Research On Application Of Soybean Stay-green Mutant In Radiation Mutation Breeding

In order to breed new soybean cultivars with high yield and excellent quality,create new germplasm,effect of radiation mutation on soybean stay-green mutant was analyzed, characteristics of genetic variation of mutation offspring of stay-green mutant in the process of mutation was further expounded, all of these could provide reference foundation for application of soybean stay-green mutant in radiation mutation breeding. In this study, the ray of 60Co-y was used to treat soybean stay-green mutant, field observation and statistics record of 89 materials of the mutation offspring and the stay-green mutant were conducted, analysis such as correlation, principal component, and cluster was carried out, and 19 main agronomic traits of the materials tested were analyzed and probed. Simultaneously,70 SSR markers were utilized for PCR amplification and detection of genetic diversity of 89 materials, and 34 markers with polymorphism were selected for analysis of genetic variation of offspring was preceded. The results showed:1. After radiation mutation, yield per plant of offspring obviously increased, stay-green nature weakened, but there is also a rare mutation offspring to a better direction. So, it is hard to accomplish for the research material to keep high yield and stay-green nature simultaneously.2. By morphological observation, variation to different degrees of leaf shape, flower color, and fertility occurred.3. By correlation analysis of agronomic traits of offspring, correlational and restrictive relation among the traits were obtained.5 principal components were gained by dimensionality reduction for 17 traits by PCA. The five components were yield factor, pod number factor, stem shape factor, plant shape factor, and pest factor. Also, the materials tested were classified into four groups such as low-yield, medium-yield, high-yield, and extremely-high-yield by cluster analysis.4. By analysis of genetic diversity of 89 materials using 34 SSR primers,96 allelic variations were detected, the range of allelic variations in different sites were 2-5, averagely,2.8. The range of the change of polymorphism information content (PIC) was 0.049-0.693, average PIC was 0.362. The range of Shannon’s Index of SSR markers was 0.1157-1.4128, averagely,0.6998.89 materials were classified into 6 groups by cluster according to calculation of genetic distance.