Research On Genetic Diversity Of The Population From The Offspring Of The Cross Of "Jinhan125×Xiye501"

In this study, taking eighty-five lines in the population from the offspring of the cross Jinhan125×Xiye501as materials tested, and twenty-two materials which are from the parents, kinship-related and wild cultivars as control, phenotypic traits and SSR markers were comprehensively analyzed for guide of selection of excellent lines in offspring populations by research of genetic diversity, and the relationship between genetic differentiation and trait variation. The results showed:1. Traits in the population from the offspring of the cross Jinhan125×Xiye501possessed abundant variation and wide ranges which meant they had high potential in selection. Significant correlation existed among many important traits which made it different to select lines with high yield, contents of oil and protein. Four principal component factors were obtained by Principal Component Analysis of agronomic traits of the population; the factors were yield factor, plant shape factor, pod shape factor, and stem shape factor. The trais including plant height,2-seed pod number,3-seed pod number, valid branch number and pod number in branches should be taken into account in selection. The lines in the population were classified into three groups by cluster analysis.2. By amplification of the mixed population made up of107materials with30pairs of30SSR primers,70allelic variations were found, the range of the allelic variation number by each marker was2-4, the range of polymorphism information content was0.196-0.551, the range of genetic diversity index was0.379-1.102, the variation range of genetic similarity of the lines was0.1667-1, and107lines were classified into6groups by cluster based on genetic distance.3. By germination tests with the seeds of107lines under the drought stress caused by PEG6000, using subordinate function to drought-resistant coefficient and classify the lines into different drought-resistant ranks,32lines with drought resistance were identified in the population from the cross Jinhan125×Xiye501. By association analysis between drought coefficient and30markers, A216of Sat₂44which was excellent allelic variation on drought resistance at the seedling stage, and it had0.0512Synergistic effect to phenotypic effect,...