QTL Analysis of Traits Related to Melon Stigma and Ovary Size

The melon varieties MR-1 and M4-7 were used as the parent materials to produce hybrids. A total of 170 F₂ individuals were used as the mapping population to construct a genetic linkage map. In this study, 240 cleaved amplified polymorphism sequence（CAPS） molecular markers were developed, and 105 of which showed polymorphism between parents. The map contained 105 markers grouped into 12 linkage groups, spanning a total length of 1 998.85 cM, with an average length of 19.04 cM between markers. The composite interval mapping（CIM） method was used to detect QTLs related with melon stigma and ovary traits: stigma longitudinal diameter（STLD）, stigma transverse diameter（STTD）, stigma weight（STW）, ovary longitudinal diameter（OLD）, and ovary transverse diameter（OTD）. A total of nine QTLs were identified: six for stigma size and three for ovary size. A total of six loci were detected for stigma size, which included two loci for stigma longitudinal diameter, two loci for stigma transverse diameter, and two loci for stigma weight. The major effective locus regulating stigma transverse diameter was qSTTD-9-1. A total of three loci were identified for ovary size traits, including one locus for ovary longitudinal diameter and two loci for ovary transverse diameter.