豆大蓟马在海南的发生动态及其卵和蛹的防治药剂初筛

Occurrence of Megalurothrips usitatus in Hainan and preliminary screening of insecticides for control of its eggs and pupae

为明确豆大蓟马(Megalurothrips usitatus)在海南的时空动态、种群体型差异及筛选高效卵和蛹杀灭剂,笔者系统调查了豆大蓟马在海南豇豆主产区的全年发生动态,测量了不同地理位置种群成虫的体型大小,并采用浸渍法和POTTER喷雾法分别测定了多种杀虫剂对豆大蓟马卵和蛹的室内毒力。结果表明,豆大蓟马在海南可全年发生,种群动态受寄主生育期和温度双重调控;儋州种群的雌雄个体的体长和体宽显著大于三亚种群和澄迈种群;螺虫乙酯对豆大蓟马卵具有较高的毒力(LC50=18.51 mg·L^(−1)),而乙基多杀菌素和溴虫腈则对蛹具有较高的活性,LC50分别为26.18和27.71 mg·L^(−1),可推荐作为豆大蓟马卵和蛹的田间防治药剂。

To clarify the spatiotemporal dynamics of the thrips Megalurothrips usitatus Bagnall populations and the differences of the thrips populations in adult body size in Hainan,China and screen high effective insecticides for control of thrips eggs and pupae,a systematical investigation was made into the annual occurrence of M.usitatus on cowpea in Hainan,the adult body size of the M.usitatus populations at different geographical locations were measured,and the toxicity of various insecticides against the eggs and pupae of M.usitatus was tested by using the dip method and POTTER bioassay,respectively.The investigation showed that M.usitatus occured throughout the year in Hainan.Population dynamics were significantly regulated by host phenology and temperature.The adult body size measurement showed that the adult body length and body width of M.usitatus populations were significantly higher in Danzhou than in Sanya and Chengmai.The toxicity test showed that spirotetramat had a higher ovicidal activity(LC50=18.51 mg·L^(−1))against M.usitatus eggs,while spinosad and chlorfenapyr had a higher activity against M.usitatus pupae,with their LC50 values being 26.18 and 27.71 mg·L^(−1),respectively.These insecticides could hence be recommended as candidates for controlling M.usitatus eggs and pupae in the field.