Reid B L, Bennett G W, Yonker J W
Department of Entomology, Purdue University, West Lafayette, Indiana 47907.
J Econ Entomol. 1990 Apr;83(2):444-50. doi: 10.1093/jee/83.2.444.
In a study examining three application rates for fenoxycarb, new interpretations of population age structure in relation to sterility levels and population reductions were used to establish important concepts in the management of German cockroaches, Blattella germanica (L.), with juvenoids. No significant differences in population reductions were noted when 0.5%, 0.25%, or 0.125% fenoxycarb was used to supplement propetamphos. However, significant differences in levels of induced sterility and in the age structure (measured as nymph-to-adult ratios) of treated populations were detected. The 0.125% rate caused lower, less consistent levels of sterility than the two higher rates, which maintained approximately 80% sterility from 4.5 mo and beyond. In addition, the 0.125% rate did not significantly reduce nymph-to-adult ratios in treated populations relative to that caused by the propetamphos alone (positive control). The two higher rates significantly reduced nymph-to-adult ratios, thereby lowering biotic potential and the capacity of a population to rebound from suppression. A relationship between the level of sterility induced by juvenoids and reductions in nymph-to-adult ratios permitted formulation of a biological action threshold for regulating treatment. This action threshold appears to be more meaningful than time intervals for scheduling retreatments in the long-term management of German cockroaches with juvenoids.
在一项研究中，研究了苯氧威的三种施用量，采用与不育水平和种群减少相关的种群年龄结构新解释，来确立使用保幼激素类似物管理德国小蠊（德国小蠊，L.）的重要概念。当使用0.5%、0.25%或0.125%的苯氧威来补充残杀威时，未观察到种群减少有显著差异。然而，在诱导不育水平和处理种群的年龄结构（以若虫与成虫比例衡量）方面检测到了显著差异。0.125%的施用量导致的不育水平低于另外两种较高施用量，且不太稳定，而另外两种较高施用量从4.5个月及以后能维持约80%的不育率。此外，相对于仅使用残杀威（阳性对照）而言，0.125%的施用量并未显著降低处理种群中的若虫与成虫比例。另外两种较高施用量显著降低了若虫与成虫比例，从而降低了生物潜能以及种群从抑制状态反弹的能力。保幼激素类似物诱导的不育水平与若虫与成虫比例降低之间的关系，使得能够制定用于调控处理的生物作用阈值。在使用保幼激素类似物对德国小蠊进行长期管理时，这个作用阈值似乎比安排再次处理的时间间隔更有意义。
