Description:
Originated from a cross of breeding line PMR 70022 with a papaya ringspot virus-resistant selection of PI 180280 (Bohn et al., 1980). PMR 70022 was an F2 from a cross of PI 124111 x Crenshaw. PMR 29 was used as the backcross parent for five successive generations. PMR 29 was resistant to Podosphaera xanthi (= S. fuliginea) race 2. The material was then subjected to five generations of mass selection, two generations of inbreeding (sib- and self-pollination), and another eight generations of mass selection. The deposited seed is a bulk of six sib-pollinated plants from a previous sib-pollinated increase of the material released in 1980.
WMR 29 is resistant to papaya ringspot virus (PRSV, syn. watermelon mosaic virus 1), tolerant to watermelon mosaic virus (syn. watermelon mosaic virus 2) and sulfur tolerant. It appears to have complex resistance to powdery mildew incited by P. xanthi: uniformly resistant to strains of race 1, segregated for resistance to two strains of race 2 (2US and 2S) but was uniformly resistant to other strains of race 2 (2F and 2Z), and exhibited resistance to races N1, N2, N3, N4 and H (McCreight, 2006). The complex powdery mildew resistance may be from a combination of powdery mildew resistance genes from both parents.
Fruit of this line are heavily netted, nearly globular, have prominent net-free vein tracts (Davis, 1970), very firm flesh at full-slip (abscission). Flesh color is deep orange. Soluble solids ranged 10 to 17 %.
Bohn, G.W., A.N. Kishaba, and J.D. McCreight. 1980. WMR 29 muskmelon breeding line. HortScience 15:539–540.
Davis, R.M. 1970. Vein tracts not sutures in cantaloupe. HortScience 5:86.
McCreight, J.D. 2006. Melon–powdery mildew interactions reveal variation in melon cultigens and Podosphaera xanthii races 1 and 2. Journal of the American Society for Horticultural Science 131:59–65.