论文部分内容阅读
辽宁地区棉铃虫主要发生在辽西棉区,以二一三代幼虫食害棉花嫩叶、花蕾和青铃,如发生严重,铃营脱落率高达50%以上,减产在1/3以上。除危害棉花外,还危害高粱、玉米等作物。严重发生年平均高粱穗寄生率70%以上,百穗虫数达523—1330头。由于棉铃虫主要发生在本省半干旱地区,所以其发生消长在有一定蛾量的基础上和当时的气象条件密切相关。据分析,在二代
In Liaoning Province, cotton bollworm occurs mainly in the Liaoxi cotton area, infecting cotton leaves, flower buds and green bellies with 2-3 generations of larvae. In case of serious occurrence, bollworm shedding rate is as high as over 50% and the yield is reduced by more than 1/3. In addition to endanger cotton, but also endanger the sorghum, corn and other crops. Severe occurrence of annual average sorhae parasitism rate of 70%, a hundred earworms number 523-1330 head. As the cotton bollworm occurs mainly in the semi-arid area of this province, its occurrence and decline are closely related to the prevailing meteorological conditions on the basis of a certain amount of moths. According to analysis, in the second generation