论文部分内容阅读
棉铃虫是棉花的主要虫害,每年均有不同程度的发生,大发生的年份产量损失达20%以上。为了摸清棉铃虫对棉花的为害损失和比较科学地确定防治指标,为今后开展大面积防治提供科学依据,特进行了试验研究,现将试验结果整理如下:一、试验方法选择棉田一丘,面积为3分,棉铃虫三、四代各设四个处理区,三代重复一次,共计12个处理区,每区面积0.5厘,每区笼罩20株棉花,棉铃虫三、四代接种棉花百株卵量为15粒,30粒,45粒和对照不接卵作比较。小区实际接卵数量为3粒,6粒,9粒,并重复再接一次卵量。因接的卵量孵化幼虫很少,所以再接一、二龄幼虫,棉铃虫
Cotton bollworm is the main insect pest of cotton, which occurs in varying degrees every year. The annual yield loss in large occurrence is more than 20%. In order to find out the harm of cotton bollworm damage to cotton and more scientific to determine the prevention and control indicators for the future to provide a scientific basis for large-scale prevention and control, especially the pilot study, the test results are summarized as follows: First, the test method to select a cotton hill, Area of 3 points, three generations of cotton bollworm set up four treatment areas, three generations of repeat, a total of 12 treatment areas, each area of 0.5%, each covering 20 cotton, cotton bollworm three or four generations of cotton inoculation The number of ovules was 15, 30, 45 and the control did not catch eggs for comparison. District actually received an egg number of 3, 6, 9, and then repeat the egg again. Due to the small amount of eggs hatch larvae, so pick one or two instar larvae, bollworms