GENETIC-ANALYSIS OF RESISTANCE TO LOW-TEMPERATURES IN WHEAT

Tolerance to low temperature is one of the most important component of winter hardiness in winter wheat. In the process of creation new wint er wheat varieties resistant to low temperatures it is important to kn ow the genetics of this character. Seven wheat varieties Nea, Amigo, S ava, Rana Niska, Saitama, UPI 301, NS-5260 and their F-1, F-2, BC1, an d BC2 generations were used to determine the genetic base of low tempe rature resistance. The mode of inheritance observed in most of the F-1 hybrids was partial dominance, although some cases where the parent w ith the higher or lower mean value dominated were also recorded. In th e F-2 generation, intermediacy was also the predominant mode of inheri tance. In Noa x Sava and Noa x Rana Niska both additive and dominant g ene effects were found. Frost tolerance was under control of additive genes in cross Noa x Amigo, Saitama x Sava and NS-5260 x UPI 301 and d ominant genes in Saitama x Rana Niska. In the process of winter wheat breeding the most importance have combinations in which additive gene effects predominate, since those crosses have greater chance to fix th e favorable genes responsible for cold tolerance. The selection of pro geny tolerant to low temperatures from those combinations should be mo re successfully.