1999年气候对棉花主要害虫发生发展的影响

1999年全疆棉花早害轻至中度发生，其中南疆重于北疆。本文从气候角度分析认为：北疆初霜异常提前，不利于害虫繁殖。南疆秋季气温明显偏高，有利于增加害虫越冬基数；暖冬有利于害虫越冬；春季回寒天气多而强，对棉虫发生极为不利；夏季北疆降水偏多，不利于害虫发生，南疆气候对害虫发生较为有利。

Effect of the Climate in 1999 on Cotton Pest Occurance and Growing

The cotton pest was occured to a medial degree in Xinjiang in 1999, the situation of which in the South was severer than that in the North. Climate condition was unfavourable to pest propagation because the early frost was shifted to an earlier date in the North.On the contrast,higher temperature of the South Xinjiang during Autumn was favourable.Warm winter was favourable to pest hibernation. The cold current happened in spring was more and stronger in the North Xinjiang, which was extremely against to cotton pest occurance. The more rains of the North Xinjiang during summer checked pest occurance. The climate of South Xinjiang was favourable to pest occurance.