硅藻土对5种储粮害虫和不同磷化氢抗性水平杂拟谷盗防治效果的研究

为初步了解硅藻土对储粮害虫的防治效果以及与害虫磷化氢抗性发生发展的关系, 本研究采用直接拌粮法(设置剂量梯度为0?0.2?0.4?0.6 g/kg和 0.8 g/kg)测定硅藻土对赤拟谷盗?杂拟谷盗?锈赤扁谷盗?谷蠹?玉米象的防治效果, 以及磷化氢抗性杂拟谷盗(抗性倍数为 2.3~144.7)对硅藻土的敏感性差异; 除此之外, 本研究还分析了0.4 g/kg硅藻土在 4 种粮食(小麦?玉米?大豆?稻谷)中对赤拟谷盗的杀虫效果?研究结果表明:一定剂量(0.2~0.8 g/kg)的硅藻土均能够在一定时间内有效杀死上述 5种储粮害虫, 不同储粮害虫对硅藻土的敏感性存在显著差异(P<0.05), 其中杂拟谷盗对硅藻土的耐受性最强, 玉米象对硅藻土最为敏感?除个别品系外, 不同磷化氢抗性品系的杂拟谷盗对硅藻土的敏感性不存在显著差异(P>0.05), 且与磷化氢抗性无关; 硅藻土在不同粮食中对害虫的作用效果存在显著性差异(P<0.05)(处理 7 d后, 死亡率为 13%~98%), 其中在大豆中对赤拟谷盗的杀虫效果最强, 在玉米中对其作用效果不明显?因此本研究得出结论:硅藻土对主要储粮害虫均具有一定的防治作用, 且对抗磷化氢的杂拟谷盗具有良好的致死效果?因此, 硅藻土具备成为储粮害虫防治及其磷化氢抗性治理药剂的潜力?

Control effect of diatomaceous earth on five stored grain pests and Tribolium confusum with different phosphine resistance levels

To explore the effect of diatomaceous earth (DE) on major stored grain pests, Tribolium castaneum, T.confusum, Sitophilus zeamais, Cryptolestes ferrugineus, Rhyzopertha dominica were exposed in DE with different doses (0, 0.2, 0.4, 0.6 g/kg and 0.8 g/kg) by mixing the pesticide with grain. The sensitivity of T.confusum with different phosphine-resistant levels (Rf 2.3-144.7) to DE was investigated. The effect of DE at 0.4 g/kg on T.castaneum in four different grains (wheat, corn, soybean and rice) was also analyzed. The results showed that a certain concentration of DE could kill the stored grain pests. The pests showed significant different sensitivity to DE (P<0.05), T.confusum had the strongest tolerance to DE, and S.zeamais was the most sensitive to DE. The sensitivity of four different phosphine-resistant T.confusum strains to DE were not related to resistance levels. Moreover, we also found that DE had significant different effects on pests in different grains (P<0.05)(The mortality rate was 13%-98% after 7 days of treatment). Among them, the effect of DE was the strongest in soybeans, while no significant effect in corn. Overall, the above results suggest that DE not only has a certain prevention and control effect on the main stored grain pests, but also has a good lethal effect on phosphine-resistant strains of T.confusum. Therefore, DE has the potential to be developed into an insecticide for controlling stored grain pests and managing phosphine resistance.