The insecticidal effect of the neonicotinoid insecticide thiamethoxam, applied in layers of wheat, was studied in laboratory experiments, for the control of the lesser grain borer, Rhyzopertha dominica (F.) and the rice weevil Sitophilus oryzae (L.). In general, the increase of the size of the treated layer of wheat increased parental morality and decreased progeny production for both species. However, progeny production could not be totally avoided, even when the entire grain quantity was treated. Parental morality was lower for R. dominica than for S. oryzae, but the reverse was observed for progeny production for all treatments. Insect placement drastically affected thiamethoxam efficacy, since morality was generally higher when insects were forced to move downwards from the upper layer, as compared with insects that had been placed in the bottom part of the wheat column. Our study shows that thiamethoxam can reduce insect populations in partially treated wheat, at concentrations that are comparable with other, currently registered grain protectants.

在室内实验中研究了将新烟碱类杀虫剂噻虫嗪的杀虫效果，该杀虫剂用于控制小麦小bore，Rhyzopertha dominica（F.）和水稻象鼻虫Sitophilus oryzae（L.）。通常，两种小麦的处理层厚度的增加都增加了亲代道德，并降低了后代的产量。但是，即使处理了全部谷物，也不能完全避免后代的生产。亲本道德较低为R.蠹比米象，但在所有处理中观察到后代产生的情况相反。放置昆虫会严重影响噻虫嗪的功效，因为与放置在小麦柱下部的昆虫相比，当强迫昆虫从上层向下移动时，其道德通常更高。我们的研究表明，噻虫嗪可以减少部分处理过的小麦中的昆虫种群，其浓度可与目前已注册的其他谷物保护剂相媲美。