三化螟是上海郊区水稻的主要害虫之一。近几年来,随着郊区农业改制,三化螟的危害,也出现了一些新特点。一、全年发生量显著增加。三化螟只危害水稻,发展双季稻后,三化螟的食源较为广阔,全年发生量便随之增加。青浦县白鹤公社电灯诱蛾量,一九六四年为754只,一九六六年为1914只,一九六八年为7342只,一九七○年为11,928只,一九七一年为 Borer is one of the main pests of rice in the suburbs of Shanghai. In recent years, with the restructuring of the suburbs of agriculture, the damage of the three borer, there have been some new features. First, the annual occurrence of a significant increase. Borer borer only endangers rice, the development of double cropping rice, the stem borer food is more extensive, the annual amount will be increased. In Qingtu County Crane Company, there were 754 electric light traps in 1964, 1914 in 1966, 7342 in 1968, 11,928 in 1970, and 1914 in 1961 for