Generation Mean Analysis of Inheritance of Resistance to Barley Yellow Dwarf in Crosses Involving Bates Spring Oats. J. L. Gellner, Former Graduate Research Assistant, University of Missouri, Columbia 65211. D. T. Sechler, Professor, Department of Agronomy, University of Missouri, Columbia 65211. Plant Dis. 70:795-797. Accepted for publication 3 February 1986. Copyright 1986 The American Phytopathological Society. DOI: 10.1094/PD-70-795.

The spring oat cultivar Bates, resistant to barley yellow dwarf disease (BYD), was crossed with Allen, a cultivar susceptible to BYD, and with Mo.06234, an advanced line resistant to BYD. Parental, F₁, F₂, and both backcross generations were grown for each cross in randomized complete block designs with three replicates. At the three-leaf stage, the plants were infested with viruliferous Rhopalosiphum padi. Data on tiller number, plant height, seed yield, and percent leaf reddening were recorded on individual plants. When a genetic model with additive and dominance effects was fitted to the generation means, only percent leaf reddening in the Bates × Allen cross showed an acceptable fit. A genetic model including epistatic effects was then used. From the significance of the epistatic effects in both crosses, we conclude that inheritance of resistance to BYD is more complex in the Bates × Mo.06234 cross than the Bates × Allen cross.