Genetic Polymorphism of 20 Sweet Sorghum Cultivars as Revealed by RAPD and SSR Markers

This study analyzed the genetic polymorphism and relationship of 20 sweet sorghum cultivars by RAPD and SSR molecular markers.The results showed that 31 polymorphism primers were obtained from the screening using RAPD marker analysis.A total of 202 bands were obtained;167 of them showed polymorphisms,with a polymorphism rate of 82.67%;the genetic similarity(GS)coefficients among the studied cultivars ranged from 0.613 to 0.870;the average genetic similarity coefficient was 0.744.A total of 297 bands were amplified from these 91 pairs of SSR primers,and 267 bands showed polymorphisms,with a polymorphism rate of 89.90%,and genetic similarity coefficients ranging from 0.555 to 0.837 among the 20 sweet sorghum varieties were obtained,and the average value was 0.695.This result displayed a similar trend with results from the 2 individual data analyses discussed above for RAPD and SSR molecular markers,with some differences.The results based on combined data could more comprehensively and objectively reflect the fundamental genetic differences among these varieties.