Genetic diversity analysis of phenotypic traits in 40 Capsicum annuum L.germplasm resources

WANG Tongtong; GUO Zhiwei; REN Guangqian; SUN Qiang; LIU Hejuan; ZHANG Bei; CHENG Xiangjie; JIN Zhengya; REN Fusen; ZHEN Junqi; WU Tao; LI Yi

doi:10.16861/j.cnki.zggc.2024.0662

Abstract：To enhance the utilization of the collected Capsicum annuum L.germplasm resources and improve breeding ef-ficiency,genetic diversity analysis,cluster analysis,correlation analysis,and principal component analysis were carried out in this study with 23 phenotypic traits of 40 stable inbred lines.The results showed that the diversity indices of the 23 phenotypic traits varied from 0 to 1.997,of which the highest diversity index was plant width,and the coefficient of varia-tion of single fruit mass was the largest among the quantitative traits(52.92％),which indicated that the phenotypic traits of the 40 C.annuum L.germplasm resources had rich genetic diversity.The results of cluster analysis showed that the 40 C.annuum L.germplasm resources could cluster into two taxa at genetic distance 20,and the germplasm resources of tax-on Ⅱ were mostly compact plants,with elongated and thin-skinned fruits and relatively large fruit shape index,which could provide the theoretical basis for the breeding practice of the subsequent different fruit shapes and plant shapes.The results of correlation analysis showed that the correlation coefficients of 74 pairs of traits were significant or extremely significant,indicating that most of the phenotypic traits interacted with each other.The results of the principal component analysis showed that the cumulative contribution rate of the first six principal components was as high as 77.493％,which could reflect the basic characteristics of the phenotypic traits,the twelve phenotypic traits as fruit transverse diameter,fruit shape index,and fruit cross-section shape could be used as important indexes for evaluating the genetic diversity of C.annuum L.'s phenotypes and genetic improvement of C.annuum L.variety.This study provides an important theoreti-cal reference basis for the utilization and innovation of C.annuum L.germplasm resources and variety selection.