Hybrid necrosis determined by two dominant genes Ne1 and Ne2. The wheat varieties may be divided into non-carriers and carriers either one, or other necrosis gene. Obviously, that the frequent use of certain carriers-varieties as parents in crosses has promoted the distribution of the necrosis genes. This became an important problem for practical plant breeding. The investigation of the authors showed that any variety of winter and spring wheat of Kazakhstan, which have been extensively used in crosses are heterogenic carriers of Ne2 gene. Using heterogeneity, it is possible from variety-carriers of dominant genes to secure lines deprived of these genes and to frame varieties free from them. The forced method was used for crosses 10-30 ears marked by labels of plants every of heterogenic variety to the Grecum 476 - donor Ne1 gene. Among F1 hybrids were a perfect vitality, sublethal and full lethal. The lines of variety in F1 which absent a necrosis were selected. The breeding of this lines are utilized for developing non-carrier of the variety.

Key words: genes Ne1, heterogeneity, hybrid necrosis, Ne2, plant breeding