2019 ASHS Annual Conference

Nuclear male sterility (NMS) is one of the most extensively exploited pollination control mechanisms for hybrid breeding in muskmelon. Five recessive and non-allelic male sterility genes, ms-1, ms-2, ms-3, ms-4 and ms-5 possessing unique phenotypes have been reported in muskmelon. An inbred MS-1 containing male sterility gene ms-1, refined at Punjab Agricultural University, Ludhiana (India) has been successfully exploited for the development of commercial F₁ hybrids. Since the transfer of a recessive gene is laborious and time-demanding, male sterility gene ms-1 could not be incorporated to develop new NMS lines. The present study was undertaken to identify codominant simple sequence repeat (SSR) marker(s) linked to ms-1 gene using an F₂ population derived from a cross ‘MS-1 × KP₄HM-15’. Total 498 SSR primers were screened between the parents followed by bulk segregant analysis (BSA). The linkage analysis of 150 F₂ plants using putative primers mapped two SSR markers, DM0187 and DM0038 linked to the ms-1 gene on chromosome 6. The marker, DM0187 was closely linked at a genetic distance of 6.6 cM while the distance between the ms-1 locus and DM0038 marker was 21.1 cM. The closely linked marker will be useful for marker-assisted selection (MAS) in muskmelon breeding programs and hybrid seed production, till more tightly linked markers are available. Further, determination of the chromosomal position of ms-1 gene will be useful for fine mapping and also provide a basis for cloning of this gene.