莴笋菌核病在我省有两个危害时期,多数地区第一次受害在11—12月,第二次在翌年的3-4月。中江县10—12月及翌年2—4月受害较重,1989年9月下旬已观察到发病植株。据报道,绵阳等地莴笋菌核病的危害较重,莴笋减产达20—50％,重者达100％,其损失超过了霜霉病, Lettuce sclerotinia in our province has two hazardous period, most of the victims in the first 11-12 months, the second in the following March-April. Zhongjiang County was hardest hit in October-December of the following year and February-April of the following year, and infected plants were observed in late September 1989. It is reported that Sclerotinia sclerophylla Mianyang and other places more damaging sclerotinia, lettuce yield of 20-50%, weight of up to 100%, the loss of more than downy mildew,