Abstract: 【Objective】 The objective of this study is to understand the genetic diversity of proso millet germplasm from different regions and to provide an important theoretical foundation for crossbreeding, excavating drought genes and germplasm creation for future, because of its characters, such as short growth period, bearing drought and barren land. 【Method】Genetic diversity detection was done for proso millet resources by phenotypic identification and SSR markers. Distribution of nine phenotypic traits, including plant height, main spike length, leaf length, blade width, number of main stem section, the main stem diameter, spike weight per plant, grain weight per plant and thousand kernel weight were analyzed by subordinate function. Genetic diversity analysis, correlation analysis and principal component analysis of phenotypic traits were done by software DPS7.05; comprehensive evaluation on proso millet germplasm. Good genomic DNA was extracted from young leaves of 96 proso millet germplasm resources from different areas following the CTAB method, and then were amplified by simple sequence repeat molecular markers to analyze genetic diversity and genetic structure. Separation of the amplified fragments was performed on 8% denaturing polyacrylamide gels. The gels were stained with AgNO3 for visualizing the SSR fragments. The No. of allele (A), Major allele frequency(M), Gene diversity(He), polymorphism information content(PIC) were estimated by software PowerMaker 3.25. Neighbor-joined cluster analysis was aslo carried by software PowerMaker 3.25. Population genetic structure was analyzed by software Structure 2.3.1.【Result】Through genetic diversity analysis of the nine phenotypes of proso millet, it was known that the spike weight and grain weight per plant of genetic variation were the most abundant. Phenotypic traits were more concentrated and most of which were apparently interrelated. Genetic diversity of phenotypic traits of germplasm from Shanxi was the richest. Genetic diversity of phenotypic traits was different in different provinces. Principal component analysis and comprehensive evaluation were done for 9 phenotypic traits of 96 copies of proso millet germplasm resources. Comprehensive evaluation value of Neimi No.1 was the lowest, while that of Ningmi No.15 was the highest. Genetic diversity of 96 copies of proso millet germplasm resources was detected by 19 pairs of SSR primers and 112 allelic variation genes were found. The number of alleles per locus ranged from 3 to 9 and the average was 5.9, the average major allele frequency was 0.7045, the average gene diversity index was 0.4097, and the average percentage of polymorphism information content sites was 39.2%. Genetic diversity analysis of germplasm from different regions showed a close relationship among the regions. Genetic diversity index and polymorphic information content percentage of proso millet germplasm resources in Shanxi were 0.357 and 33.01%, respectively. Experimental materials were divided into three groups by genetic structure analysis based on modules and cluster analysis based on genetic distance. Results of these two division methods have similarity. Resources in three groups were connected with geographical environment closely.【Conclusion】 Proso millet germplasm resources were analyzed systematically from aspects of phenotype and molecule. The results showed that proso millet is rich in genetic variation and has a high diversity. What’s more, genetic diversity of proso millet germplasm resources in Shanxi is the most abundant.

Key words: proso millet, comprehensive evaluation, population structure, cluster analysis, genetic diversity