Phenotypic Traits And SSR Genetic Diversity Of Hunan Local Rice Varieties

In recent years,as a result of industrialization and urban-rural integration process to speed up the change and agricultural planting structure,the loss of local varieties is extremely serious.At the same time,the genetic basis of China's main rice varieties has been narrowed,and breeders have realized that it is necessary to make full use of the large amount of local rice resources in China.Rich genetic diversity and widening the genetic background of breeding parents can make new breakthroughs in rice yield.Due to the large number of local rice varieties,named arbitrarily,sources collection widely and other reasons,there are too many redundancy varieties affected the research,evaluation and utilization in rice germplasm resources.In this study,a total of 218 rice varieties collected in the third census of Hunan province in 2015-2016 years were used as experimental materials to carry out comprehensive analysis of phenotypic traits and to study the genetic similarity between the local rice resources in Hunan Genebank and the same species in the survey collection resources by using SSR molecular markers.The main conclusions are as follows:(1)This study compares the near-name varieties of Hunan local rice that were kept by the farmers and preserved in the genebank.The study found that except for the E group,all the other groups had the allele variances kept by the farmer less than the alleles stored in the genebank.Genetic variation;compare the mean genetic similarity coefficient of SSR markers in the same-name group.Except for groups C and E,the materials preserved by the households> materials preserved in the genebank> materials preserved by the farmers and materials preserved in the genebank.(2)In this study,the average value of the 14 quantitative traits in rice resources in Hunan was clustered.Based on the chi-square distance of 2.024 as the threshold,218 rice germplasm resources could be divided into 7 categories.There are high-yield type and dwarf spikelet types;grain slim,large panicle type,large ear and small grain type,from which 32 rice germplasms are screened out as excellent resources for future breeding.(3)comparing the coefficient of variation of 14 quantitative traits of 57 rice resources collected from 2016 and 2017,we can find that the number of spikes,the total number of panicles,the ratio of grain length to width,and the effective panicle of single plant,the variation of the 4 expressive traits are larger among the varieties,andthe weight of 1000 grain,the length of the panicle and the whole life of the 4characteristics.The variation of the 4 phenotypic traits between cultivars was relatively stable.(4)The results of the annual variance analysis in this study show that the differences between the 14 traits among varieties and between varieties and years have reached extremely significant levels.The interannual differences existed only among the five traits of the whole growth period,the total number of panicles,the number of panicles,the ratio of grain length to width,and the length of grains.There were no significant differences among the other 9 traits during the interannual period.