Genetic Analysis And QTL Mapping Of White Peel In Pepper Fruit

The mature pericarp of high generation self homozygous period was green（246）and high generation self homozygous mature fruit peel was white（247）as parent,and six generation groups（P₁,P₂,F₁,B₁,B₂ and F₂）were constructed,and each single plant of the six generation genetic population in the mature period of commodity was measured by visual classification in this study.The color difference meter was used to analyze the L value and C value of the peel color of each single plant of six generations in themature period of the commodity,and the genetic rule of the peel color of the ripe fruit of the capsicum was studied by the six generation joint analysis method.At the same time,the white gene of the peel of the capsicum was entered into the mature fruit of thecapsicum by SSR molecular marker technique.Preliminary positioning.The main results are as follows:1)the heredity of the peel color of capsicum was inherited from the nucleus.The heredity of green to white in the mature period of capsicum was conformed to 2 main genes+additive dominant multiple gene model（E-3 model）;the F₂ main geneheritability of L value,C value and color class value were 40.415%,90.524%and99.395%respectively,of which F₂ was F₂ The heritability of the main gene was close to100%,and the genetic and environmental effects of multiple genes were low,indicating that the genetic selection of the white peel of Capsicum in the mature period of thecommodity could be separated from the early generation.2)the capsicum with fruit green（246）and high peel white（247）high generation self inbred and homozygous pepper were studied.418 pairs of primers were screened and 11pairs of polymorphic primers were screened.A white and green gene pool wasestablished by BSA（separation group analysis）,and 11 pairs of polymorphic primers were used to screen the mixed pool with 11 pairs of polymorphic primers.A total of 6SSRs primers in two parents and mixed gene pools were screened out,which were ES-65 and ES-187,ES-273,ES-296,ES-357 and ES-363.The linkage map was established to determine that 6 markers were located on two linkage groups,in which ES-363,ES-273 and ES-65 were located in a chain group with 5.58cM and 5.08cM,respectively,and ES-296,ES-357 and ES-187 in the same chain group,and the genetic distance was19.05cM and 15.17cM respectively.3)QTL IciMapping was used to locate 180 single color traits of F₂ population by CIMmapping method and two QTLs loci were found.Among them,there was one between ES-357 and ES-296,LOD was 5.68,phenotypic contribution rate was 7.57%,andadditive effect was 1.14.There is a QTL locus between ES-363 and ES-273,with a LOD value of 5.29,a phenotypic contribution of 10.15%,and an additive effect of 1.39.This study laid a foundation for subsequent molecular marker assisted breeding of capsicum and the inheritance of white traits in pepper peel.