Agri-Science Queensland, Department of Agriculture, Fisheries and Forestry, EcoSciences Precinct, Brisbane, Queensland, Australia.
PLoS One. 2012;7(12):e53356. doi: 10.1371/journal.pone.0053356. Epub 2012 Dec 31.
The red flour beetle is a cosmopolitan pest of stored grain and stored grain products. The pest has developed resistance to phosphine, the primary chemical used for its control. The reproductive output of survivors from a phosphine treatment is an important element of resistance development but experimental data are lacking. We exposed mated resistant female beetles to 0.135 mg/L of phosphine for 48 h at 25 °C. Following one week of recovery we provided two non-exposed males to half of the phosphine exposed females and to half of the non-exposed control females. Females that had been exposed produced significantly fewer offspring than non-exposed females. Females that remained isolated produced significantly fewer offspring than both exposed females with access to males and non-exposed controls (P<0.05). Some females were permanently damaged from exposure to phosphine and did not reproduce even when given access to males. We also examined the additional effects of starvation prior to phosphine exposure on offspring production. Non-exposed starved females experienced a small reduction in mean offspring production in the week following starvation, followed by a recovery in the second week. Females that were starved and exposed to phosphine demonstrated a very significant reduction in offspring production in the first week following exposure which remained significantly lower than that of starved non-exposed females (P<0.05). These results demonstrate a clear sublethal effect of phosphine acting on the female reproductive system and in some individuals this can lead to permanent reproductive damage. Pest population rebound after a fumigation may be slower than expected which may reduce the rate of phosphine resistance development. The results presented strongly suggest that phosphine resistance models should include sublethal effects.
红粉甲虫是一种世界性的储粮害虫和储粮产品害虫。这种害虫已经对磷化氢产生了抗药性，磷化氢是主要用于防治它的化学物质。幸存者的繁殖产量是抗性发展的一个重要因素，但缺乏实验数据。我们将交配后的抗性雌性甲虫暴露在 25°C 下，用 0.135 mg/L 的磷化氢处理 48 小时。经过一周的恢复，我们给一半暴露在磷化氢中的雌性甲虫和一半未暴露的对照组雌性甲虫提供了两只未暴露的雄性甲虫。暴露在磷化氢中的雌性甲虫产生的后代明显少于未暴露的雌性甲虫。与未暴露的对照组（P<0.05）相比，单独隔离的雌性甲虫产生的后代明显更少。有些雌性甲虫因暴露在磷化氢中而受到永久性损伤，即使给予雄性甲虫也不会繁殖。我们还研究了在暴露于磷化氢之前饥饿对后代产生的额外影响。未暴露的饥饿雌性甲虫在饥饿后第一周的平均后代数量略有减少，随后在第二周恢复。饥饿并暴露于磷化氢的雌性甲虫在暴露后的第一周表现出非常显著的后代产量减少，这仍然明显低于饥饿未暴露的雌性甲虫（P<0.05）。这些结果表明，磷化氢对雌性生殖系统有明显的亚致死作用，在某些个体中，这可能导致永久性生殖损伤。熏蒸后害虫种群的反弹可能比预期的要慢，这可能会降低磷化氢抗性的发展速度。研究结果强烈表明，磷化氢抗性模型应包括亚致死效应。
