Genetic diversity and relationship analysis of pepper germplasm resources based on phenotype traits and SRAP molecular markers

Germplasm resources is important material basis for crop genetic improvement,the genetic relationship and genetic diversity study of pepper germplasms is important base of pepper genetic improvement.In this paper,the genetic relationship and genetic diversity were studied thorough the evaluation of phenotypic traits as well as sequence-related amplified polymorphism(SRAP) molecular markers,the main results were as follows: Based on the cluster analysis of fruit traits,color of leaves and other morphological traits,the pepper germplasms in the experiment were clustered into 4 groups when the index of genetic similarity is 0.69.The 4 groups are Capsicum annuum L.var.conoides,Capsicum annuum L.var.conoides bailey,Capsicum annuum L.var.longum baily and Capsicum annuum L.var.cerasiforme baily.Using 17 pairs of SRAP primers,genetic diversity and genetic relationship among 72 germplasms were studied,a total of 182 bands were acquired by PCR,about 118 of them showed diversity in length.The genetic similarity index among the 72 pepper germplasms varied from 0.56 to 0.91,and the 72 germplasms were divided into 8 groups when the genetic similarity index is 0.737.A deviation was found between the genetic diversity and genetic relationship by SRAP marker and morphological marker in this study,and a more abundance and stable genetic diversity was found by SRAP marker on the pepper germplasms,suggesting its value in the genetic diversity and genetic relationship study of crops such as peppers.