Analysis On Genetic And Association With Agronomic Traits By Using SSR Markers In Barley (Hordeum Valgare L.)

Bariey（Hordeum vulgare L.）is the fourth largest crop in China, which is used as the mainraw material for beer industry, and it plays an important role in the development of nationaleconomy. In order to solve the problem of the narrow genetic base of parents, achievingbreakthroughs in breeding, it’s essential to achieve a suitable evaluation for introducinggermplasm resources, analysis genetic diversity of parent materials, understand the genetic basisof agronomic traits.In this research, a total of64SSR markers which distributed in whole genome were selectedfor analysis genotypes of221barley materials. A total of85SSR markers were screened forpolymorphism among113parent materials, and then the analysis on genetic diversity of thesematerials were detected. Population structure was analyzed through57selected markers, andthen association analysis between SSR markers and5agronomic trait. These studies will provideuesful information for hybridization combination of parent materials, map-based cloning relatedgenes related and molecular assisted breeding. The main results are as follows:1. A total of200alleles were found from113materials by using86SSR markers, rangedfrom1to5. Allele frequency ranged from0.0088to1.0000and Shannon index ranged from0.0000to1.2236. A total of192alleles were detected by64SSR markers on chromosomes1Hto7H in221barley accessions with2-7alleles per locus. The allelic frequency ranged from0.0090to0.9729, with the mean of0.3333. The gene diversity was from0.0528to0.7807,averagely0.4813. The polymorphism information content（PIC）value ranged from0.0514to0.7464with the mean of0.4113.2. The genetic similarity of the221materials accessions ranged from0.4844to0.9792withthe mean of0.7023. All accessions were clustered into two major groups and Genetic distancebetween the two subpopulations was0.3358.In113materials by using86SSR markers, thegenetic similarity ranged from0.5504to0.9897, with the mean of0.7477. Genetic structureanalysis showed that the population of these parent materials was composed of4subpopulations.3. Genotypes analysis of221barley materials through64SSR markers. There was linkagedisequilibrium（LD）among linked loci and unlinked loci pairs, and830out of2016loci pairs（41.2%）had significant LD（P <0.01）with D average value of0.4. The LD level of developedvariety was higher than that of landraces. Target traits of developed varieties were mainlydistributed on chromosomes2H,4H,6H, and7H. 4. Population structure of113materials were analyzed through57SSR markers. There were9SSR markers associated with plant height, spike length, awn length, grain number per spikeand Spikelet Compactness under GLM program, and the rate of explanation on the phenotype ofrelated marker ranged from0.0507to0.2766. There were6SSR markers associated with plantheight, awn length and Spikelet Compactness under MLM program, and the the rate ofexplanation on the phenotype of related marker ranged from0.0238to0.1999. These markerswere on chromosomes1H,2H,3H,4H and7H.