Abstract: 【Objective】 The objective of this research is to explore the genetic characteristics of new eco-genetic male sterile line BNS, to provide a theoretical guidance for breeding of wheat, and to lay a foundation for the further study on abortion mechanism of BNS. 【Method】 Reciprocal combinations between BNS and eight varieties ( lines ) were constructed to evaluate the cytoplasmic effects in BNS male sterility. Fertilities of F1 and F2 generations from cross of BNS/Shannong 055525 were analyzed in successive three years to obtain the optimal mode by applying the major gene plus polygene model of quantitive traits, and genetic parameters were also estimated. 【Result】 The fertility of BNS was controlled chiefly by nuclear genes, but cytoplasmic effects existed in some varieties (lines). The fertility of F2 populations showed a continuous distribution, and had obvious multi peak or skew phenomenon. The fittest genetic models was E_1, and that is the mode of two additive-dominant-epistasis major genes plus additive - dominant and additive-dominant gene. The major gene heritability was 72.5%-79.7%, and the major gene heritability was 4%-11.6%. The proportion of environmental variance was 8.8%-23.6% in phenotype variance. Male sterile gene expression in BNS was mainly regulated by the temperature, which leading to the changes of F2 seed setting rates and genetic parameters.【Conclusion】 The male fertility in BNS was controlled by two major genes plus polygene, and a certain amount of cytoplasmic effects was preliminarily found . The two major gene have more effects on the fertility, and their additive effect are much more than their dominant effects. The male sterile lines transformed or improved from BNS might be selected in early generations to enhance the efficiency of breeding.

Key words: wheat , thermo-photo-sensitive male sterility , major genes plus polygene