贵州玉米新害虫——直刺细铁甲的生物学特性

Biological characteristics of a new corn pest—Rhadinosa fleutiauxi(Baly)

直刺细铁甲Rhadinosa fleuaauxi（Baly）是近年来在玉米上新发现的害虫，为了制定科学的防治对策，通过田间调查和室外养虫笼接虫饲养的办法对其生物学特性进行了系统研克。结果表明，该虫在毕节地区1年发生1代，以成虫在土埂子边、沟边及荒地的杂草丛中越冬，越冬寄主有茅草、马耳朵草等。卵、幼虫和蛹的历期在不同温度下存在差异，温度越高历期越短。卵历期为8．90-11．98d，死亡率为30．18％～44．74％；幼虫历期为18．82—23．85d，死亡率为19．61％～37．04％；蛹历期为12．26—12．43d，未发现死亡现象。成虫产卵方式为散产，调查发现92．61％的卵粒产在寄主植物叶片边缘或叶尖，幼虫只在一个虫道里取食，不会转移危害；成虫具有群居性和假死性，耐饥饿能力较强，在不供给食物取食的情况下可存活（9．30±2．29）d。

Rhadinosafleutiauxi （Baly） is a new pest on corn in Guizhou province. In order to work out the scientific method, the biological characteristics of the pest were studied in field and in cage. The result showed and that the pest has one generation in a year and overwinters as imago in clumps of weeds. The durations of eggs, larvae and pupae are varying with temperature changing. The higher the temperature, the shorter the duration. Egg＇ s durations are 8. 90 - 11.98d and its mortalities are 30. 18%-44.74%. Larvae＇ durations are 18.82-23. 85d and its mortalities are 19.61% - 37. 04%. Pupae＇ durations are 12. 26 - 12. 43d and no death was found. The patterns that pupae produce egg are dispersed. We found that 92.61% eggs were produced on the leaf edge or tip of its host plant, and the larvae take food only through one route in one generation, and don＇ t damage the other parts of the host plant. Pupae have the characteristics of flock and falsedeath, their endurable abilities are strong, they can survive for （9.30 ± 2.29）d under no supply.