Studies on the Breeding of the Resistant Varieties to Fusarium-Wilt of Sponge Gourd, Luffa cylilrdrica, Roem. II On the Development by Direct Seleqtion in the Wilt-infested Field.

Abstract

The authors are cairrying on a series of breeding work aiming the resistant varieties to wilt of sponge gourd, caused by a fcrma of vascuiar Fusaria, using a lot of wilt-infested fields in the center of the infested area. Hamana County. Shizuoka Prefecture. In the first paper we have already reported about the breeding by polyploidy. Although Daruma, a leading variety for flbernet use, was recognized as a susceptible' one, in our investigation, there found frequently, some survived individuals in some heavily infested fields. Then, the selection method in this papdr was perfbrmed to find out whether we could obtain resistant lines directly from a variety by means of selecting such survived individuals in a infested field; without applying: hybridization. The effect of t, his selection was far better than our expectation, so that we repoft this result in this secorid paper.