一、发生情况 棉铃虫为我省主要棉虫之一,过去为害较轻,自1970年以来,特别是1972年,发生期提早,发生量加大,为害期长,为害严重,为历年所少见。 棉铃虫在我省一般发生5代;少数地区有不完全第6代发生,但成虫发生后,不能继续繁殖。每年以第3—4代为害严重。 我国已知的棉铃虫寄主有200多种。据 First, the occurrence of Helicoverpa armigera is one of the main cotton insects in our province, the past less harmful, since 1970, especially in 1972, the occurrence of earlier, the occurrence of increased, long-term damage, serious damage, rare for many years . Cotton bollworm occurs in our province for 5 generations in general; in a few areas there is an incomplete 6th generation, but after the adult occurs, it can not continue to multiply. The third to fourth generations of serious damage each year. More than 200 host species of cotton bollworm are known in our country. according to