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随着杂交优势的利用,玉米种植面积不断扩大,成为旱作地区的主要粮食作物。笔者在实际工作中发现,玉米穗期害虫种类多,为害逐年加重,为了解本地区穗期害虫发生种类及发生动态,笔者于1989年对此进行了系统的调查研究,现将结果报道如下:内容及方法1.玉米穗期害虫种类调查:在春玉米灌浆初中期、夏玉米灌浆初中期和夏玉米灌浆中后期,按本市四个自然片,进行三次大田普查,每次普查50块田,记数穗期害虫种类及发生量。
With the utilization of hybrid advantages, corn acreage has been expanding and becoming a major food crop in dryland areas. The author found in the actual work, corn ear variety of pests, pests increased year by year, in order to understand the occurrence of pests in the region the type and occurrence of dynamic, the author conducted a systematic investigation of this in 1989, the results are reported as follows: Content and methods 1. Corn ear pest species survey: In the early spring corn filling medium, early summer corn filling and summer maize filling middle and late, according to the city’s four natural films, three field surveys, each census 50 fields , Count the number and occurrence of spikes pests.