根据几年来的研究结果证明,在延边地区柞蚕软化病中,由链球菌属(Streptococcus Rosen Bach)细菌感染而引起的尤其对蚕茧生产危害很大。调查结果,软化病严重地区,其发病率可达40—60％,发病重的蚕儿当代就死亡,发病轻的蚕儿即使能营茧化蛹、下一代也继续传染。为了尽快地对本病进行防治,五年来(一九七四～一九七八年)对该菌进行了系统的研究。本文将报告其研究结果: According to the results of several years of research, it is proved that the infection caused by Streptococcus Rosen Bach bacteria in Yanbian area is particularly harmful to cocoon production. Survey results show that the incidence of serious disease in areas where the incidence of up to 40-60%, the incidence of severe cases of death of Caracal, the incidence of light even if the cocoon cocoon pupation, the next generation also continue to be infected. In order to prevent and treat the disease as soon as possible, the bacteria have been systematically studied in five years (1974 ~ 1978). This article will report on its findings: