Selection for Barley Yellow Dwarf Virus Tolerance in F2 Oat Populations in the Greenhouse

Abstract

Barley yellow dwarf (BYD) is an important viral disease that reduces grain yield in small grains. Breeders usually do not screen for barley yellow dwarf virus (BYDV) tolerance prior to selection of homozygous lines from segregating populations. If early generations of segregating populations could be screened in the greenhouse to increase the frequency of BYDV‐tolerant genotypes, the overall efficiency of selection would be improved. The objective was to determine if selection for BYDV tolerance in four F2 populations of spring oat (Avena sativa L.), which resulted from crosses of tolerant × tolerant parents and sensitive × tolerant parents, is effective in increasing the frequency of tolerant genotypes in the F4. F2 populations grown in the greenhouse were infested with viruliferous oat‐bird cherry aphids (Rhopalosiphum padi L.) that had been reared on plants infected with the BYDV PAV‐IL isolate. Response to selection was evaluated in the F4 in the field using the same PAV‐IL isolate. Selection in the F2 generation was moderately effective in increasing the frequency of tolerant genotypes in the sensitive × tolerant crosses, but was not effective in changing the mean BYDV tolerance in tolerant × tolerant populations. Heritability estimates calculated in 1990 and 1991 were high (0.5–0.8 and 0.8–0.9, respectively) and confirm that selection based on inoculated hills in the field should be effective in eliminating sensitive genotypes.