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本文述及棉铃虫为害特性及其与为害后棉株的补偿作用关系。根据棉株生命表资料,蕾期棉株蕾花的脱落主要系由棉铃虫为害所致。而铃期蕾铃的脱落,则主要系由棉株的生理条件。在蕾期,前三周内蕾花被害脱落后,棉株的补偿作用是很高的,从第四周起补偿作用逐渐下降,而到铃期阶段时补偿作用降至很低水平。因此蕾期棉株遭受一定数量以内的棉铃虫为害,而使蕾花脱落后,反而可促使棉花增产。根据棉铃虫生命表资料,从卵期至三龄末幼虫期的累计死亡率占总死亡率的90％以上,结合幼虫死亡率与不同龄期为害水平分析,棉铃虫对棉株的主要为害阶段系在2—3龄期,其对果实的为害量占总为害的65％。而棉株被害蕾铃的田间空间分布型系遵从负二项分布,期公共K值为3.4626。
This article deals with the damage characteristics of cotton bollworm and its relationship with the compensatory effect of the damaged cotton plants. According to the life table data of cotton plants, the buds of buds of buds in budding stage are mainly caused by the damage of cotton bollworm. The bell-ring buds fall off, then mainly by the cotton plant physiological conditions. In the bud stage, the first three weeks after the flower buds fall off, the compensation effect of cotton plants is very high, from the fourth week compensation gradually decreased, and to the bell stage compensatory effect dropped to very low levels. Therefore, bud cotton plant suffered a certain number of cotton bollworm damage, leaving bud flower shedding, but can promote cotton yield. According to the life table of cotton bollworm, the cumulative mortality from the egg stage to the end of the third instar larvae accounted for more than 90% of the total mortality. Combined with the mortality of larvae and the analysis of the damage levels at different stages, the main damage stage of cotton bollworm to cotton plants Department in the 2-3 age, its damage to the fruit of the total damage accounted for 65%. The field distribution of cotton bollworm was followed by negative binomial distribution, with a public K value of 3.4626.