The use of wheat-alien and Aegilops-rye amphiploids for introgression of genetic material to wheat (Reprinted from Wheat: Prospects for global improvement, 1998)

An introduction of genetic material from rye, Aegilops and Elymus into durum and common wheat by crossing the wheat species with different amphiploids, has been attempted. Meiotic studies of the hybrids demonstrated that the wheat Elymus sibiricus amphiploid contained several (two or three) genes suppressing the activity of the wheat homoeologous pairing control system. Somatic chromosome studies of the hybrids revealed that the distributions of the alien chromosomes transferred to the second hybrid generation did not correspond to random (0.5 + 0.5)(2)k and binomial (p + q)(2k) distributions. An essential amendment for gamete and zygote viability, allowing the approximation of distributions by binomial equation, is discussed. The preferential E. sibiricus chromosome transmission was observed. The first backcross was found to be a critical stage while using the Aegilops-rye amphiploids for production of wheat introgressive forms. Stabilisation of the somatic karyotype and improvement of the meiotic regularity was observed in a number of generations. The isolation of stable cytological lines in BC3 was found to be possible.