论文部分内容阅读
粟秆蝇是谷子的主要害虫。近年来在北方谷子产区,随着耕作制度的变动,夏播谷的扩大,以及间、套种和不同播期等,使谷子易受害的拔节和孕穗生育阶段与幼虫发生盛期相吻合的机会增多;加上六、七月份进入雨季,田间湿度较大,适于成虫羽化、卵孵化以及幼虫取食活动。使虫源扩大,存活率高,种群数量累积增长。一般年份谷子被害率(枯心、畸形穗、白穗)达20—40％,严重年份可高达70—80％,局部地块甚至绝收。
Corn stalk flies are the major pests of the millet. In recent years, with the change of tillage system, the expansion of summer planting valleys and the intercropping, interplanting and different sowing dates in the northern millet producing areas, the chances of millet susceptible jointing and booting stages coincided with the occurrence of larvae increased ; Plus June and July into the rainy season, the field humidity, suitable for adult emergence, egg hatching and larval feeding activities. To expand the source of insects, high survival rate, the cumulative increase in the number of populations. The average annual incidence of millet (withered, deformity spike, white spike) of 20-40%, severe years can be as high as 70-80%, even partial land lot.