Marker-assisted selection for monoecy in chamoe (Cucumis melo L.)

The DNA marker T1ex, originally developed from melon (Cucumis melo L.) for monoecy, was employed in chamoe, which is referred to as oriental melon. This marker shows size variations in monoecious melon. However, in chamoe, no such detrimental size variation was found in monoecious chamoe, and 99% association between flower phenotypes and genotypes of the T1ex marker was observed in 106 lines of chamoe. To evaluate the efficacy of the T1ex marker for marker-assisted selection (MAS), a total of 240 plants of chamoe breeding lines were screened using the T1ex marker. Among these, 98 varieties were selected. Although the T1ex marker might not be useful for MAS in melon, we found 100% concordance between genotypes and phenotypes for sex expression in chamoe. These results suggest that the T1ex marker will be a useful resource for MAS for monoecy in chamoe.