Research On Combining Ability And Genetics Of YS-Type Thermo-Sensitive Male-Sterile Wheat Line And K-Type Male-Sterile Wheat

The use of hybrid vigor in wheat is in a very important position. In this study, the method of non-complete diallel model was used in the combing ability of K-type wheat male sterile line and YS- type wheat male sterile lines. And on this basis, plant quantitive characters genetic model was elected to analysis fertility gene in the two types male sterile line. Aims to find a better understanding of male sterile fertility regulation and molecular mechanisms, and provide a theoretical basis. The main findings were as follows:1. 21 crossing combinations were made by 3 A lines(1 K-type wheat male sterile line,2 YS- type wheat male sterile lines) and 7 R lines with the method of non-complete diallel. Seven characters on plant height,plant length of spike, spikes per plant,spikelets per spike,kernels per spike,1000-grain weight and grain yield were analyzed by SAS data statistics system. The result showed that:The effects of general combining ability(GCA)of the characters on 10 parents and specific combining ability(SCA)of wheat combinations showed that they reinforced or weakened the effects of genes; the biggest SCA of per character appeared in wheat combinations of YS-type thermo-sensitive wheat male sterile lines;The GCA and SCA of K-sterile line and the YS thermo-sensitive male sterile lines is relatively independent, there is no obvious relationship; There are significant differences between K-sterile line and the YS-sterile line. The thermo-sensitive male sterile line is no obvious advantages, but the yield characters on the edge with a better performance. The lowest value of SCA is in the K-sterile line. But the highest value of SCA is in the two YS- type wheat male sterile lines.2. The quantitative traits major gene and more mixed genetic model was used in the hybrid offspring of K-type male sterile lines with the 160. The results showed that: The F2 group of the K3314A×160 were controlled by two pairs of major gene and multiple genes (B-1 model), the main gene express for the additive-dominant-epistatic effects. The main genetic rate was 96.5%, that showed fertility was controlled by the major infertility gene, the less affected by the environment. On the additive effect, the express higher effect than the second main infertility gene. The first main infertility gene has higher dominant effect too. To pistatic effect, additive×dominant effect of the first major gene similar to dominant×additive effects of the second major infertility gene. That is to say, the sterility of two major infertility impacts is almost identical.3. Fertility genetic analysis on A732×160 and A3017×160 F2 groups which used the main effect quantitive characters gene and multi-genetic mixed model showed that:YS-type thermo-sensitive fertility genetic are controlled by two major genes, B-1 model is the best genetic model in the YS-thermo-sensitive male sterile lines group; To additive effect, the two YS-type male sterile lines are shown the additive effect by the first gene of fertility controled stronger than the second major genes. The dominant effect of the first fertility gene are higher than the second major geines; To pistasis effect, YS-type thermo-sensitive male sterile lines shows the same effect on the 2 major dominant effect of genes.4. Compared of fertility genetic between K-type wheat male sterile line and YS-type wheat male sterile lines shows the same result. Both of them are followed B-1 model.That is, two major genes and multi-gene model; to additive effect, the two YS-type male sterile lines are shown the additive effect by the first gene of fertility controled stronger than the second major genes. The dominant effect of the first fertility gene are higher than the second major geines; To pistasis effect, YS-type thermo-sensitive male sterile lines shows the same effect on the 2 major dominant effect of genes.But they have differences:The genetic rate of two major gene was 95.6%, 74.95% and 89.1%. It shows that the environmental impact is in different degrees. The sterility of YS-type thermo-sensitive male sterile line is controlled by the environment is greater than K-type male sterile lines.