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

Abstract

Chensu, a new oriental squash variety was developed by the National Horticultural Research Institute. An interspecific hybridization was made between Jecheonjaeae, the local variety of C. moschata and C. martinezii resistant to powdery mildew in 1991. The hybrids 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 sibbed and selfed 3 times from 1994 to 1997. 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, PR1-1-7-1/8-14-2-5 was selected in 1997 and then named as Chensu. 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.