Analysis Of Genetic Diversity Of Wheat Landraces From Yangtze River Valley By SSR Markers

In order to broaden the genetic base of wheat varieties, explore excellent genetic resources, and understand the genetic diversity of wheat landraces, specific SSR markers were used to characterize wheat landraces in the upper reaches of the Yangtze River Basin.Genetic diversity of343wheat landraces in the upper reaches of the Yangtze River Basin were genotyped using56SSR primers, the results showed that the56of SSR loci detected254alleles, the number of alleles per locus ranged from2to13, with average of4.54alleles per locus. Polymorphic information content was0.043-0.896, with an average of0.555. The genetic similarity coefficient (GS) among the landraces ranged from0.432to1.000, with the average of0.837, indicating high SSR diversity in wheat landraces from the upper reaches of the Yangtze River Basin.Of the56loci,20,19and17were sampled from A, B and D genome, respectively. Total of100alleles were detected by20loci from a genome, with an average of5.00allele per locus and the average PIC of0.564;88alleleswere revealed by19loci on B genome, with an average of4.63allele per locus and the average PIC of0.599;66alleles were detected by the17loci on D genome, with an average of3.88allele per locus and the PIC average of0.494. The average number of allele was A genome> D genome> B genome, but PIC was B genome> A genome> D genome, the highest genetic diversity (5.18) was detected on homology group of1, while the lowest one (3.88) was found on homology group of5. The average number of alleles on each homologous group was homology group1> homologous group4>homogenous group7> homologous group3> homologous group2> homologous group6> homologous group5. The highest PIC (0.623) was detected on homology group4, the lowest PIC (0.478) was found from homology group5homologous group4> homologous group3=homogenous group7> homologous group2> homologous group1> homologous group6> homologous group5. In21chromosomes, chromosome group4A has the highest average number of alleles (7.00) and second highest average PIC (0.600) among the A genome group,4B has the highest average number of alleles (7.50) and average PIC (0.797) among the B genome group,1D has the highest average number of alleles (5.25) andthe third highest average PIC (0.540) among the D genome group. The polymorphic information content of5D is lowest, only0.308. Overall,4B has the highest genetic diversity, and5D has the lowest genetic diversity.The correlations between SSR markers and the eight agronomic traits, four quality traits and six resistance properties were analyzed. Spearman correlation analysis results showed that correlation between genetic diversity based on SSR markers and morphological phenotype was not significant (r=0.185, P=0.185).