在桑蚕饲育过程中,近年来经常遇到不吐丝蚕发生,严重的达60—70％。关于不吐丝蚕发生原因,目前国内外的报导,主要有生理、病理、微量农药中毒等因素,遗传因素及环境条件的影响是通过蚕体生理变化导致不吐丝蚕发生,系属生理因素影响。为探讨发生这种不吐丝蚕的原因及预防对策,我们于1983—1986年在柳州地区各县定点调查,并在柳州地区蚕种实验室饲养32批,调查221个品批,现将试验和面上调查情况综述如下: In silkworm rearing process, in recent years do not often encounter silkworm silkworm occurs, a serious up to 60-70%. About silkworm silkworm causes, the current domestic and international reports, mainly physiological, pathological, trace pesticide poisoning and other factors, genetic factors and environmental conditions are caused by physiological changes in silkworm silkworm silkworm occurs, is a combination of physiological factors influences. In order to explore the reasons for this non-spit silkworm and preventive measures, we conducted a survey in counties in Liuzhou in 1983-1986 and 32 batches were raised in the silkworm lab in Liuzhou to investigate 221 batches. Summarize the survey on the surface as follows: