Inheritance and linkage analysis of resistance to zucchini yellow mosaic virus, watermelon mosaic virus, papaya ringspot virus and powdery mildew in melon

A melon (Cucumis melo L.) breeding line derived from PI 414723 is resistant to three potyviruses, watermelon mosaic virus (WMV), zucchini yellow mosai c virus (ZYMV), papaya ringspot virus (PRSV), and to powdery mildew (PM). T he inheritance and linkage relationships of these four resistances were stu died in a segregating F2 population and derived F3 families from a cross be tween cultivar Top Mark and the resistant breeding line. Dominant monogenic inheritance of all four resistances was observed. We report that line 4147 23-4S3, which was initially selected as a source of ZYMV and WMV resistance , is also a source of dominant monogenic resistances to PRSV and PM race 1. We also report on genetic linkage (significant departure from independent segregation, chi (2) =58.1, p much less than 0.0001) between resistance to WMV and ZYMV. The map distance between these loci was estimated to be 7.5 c m. The genes for resistance to PM and PRSV segregated independently from ea ch other, and from ZYMV and WMV resistance.