Detection of putative QTL regions associated with ovary traits in melon using SNP-CAPS markers

摘要

Genetic basis of melon morphology has been well-studied over the past few years. Single nucleotide polymorphisms (SNPs) based genetic markers are widely being used for QTLs and gene(s) detection. In this study, we reported genetic linkage mapping and QTLs detection of ovary-related traits in melon using whole genome resequencing and newly developed SNPs based cleaved amplified polymorphism sequence (CAPS) markers. Resequencing analysis exhibited that two distinct parental lines of melon covered 97.48% and 96.02% of reference genome, and total 302,684 major SNPs yielded 3519 CAPS loci. An F-2 mapping population of 156 individuals was genotyped for genetic linkage mapping with novel 149 SNP-CAPS markers, and spanning total 4072 cM distance and 27.32 cM in average b/w adjacent markers on 12 chromosomes. In total, 7 detected QTLs on different chromosomes (1, 5, 7, 8 and 11) explained 4.10%-17.78% phenotypic variations for 5 ovary-related traits and QTL region for ovary hairs density on chromosome 7 is mapped first time in this study. The detected QTLs regions revealed total 134 genes at different narrow genomic regions (365.28 (OVL), 343.89 (OVW), 23.47 (OVS), 107.05 (OVHD) and 597.09 (OVHL)) in kbp b/w adjacent CAPS markers on various chromosomes. Normal distribution frequency and highly significant correlation was also noticed in phenotypic analysis. Our results provide the theoretical basis of multiple QTL insights for ovary-related traits in melon and could be further investigated in unexplored botanical groups of melon by cloning and functional characterization in future studies.