Description:
Originated from a cross of ‘PMR 45’ with melon aphid (Aphis gossypii) resistant parent 90234, a self-pollinated derivative of PI 371795 (McCreight et al., 1992). The released line was from a mass increase of three bulked F6 progenies from the 9th backcross generation. ‘Hale’s Best Jumbo’, a large-fruited selection of ‘Hale’s Best’ (Whitaker and Davis, 1962) was used as the backcross parent for the last four backcrosses. It exhibited high-level resistance to melon aphid and, like ‘Hale’s Best Jumbo’, was susceptible to powdery mildew incited by Podosphaera xanthi (= S. fuliginea) races 1 and 2 in California at the time of its release in 1984. The deposited seed was derived from two successive bulked, sib-pollinated increases of the material released in 1984.
Reported resistances of AR Hale’s Best Jumbo to P. xanthi races 2F and 5 may have been derived from PI 371795, based on the observations of resistance to these two races exhibited by PI 414723, which was derived from PI 371795 (McCreight et al., 1992). It should be noted that ‘PMR 5’ is also resistant to these two races and was the backcross parent for two generations prior to the four successive backcrosses to ‘Hale’s best Jumbo’ (McCreight et al., 1984). AR Hale’s Best Jumbo only moderately resembles ‘Hale's Best Jumbo’. The fruit are round-oblate, deeply ribbed, and heavily netted, but with net-free vein tracts (Davis, 1970). The flesh is thin and salmon-orange in color. The seed cavity is large. AR Hale's Best Jumbo has a drier seed cavity and firmer flesh than ‘Hale’s Best Jumbo’ which is soft compared with ‘PMR 45’. Soluble solids ranged between 12 % and 16 %.
Literature Cited
Davis, R.M. 1970. Vein tracts not sutures in cantaloupe. HortScience 5:86.
McCreight, J.D., G.W. Bohn, and A.N. Kishaba. 1992. ‘Pedigree’ of PI 414723 melon. Cucurbit Genetics Cooperative Report 15:51–52.
McCreight, J.D., A.N. Kishaba, and G.W. Bohn. 1984. AR Hale's Best Jumbo, AR 5, and AR Topmark, melon aphid-resistant muskmelon breeding lines. HortScience 19:309–310.
Whitaker, T.W. and G.N. Davis. 1962. Cucurbits: botany, cultivation and utilization. Interscience, N.Y.