QTLs Analysis Of Melon Flesh Sourness Related Traits

As an important fruit type vegetable,melon plays an important role in the fruit and vegetable production and consumption in China.With the increasing consumption levels,the requirement of fruit and vegetable quality is also improving.The consumer choic e and market demand for breeders is no longer simple as it used to be,instead more emphasis is now being placed on quality trait breeding.As the main seasonal fruit in summer,good looking,nutrient-rich melon with sour and sweet flavor melon is now becoming the choice on the market.Therefore,the study of sour gene of melon flesh is beneficial to the breeding of flavor melon,and also provides data support for quality trait breeding.With the advent of sequencing technology,some rapid gene identification methods have gained popularity,and the time required for research has been greatly shortened.In this study,F_2:3 generation was constructed by self-pollinating the resultant F₂ generation from a cross between the melon line MR-1 which have sour flesh as the female parent and M1-15 which have non-sour flesh as male parent.The correlation of fruit traits of melon was analyzed in order to find out the potential relationship between melon flesh sourness related traits.The major loci regulating the sour gene of melon flesh was detected by bulked segregant analysis?BSA?.Based on the high-throughput sequencing results of parent materials,the SNP-CAPS primers were developed in the candidate genome region and QTLs related to the flesh sourness were detected by the genetic linkage mapping.The main findings are as follows:?1?Through the analysis of the correlation of melon flesh traits,it was found that the flesh sourness negatively correlated significantly with the flesh pH.?2?The constructed genetic linkage map which included 15 pairs of SNP-CAPS primers covered 2 linkage groups with a total distance of 140.45 c M,the average distance between the markers was 9.36 c M.?3?Through combined genotyping methods of BSA and SNP-CAPS,total of 2 main effect QTL of melon flesh sourness related traits?qph8.1,qfs8.1?with contribution rate of 23.2%,18.33% respectively were located in Chromosome 8.