Bread wheat x Agrotricum crosses as a source of immunity and resistance to the PAV strain of barley yellow dwarf luteovirus

Abstract

The Agrotricum line OK7211542 (2n = 56) was immune to the Cloutier isolate, which belongs to the PAV serotype of barley yellow dwarf luteovirus (BYDV). Through a process of selection for BYDV resistance and threshable phenotypes with wheat-like seeds, wheat-like F7-derived lines were obtained from Triticum aestivum7211542 crosses. Some of these were immune to BYDV and had 44 chromosomes. Resistant lines with 2n = 42 chromosomes or slightly higher chromosome numbers were also obtained. The low frequency of expression of immunity in the bread wheat background over many generations suggests that more than one gene is involved. These results are a first step towards the creation of wheat cultivars immune to BYDV. However, successful introgression will necessitate a transfer of immunity associated with a smaller amount of alien chromatin in the wheat genome. © 1994.