8种杀虫剂对苜蓿叶象及条纹根瘤象的毒力测定

Toxicity eveulation of 8 pestsides against Hypera postica and Sitona lineellus

采用喷雾法对8种药剂对苜蓿叶象及条纹根瘤象进行室内毒力测定,结果表明：2%噻虫啉微囊粉剂对苜蓿叶象四龄幼虫的活性较高,其 LC50为107.408 mg/L,4.5%高效氯氰菊酯微乳剂的活性最低,其 LC50为549.342 mg/L；8种杀虫剂对三龄幼虫的 LC50为140.176-453.784 mg/L。40%毒死蜱乳油对条纹根瘤象成虫活性较高,其 LC50为71.017 mg/L,其次为2%噻虫啉微囊粉剂,其 LC50为80.157mg/L。

Toxicities of the eight insecticidesagainst H ypera postica and Sitona lineellus were testd in this paper.The result showed that thiacloprid （2%）had higher toxicities to 4th larvae of H ypera postica .the LC50 was 107.408 mg/L.Pyrethroid（4.5%）had the lowest toxicities to 4th larvae of H ypera postica .the LC50 was 549.342 mg/L.The range of LC50 of eight insecticides against 3rd larvae of H ypera postica were from 140.176 to 453.784 mg/L.The chlorpyrifos （40%）had the higher toxicity against Sitona lineellus ,the LC50 was 71.017 mg/L.The thiacloprid （2%）had the lower toxicity to Sitona lineellus .The LC50 was 80.157 mg/L.