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近年来,随着耕作制度的改革和气候条件的变化,棉田玉米螟的危害也逐年加重。从棉花蕾期开始,一代玉米螟便开始发生为害。幼虫蛀人心叶、茎尖及叶柄、茎杆等处、造成塌叶、断杆和多头棉。严重时,棉株半边枯死或整株萎蔫,影响正常现蕾。一、发生的原因及特点棉田玉米螟以逐年加重,与食料和田间小气候有着直接的关系。首先是耕作制度的改革。本地区春玉米面积逐年急剧下降,而麦套玉米和夏玉米面积却大幅度地上升。由于越冬幼虫的虫口基数较大因而第一代玉米螟发生也较重。越冬幼虫一般在5月上旬化蛹,成虫
In recent years, with the reform of farming system and the change of climatic conditions, the damage of cotton field corn borers has also been increasing year by year. Starting from the cotton bud stage, a generation of corn borer began to harm. Larvae moths people heart leaves, shoot tips and petioles, stems and other places, resulting in collapsed leaves, broken bar and long cotton. Seriously, the cotton plants wither half or wilt, affecting the normal budding. First, the causes and characteristics Cotton borer to increase year by year, and food and field microclimate has a direct relationship. The first is the reform of farming system. The area of spring maize in the region has dropped sharply year by year, while the area of wheat maize and summer maize has risen sharply. Due to the larger population of overwintering larvae and the first generation of corn borer is also heavier. Overwintering larvae generally in early May pupation, adult