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作者用一种衡量蚜虫危害的新尺度——“累计蚜量(头/天)”,对油菜不同生育阶段的单株损失及补偿作用分别作了研究。结果表明:油菜苗期、苔花期、荚果期都存在着一个造成损失的临界危害量(C)。苗期 C 为360～440(头/天),苔花期 C 为13500～16500(头/天),荚果期 C 为2700～3300(头/天)。危害量与损失率的关系符合 logistic 曲线。根据研究结果提出“有害株”的概念,既有蚜虫而又影响产量的植株。并结合蚜虫消长规律及累计蚜量的计算原理推导出确定“有害株”蚜量标准的公式B=C/(1/2)T(1+Q~n)+ITQ(1-Q~(n-1))/(1-Q)经比较,认为“危害株率”是蚜虫防治指标理想的尺度,它不仅明确可靠,而且简单易行。
Using a new measure of aphid infestation - “cumulative aphids (head / day)”, the authors studied separately the individual plant losses and compensatory effects at different growth stages of rape. The results showed that there was a critical damage amount (C) at the seedling stage, the moss flowering stage and the pod stage. The seedling C was 360-440 (head / day), the flowering period C was 13500-16500 (head / day), and the pod C was 2700-3300 (head / day). The relationship between the amount of damage and the loss rate is in accordance with the logistic curve. According to the results of the study, the concept of “harmful strain” was put forward, and the plants which had both aphids and yield were affected. According to the rule of the growth and decline of aphids and the calculation principle of accumulated aphids, the formula B = C / (1/2) T (1 + Q ~ n) + ITQ (1-Q ~ -1)) / (1-Q). It is considered that the rate of “harmful strain” is an ideal index for controlling aphids, which is not only reliable but also simple and easy.