Construction of InDel marker-anchored genetic maps and identification of QTLs governing fruit quality-related traits in winter squash (Cucurbita maxima)
摘要
Winter squash (Cucurbita maxima Duchesne), renowned for its high nutritional and economic value, is extensively cultivated globally. Elucidating the genetic basis of fruit quality-related traits is of paramount importance for molecular-assisted selection and candidate gene identification. In the present investigation, two F2 populations were developed, and seven fruit quality-related traits including dry matter content (DMC), soluble solids content (SSC), fructose (FRU), glucose (GLU), sucrose (SUC), starch (STAR), and carotenoid content (CARO), were evaluated via QTL analysis in 2018 and 2022, respectively. Two genetic linkage maps were constructed using125 and 253 InDel (Insertion-Deletion) markers corresponding to 20 chromosomes. A total of twenty-two quantitative trait loci (QTLs) for all traits were detected, which were distributed across 14 loci on eleven chromosomes, accounting for 3.23 ~ 15.22% of the observed phenotypic variations (PVE). STAR and CARO were stably detected with PVE values ranging from 12.80 to 15.13%. Major-effect QTLs associated with glucose and fructose were identified in C. maxima on linkage group (LG) 10, LG14, and LG16, with PVE values spanning from 3.23 to 8.99%. This research contributes to the understanding of QTLs and potential candidate genes associated with glucose and fructose content in ripening C. maxima fruit. The InDel-based genetic map and molecular markers linked to fruit quality-related traits are expected to enhance the application of molecular-assisted selection in C. maxima breeding initiatives.