SSR Analysis Of The Genetic Diversity Of Maize Germplasm Resources In Northeast China

The analysis of genetic diversity of maize germplasm resources can verify the kinship relationship and genetic diversity distribution between maize,and provide a theoretical basis for the study of parental selection and taxonomic status of maize in maize breeding.It provides reference for the collection,preservation,identification,rational utilization and germplasm innovation of maize germplasm resources.In this study,morphological markers and molecular marker techniques were used to analyze the genetic diversity of 149 maize germplasm resources in Northeast China,and the results were as follows:The average coefficient of variation of the four quality traits of 149 inbred lines of maize was 11.76%,and the variation of the coefficient of variation was 3.44%～18.28%,among which the coefficient of variation of fiber content was the smallest,the coefficient of variation of oil content was the largest,and the coefficient of variation of100-grain weight traits was 17.4%.The correlation analysis of the five personality traits of protein,oil,fiber,starch and 100 grain weight showed a significant positive correlation between oil and protein,and there was also a correlation between starch and oil and protein.SPSSv25.0 software was used to systematically cluster 149 inbred lines according to quality shape,and 149 inbred lines were divided into ten groups.From 80 pairs of SSR primers,20 pairs of primers with good polymorphism and stable bands were screened.A total of 89 allele loci were detected in 149 inbred lines in 20 pairs of primers,with an average of 4.46 alleles detected per pair of primers,and2～10 allele loci(Na)detected in each pair of SSR primers.The average value of the Shannon Information Index(I)is 0.64,the minimum value is 0.22,and the maximum value is 0.9;the average value of the expected degree is 0.64,the minimum value is0.22,and the maximum value is 0.94.The average value of the polymorphic information volume(PIC)is 0.54,the maximum value is 0.86,and the minimum value is 0.22.The genetic similarity coefficient of 49 maize inbred lines was between 0.31～0.89,the average genetic similarity coefficient was 0.58,W217 and W219 had the largest genetic similarity coefficient,and the closest relatives;W001 and W476 had the smallest genetic similarity coefficient and the farthest relative.The results of SSR molecular marker UPGMA cluster analysis divided 149 maize into 5 taxa and 8subgroups.The results of genetic structure analysis divided 149 maize germplasm into three groups,which were consistent with the SSR marker clustering resultsThe results of SSR molecular marker clustering and quality trait marker clustering were compared,and it was found that there were differences between the two,which may be related to environmental factors.It was explained that phenotype and genotype should be studied together in the study of genetic diversity of maize germplasm resources.