
Publication Date: N/A
Citation: Porter, D.R., Burd, J.D., Shufran, K.A., Webster, J.A. 1999. Pyramiding greenbug resistance genes in wheat [abstract]. Agronomy Abstracts. p. 70.
Technical Abstract: Durable resistance to greenbug, Schizaphis graminum (Rondani), in wheat is a goal of wheat improvement teams, and one that has been complicated by the regular occurrence of new damaging biotypes. Simulation modeling studies suggest that pyramiding resistance genes provides more durable resistance than sequential release of single genes. We examined this theory by pyramiding genes in wheat and testing with greenbug biotypes that were identified in the field. Resistance genes Gb2, Gb3, and Gb6, and pyramided genes Gb2/Gb3, Gb2/Gb6, and Gb3/Gb6 were tested for effectiveness against biotypes E, F, G, H, and I. By comparing reactions of plants with pyramided genes with those with single resistance genes, we found that pyramiding provided no additional protection over that conferred by single resistance genes. Based on the results of this test, we concluded that the sequential release of single resistance genes, combined with careful monitoring of greenbug population genetics, is the most effective resistance deployment strategy.