【摘要】 在过马营乡（青海省海南藏族自治州）对锐劲特控制草原蝗虫的作用进行了笼罩和野外实验。目的在于分析该新杀虫剂对草原蝗虫的作用方式，特效性及野外应用之最低剂量。红翅皱膝蝗（Ａｎｇａｒａｃｒｉｓｒｈｏｄｏｐａ），宽须蚁蝗（Ｍｙｒｍｅｌｅｏｔｅｔｔｉｘ　ｐａｌｐａｌｉｓ）和狭翅雏蝗Ｃｈｏｒｔｈｉｐｐｕｓ　ｄｕｂｉｕｓ被选用作实验材料。结果表明极低剂量的锐劲特（４ ｇ和 ８ ｇ／ｈａ活性物质）便对蝗虫有很强的触杀和胃毒作用。在笼内，两种不同浓度的锐劲特的药效几乎没有差别。除了宽须蚁蝗成虫，触杀的击倒作用一般较胃毒的迅速；锐劲特对狭翅雏蝗 ５龄蝻的控制作用达 ２周以上。在野外对 ４个剂量的锐劲特（２，３，５和 １０ ｇ活性物质／ｈａ）及 ５个剂量的 ２０％的杀灭灵（９０， ７５， ６０， ４５， ３０ ｇ活性物质／ｈａ）的短期防效进行了比较。锐劲特的短期防效较杀灭灵为好。不同剂量的锐劲特间的区别主要表现在处理后不同时间内蝗虫的死亡率，在短期控制效果上几乎没有差别。施用锐劲特２６天后，喷洒过 ３ ｇ活性物质／ｈａ以上剂量的实验小区内草原蝗虫的密度仍处于极低水平，表明该药野外施用的最低剂量为３ｇ活性物质／ｈａ。更多还原

【Abstract】 Cage and field experiments with Fipronil were carried out in Guomaying (Hainan Tibetan Autonomous Prefecture, Qinghai Province) to determine the mode of action, persistence, and the lowest dosage required of this new insecticide in the management of pasture grasshoppers. Three dominant species Angaracris rhodopa, Myrmeleotettix palpalis and Chorthippus dubius were chosen as the experimental materials. The results showed that Fipronil was a powerful contact and stomach poison against different grasshoppers at very low dosages of 4 and & g a. i/ha. In the cages, the difference between the effects of 4 and & g a. i. /ha of Fipronil on grasshoppers was usually negligible. The knocking down effects of contact were obviously quicker than that of stomach effect ; no such difference was, however, found in the tests with the adults of M. palpalis. The persistent effect of Fipronil on the sib instar of C. dubius nymphs was over 2 weeks. Four levels of Fipronil (2, 3, 5 and 10 g a. i. /ha) and five levels of 20% of Shamieling (90, 75, 60, 45, 30 g a. i. /ha) were compared in the field. The immediate effect of Fipronil was stronger than that of Shamieling. Differences among the effects of different dosages of Fipronil were mainly shown in terms of survival rate of grasshoppers after the treatment. There was almost no difference as to control results. Twenty-six days after the treatment, the densities of grasshoppers remained at very low level in the quadrats treated by Fipronil at 3 g a. i. /ha or more. This suggested that the lowest dosage required was 3 g a. i. /ha in the field operation.更多还原