甲酸乙酯对土耳其扁谷盗的熏蒸作用

采用密闭熏蒸法研究了甲酸乙酯在不同条件下对土耳其扁谷盗卵、低龄幼虫、高龄幼虫、蛹和成虫的致死作用．在28 ℃条件下，以体积分数为0.040和0.045的药剂处理土耳其扁谷成虫12　h，其校正死亡率分别为88.633%和99.453%；以体积分数为0.035的药剂在15，18，21，24，27，30，33　℃下处理24　h，校正死亡率分别为84.367%，88.087%，92.376%，74.266%，63.252%，60.935%，58.775%，表明甲酸乙酯具有良好的速效性，且在相对低温时比在相对高温时熏蒸效果好.在20，25，30　℃条件下，熏蒸处理土耳其扁谷盗成虫24　h，其半致死体积分数LC50为0.014 31，0.017 335，0.021 073；处理48　h时则分别为0.012 828，0.015 446，0.020 068，质量浓度为30　g/m3的甲酸乙酯处理土耳其扁谷盗卵，低龄幼虫，高龄幼虫和蛹24　h，对应死亡率为93.372%，99.782%，96.638%，91.645%，表明甲酸乙酯对土耳其扁谷盗低龄幼虫熏蒸效果最好，蛹和卵对甲酸乙酯具较强的抗药性.

Fumigation Activity of Ethylformate Against Cryptolestes Turcicu (Grouville)

This paper systematically studied,with the sealed jar fumigation method under different conditions,the effects of ethylformate (EtF) on eggs,early larvae,late larvae,pupae and adults of C.turcicus.Experiments signify the corresponding corrected mortalities of adults were 88.633% and 99.453% with 0.040 and 0.045 EtF volume ratio after 12　h fumigation under 28　℃.And the adult corrected mortalities were 84.367%,88.087%,92.376%,74.266%,63.252%,60.953% and 58.775% respectively with 35　μL/L dosage after 24 h fumigation under 15,18,21,24,27,30 ℃  and 33 ℃.These results indicated that the EtF killed the adult weevils in a very short time period,and the fumigation efficacy was better at relatively lower temperature than that at relatively higher temperature.Under the conditions of 20,25,30 ℃ after 24 h fumigation,the volume ratio LC50　s were 0.014 311，0.017 335　and 0.021 073 respectively,whereas after 48　h fumigation,the corresponding volume ratio LC50　s were 0.012 828，0.015 446 and 0.020 068.Fumigating the immature stages of C.turcicus 24　h with 30　g/m３ dosage EtF,the mortalities of eggs,early larvae,late larvae and pupae of were 93.372%,99.782%,96.638% and 91.645% respectively，which proved that the fumigation activity of EtF was the best against early larvae,and the pupae and eggs possessed a relatively high endurance to EtF.