Laboratory tests were carried out in order to evaluate the efficacy of five inert dust （Puliangtai, G-1, G-2, G-3 and G-4） against the high level phosphine resistance Cryptolestesferrugineus （Stephens）. The relati...Laboratory tests were carried out in order to evaluate the efficacy of five inert dust （Puliangtai, G-1, G-2, G-3 and G-4） against the high level phosphine resistance Cryptolestesferrugineus （Stephens）. The relative phosphine resistance of two strains of Cryptolestesferrugineus （Stephens） was measured by the method of knockdown at 2 mg/L of phosphine. The insects were exposed to the five inert dust on filter paper inside petri dishes for 1 day at 30 ±1℃and 65 ±1% relative humidity. Then, the adults were held for 4 days with food at the same conditions without inert dust in surface bioassay. Also, they were placed in 25 ±1℃ and 65 ±1% relative humidity in grain bioassay. In surface bioassay, two strains （JXCF and YYCF） ofCryptolestesferrugineus （Stephens） were susceptible to the five inert dust at 0.08 g/m2 and 0.1 g/m2. G-3 appeared the most effective treatment against both strains, since its efficacy was 3-6 times higher than the other four inert dust tested. YYCF strain was more susceptible than JXCF, with 1-4 times higher mortality level. This research indicated that inert dusts were effective on phosphine-resistance Cryptolestesferrugineus （Stephens） populations.展开更多
文摘Laboratory tests were carried out in order to evaluate the efficacy of five inert dust （Puliangtai, G-1, G-2, G-3 and G-4） against the high level phosphine resistance Cryptolestesferrugineus （Stephens）. The relative phosphine resistance of two strains of Cryptolestesferrugineus （Stephens） was measured by the method of knockdown at 2 mg/L of phosphine. The insects were exposed to the five inert dust on filter paper inside petri dishes for 1 day at 30 ±1℃and 65 ±1% relative humidity. Then, the adults were held for 4 days with food at the same conditions without inert dust in surface bioassay. Also, they were placed in 25 ±1℃ and 65 ±1% relative humidity in grain bioassay. In surface bioassay, two strains （JXCF and YYCF） ofCryptolestesferrugineus （Stephens） were susceptible to the five inert dust at 0.08 g/m2 and 0.1 g/m2. G-3 appeared the most effective treatment against both strains, since its efficacy was 3-6 times higher than the other four inert dust tested. YYCF strain was more susceptible than JXCF, with 1-4 times higher mortality level. This research indicated that inert dusts were effective on phosphine-resistance Cryptolestesferrugineus （Stephens） populations.
