水葫芦象甲的寄主专一性及对水葫芦的控制作用  

The host specificity of water hyacinth weevils and their controlling effects against water hyacint in Ningbo district

作　　者：陈若霞[1] 叶恭银[1] 王扬军 古斌权 张春芬 应霞铃 沈健 

机构地区：[1]浙江大学农业与生物技术学院,浙江杭州310029 [2]宁波市农业科学研究院生态环境研究所,浙江宁波315040 [3]余姚市农业信息中心,浙江余姚315400

出　　处：《浙江农业学报》2005年第2期74-78,共5页Acta Agriculturae Zhejiangensis

基　　金：宁波市重大农业科研行动项目(200019)

摘　　要：水葫芦象甲10科12种作物的寄主专一性测定结果表明,在选择性和非选择性条件下,该象甲的幼虫在植株间的转移性极差,大多在被测植物上存活2～5d后死亡,成虫则可能因气温等自然条件不同而在被测植物上存活10～62d,幼虫和成虫均不在被测植物上取食、寄生与产卵。象甲的成虫取食水葫芦叶片的正面叶肉、叶柄上部、匍匐枝与花柄表面形成取食斑,产卵于叶柄上中部;幼虫寄生于叶柄海绵组织内,形成向下的寄生通道,并自叶柄基部钻出在根表面纠集根毛化蛹;高龄幼虫对水葫芦的控制作用明显大于成虫和低龄幼虫。象甲对水葫芦的控制作用随其群体量的增加而逐步提高,当成虫和幼虫总量分别低于15,60头/m2时,对水葫芦的控制作用不明显;当成虫和幼虫总量分别超过25,190头/m2时,控制作用明显增强;当成虫和幼虫总量分别超过130,450头/m2时,天敌对水葫芦的控制作用达到顶峰,最终可使水葫芦密度比对照减少52.69%,株高下降67.19%,单株叶片数减少29.42%,最大叶直径减少41.33%,生物量减少64.82%。The measurement of host specificity of water hyacinth weevils (Neochetina eichhorniae and Neochetina bruchi)against 12 plant species from 10 families showed that both under multiple-choice and no-choice feeding conditions,the weevils only attacked and completed their life cycle on water hyacinth. It was almost impossible for the weevil larvae to move from one plant to another,and larvae can keep alive for only 2-5 days on plants tested. The weevil adults could survive on plants tested for 10-62 days,probably depending on temperature conditions. Both weevil larvae and adults could not feed and attack plants tested, and adults also could not lay eggs on tested plants. The adult fed on the epidermal of leaves and petioles and flower stems, and laid eggs inside the leafstalk of host plant. The larvae tunneled inside the petiole and completed their growth, then pupated underwater attaching to living root of water hyacinth. So the older instar larvae could control water hyacinth more effective than did younger instar larvae and adult. The effect of weevil on controlling water hyacinth enhanced with population of weevils increased. The controlling effect of the weevils was not marked as the population densitywas less than 15 adults and 60 larvae/m^2, and become more obvious as the density was more than 25 adults and 190 larvae/m^2.The highest controlling effect was obtained from the density was more than 130 adults and 450 larvae/m^2.The plant density, plant height,leaf number per plant and the longest leaf diameter, and biomass of the water hyacinth plants of the treatment receiving weevils decreased 52.69%, 67.19%,29.42%,41.33%, and 64.82%, respectively, compared with the control treatment.

关 键 词：水葫芦象甲 寄主专一性 控制作用 水葫芦 

分 类 号：S482.4[农业科学—农药学]