タバコシバンムシ虫体の条件がリン化水素によるノックダウン時間に及ぼす影響

抄録

In a previous study, we developed an accurate and laborsaving method to determine the effective phosphine concentration for the fumigation of cigarette beetles based on the knockdown time. To successfully control beetles with phosphine, it is important to evaluate the resistance level of the target beetle population in advance. However, the population often contains males and females, mated and unmated, and adult beetles of different ages, and the effects of these factors on the knockdown time were unclear. In the present study, we investigated the effects of sex, mating status, adult age, and prior exposure to phosphine in the pupal stage on the knockdown time using a phosphine-resistant strain IWT. The log KT₅₀ value of the strain IWT was ca. 3.5 regardless of sex, experience of mating, adult age and experience of prior exposure, demonstrating that these factors are not important in evaluating the resistance level using knockdown time. The recommended phosphine concentration for the strain IWT was ca. 450–530 ppm, while the recommended concentration for a susceptible strain TSC was ca. 35 ppm.