Reid B L, Bennett G W
Department of Entomology, Purdue University, West Lafayette, IN 47907.
J Econ Entomol. 1994 Dec;87(6):1537-46. doi: 10.1093/jee/87.6.1537.
The influence of sterilization by hydroprene on population dynamics in the German cockroach, Blattella germanica (L.), was studied in the laboratory where more detailed and accurate assessments could be achieved than would be possible under typical field situations. The gradual accumulation of sterile adultoids (i.e., adults with twisted wings, indicating exposure to hydroprene) during treatment, or their decreasing abundance after treatment, produced distinctive patterns in the dynamics of treated populations. The percentage of gravid females (a reproductive index) was first to respond to treatments, because increases (or decreases) in the percentage of gravid females preceded reductions (or recoveries) in sample density and nymph-to-adult ratios by 4-6 wk. Trends in the percentage of adultoids were negatively correlated with the percentage of gravid females and indirectly measure the activity of hydroprene. Initial reductions in the percentage of gravid females, sample density, and nymph-to-adult ratios began at or about the time when approximately 80% of adults had twisted wings (i.e., were adultoids). As the percentage of adultoids attained (or declined below) the 80% level, we can accurately predict the subsequent decline (or recovery) in nymph-to-adult ratios and, thus, sample density. These data support a proposal to adopt the 80% level of adultoids as an action threshold for regulating juvenoid treatments to maximize population suppression. The role of this action threshold in the long-term management of chronic B. germanica infestations or insecticide resistant populations is discussed.
在实验室中研究了烯虫酯绝育对德国小蠊（Blattella germanica (L.)）种群动态的影响，相较于典型的野外情况，在实验室里能够实现更详细、准确的评估。处理过程中不育成虫（即翅膀扭曲的成虫，表明接触过烯虫酯）逐渐积累，或者处理后其数量减少，这在处理种群的动态中产生了独特的模式。怀孕雌虫的比例（一种繁殖指标）最先对处理做出反应，因为怀孕雌虫比例的增加（或减少）比样本密度和若虫与成虫比例的降低（或恢复）提前4至6周。不育成虫的比例趋势与怀孕雌虫的比例呈负相关，并间接衡量了烯虫酯的活性。怀孕雌虫比例、样本密度和若虫与成虫比例的最初降低大约始于约80%的成虫翅膀扭曲（即成为不育成虫）之时。当不育成虫的比例达到（或降至）80%的水平时，我们可以准确预测随后若虫与成虫比例以及样本密度的下降（或恢复）。这些数据支持一项提议，即采用80%的不育成虫水平作为调节保幼激素类似物处理的行动阈值，以最大限度地抑制种群数量。本文还讨论了该行动阈值在德国小蠊长期慢性侵扰或抗杀虫剂种群管理中的作用。
