A New Oriental Squash (Cucurbita moschata) Cultivar, ＂Mansu＂ Resistant to Powdery Mildew

Abstract

Mansu, a new oriental squash variety was developed by the National Horticultural Research Institute. An interspecific hybridization was made between Jecheonjaerae, the local variety of Cucurbita moschata and C. martinezii resistant to powdery mildew in 1991. The hybrid was backcrossed to Jecheonjaerae in 1992. Progenies which were selected on the basis of high resistance to powdery mildew and non-bitterness of immature fruits from the BC1F1 population, were again backcrossed to Jecheonjaerae. The powdery mildew-resistant and non-bitter individuals which were selected from the BC2F1 population, were selfed 2 times, again backcrossed to Jecheonjaerae, and then selfed 3 times in 1993 to 1998. For selection of each progeny which were highly resistant to the powdery mildew, both the young and the adult plants were tested. Among the advanced lines, PR1-1-3-9-7-3-3-10-11 was selected in 1998 and then named as Mansu. It showed slightly lower tolerance to powdery mildew than that of C. martinezii, but its fruit quality was similar to that of the maternal parent, C. moschata.