Response of Melofon Breeding Lines to Powdery Mildew, Downy Mildew, Fusarium Wilt, and Sudden Wilt. R. Cohen, Department of Vegetable Crops, ARO, Newe Ya'ar Research Center, P.O. Box 90000, Haifa 31900, Israel . Shoshanna Schreiber, and H. Nerson, Department of Vegetable Crops, ARO, Newe Ya'ar Research Center, P.O. Box 90000, Haifa 31900, Israel. Plant Dis. 79:616-619. Accepted for publication 7 February 1995. Copyright 1995 The American Phytopathological Society. DOI: 10.1094/PD-79-0616.

The responses of eight melofon (pickling melon, Cucumis melo) breeding lines to powdery mildew, downy mildew, Fusarium wilt, and sudden wilt were evaluated. No resistance to races 1 and 2 of Sphaerotheca fuliginea (powdery mildew) was found; however, all melofon lines tested except D17-5 were moderately susceptible compared with the highly susceptible melon cv. Ananas Yoqne'am and the cucumber cv. Bet Alfa. Two breeding lines, P22a and P6a-3, were relatively tolerant to Pseudoperonospora cubensis (downy mildew), exhibiting the lowest disease index in both experiments conducted. All melofon breeding lines were resistant to races 0 and 1 of Fusarium oxysporum f. sp. melonis. High susceptibility to F o. f. sp. melonis race 2 was evident, while disease severity following inoculation with race 1,2 was moderate in most lines tested. There was a wide variation among melofon breeding lines in responses to sudden wilt: line D17 was very susceptible while P6a-1 did not collapse in field trials. Overall, breed-ing lines derived from cross P6 were the most promising with respect to disease resistance

Keyword(s):