Cytogenetic and morphological features of common wheat hybrids obtained with the use of irradiated pollen of Aegilops triuncialis L.

Common wheat Triticum aestivum was crossed with the species Aegilops tr tri uncialis using gamma-irradiated at the doses of 0.75, 1.5, 5.0, 10.0, 13.0, and 15.0 kRad and nonirradiated pollen of the wild species. Meiotic chromo some pairing was analyzed in the hybrids of the first generation. Polymorph ism of the wild species for the ability of its chromosomes to pair with com mon-wheat chromosomes was established. However, the efficiency of the suppr ession of the 5B system of common wheat was lower than in Ae, speltoides. T he use of pollen irradiated at doses of 0.75 and 1.5 kRad allowed us to inc rease the yield of hybrid plants with respect to the control variant withou t applying biotechnology. the stimulative effect of pollen irradiation on t he frequency of chiasma formation in hybrids was found to be caused by the increased frequency of multivalent formation at an irradiation dose of 0.75 kRad, and owing to bivalent chromosome pairing at a dose of 5.0 kRad. This permits recombinant wheat genotypes that combine pest resistance with a co mparatively high productivity and high grain quality to be obtained.