The Genetic Differentiation Research On Wild Soybean Populations Of The Yellow River Delta

Wild soybean(Glycine soja),is the only one that can be hybridized with cultivation soybeans.In recent years,researchers have applied many molecular marker techniques to the study of genetic diversity.In this study,13 populations of wild soybean were elected for genetic differentiation study and their germplasms were collected from region of the Yellow River Delta region.In this study,EST-SSR was used to reveal the genetic structure and differentiation of wild soybean in the Yellow River Delta region.Our research discovered the Yellow River Delta region of wild soybean genetic diversity level and associated the variation of genetic distance and the geographic distance.Our study also provides a molecular basis for the wild soybean's further protection and rational utilization.In this study,the EST sequence from NCBI database was used to analyze the SSR markers,and 6 pairs of EST-SSR primers were designed to apply in genetic diversity analysis of wild soybean in Yellow river delta.The results showed that there were 654 SSR sites collected from 18808 ESTs of wild soybean,the SSR frequency was 3.48%.Trinucleotide repeat type was the major repeats and accounted for 46.5% of all EST-SSR types.After PCR amplification,there were 78 amplified products and 6 pairs of primers with polymorphisms.with.The average numbers of polymorphic loci per primer pair were 4.3.In this study,the genetic diversity of wild soybean in the Yellow River Delta region was revealed by four indicators.The four indicators were the number of effective alleles(Ne),Shannon diversity index(I),the proportion of polymorphic loci(P),and the number of alleles(Na).In the EST-SSR analysis,the average values of them were 2.6281,1.0526,82.80%,and 3.80.The results showed that the genetic diversity of wild soybean populations was higher in the Yellow River Delta region.Studies on the genetic variation and structure of different wild soybean populations,the Gst value is 0.2725,the Nm value was 0.6673,AMOVA showed that 87.89% of the variation in populations from inside.All the results shows that a certain genetic differentiation had occurred among thirteen populations and genetic variation mainly existed within populations,and the gene exchange between the populations was not frequently.In the UPGMA analysis of the study,Dongying and Wudi region was clustered together,and the region of Binzhou and Gaoqing were clustered together,finally the two branches and population clustered together in Jinan,Shouguang.This is probably relates to its geographical position and living environment.Using the Mantel test to describe the relationship between the genetic distance and geographical distance of each populations.The results showed that the geographical position and genetic variation among different soybean populations were significantly correlated with genetic variation(r = 0.5864,P <0.01).The conclusion was proved that the geographical location of wild soybean in the Yellow River Delta is the main factor affecting the genetic diversity and genetic differentiation.