蠋蝽成虫对两种烟草害虫卵及3龄幼虫的捕食功能反应

Predatory functional responses of Arma chinensis(Fallou)to the eggs and 3rd-instar larvae of two tobacco pests

为探究蠋蝽对两种烟草害虫烟青虫和斜纹夜蛾的捕食能力,在室内可控条件下开展了蠋蝽雌雄成虫对烟青虫和斜纹夜蛾卵及3龄幼虫的捕食试验,利用HollingⅡ功能模型拟合蠋蝽雌雄成虫对烟青虫和斜纹夜蛾的捕食功能反应。结果表明,蠋蝽雌成虫对烟青虫和斜纹夜蛾的瞬时攻击率为:烟青虫3龄幼虫(1.056)>斜纹夜蛾卵(1.055)>烟青虫卵(1.035)>斜纹夜蛾3龄幼虫(0.973);控害效应高低为:烟青虫卵(152.21)>斜纹夜蛾卵(124.18)>烟青虫3龄幼虫(15.09)>斜纹夜蛾3龄幼虫(9.63);蠋蝽雄成虫对烟青虫和斜纹夜蛾的瞬时攻击率为:烟青虫卵(1.060)>斜纹夜蛾卵(1.056)>烟青虫3龄幼虫(0.825)>斜纹夜蛾3龄幼虫(0.760);控害效应高低顺序为:斜纹夜蛾卵(111.16)>烟青虫卵(101.92)>烟青虫3龄幼虫(8.87)>斜纹夜蛾3龄幼虫(7.04)。随着烟青虫和斜纹夜蛾密度的增加,蠋蝽成虫的搜寻效应会逐渐下降。研究结果表明蠋蝽雌雄成虫对烟青虫和斜纹夜蛾具有良好的防控能力,因此,可结合害虫预测预报,在烟青虫和斜纹夜蛾产卵高峰期和3龄幼虫发生前期大量释放蠋蝽成虫以降低两种害虫的种群数量,减少其对烟草的危害。

To explore the predatory potential of Arma chinensis against Heliothis assulta and Spodoptera litura,the predation of the eggs and 3rd-instar larvae of H.assulta and S.litura by A.chinensis adults was measured under controlled conditions in the laboratory.The predatory functional responses of A.chinensis adults fitted the HollingⅡfunction model.The instantaneous attack rates of A.chinensis female adults to the pests from high to low were:the 3rd-instar larvae of H.assulta(1.056),eggs of S.litura(1.055),eggs of H.assulta(1.035),the 3rd-instar larvae of S.litura(0.973).The predation capacities from high to low were:eggs of H.assulta(152.21),eggs of S.litura(124.18),3rd-instar larvae of H.assulta(15.09)and 3rd-instar larvae of S.litura(9.63).The instantaneous attack rates of A.chinensis male adults to the pests from high to low were:eggs of H.assulta(1.060),eggs of S.litura(1.056),3rd-instar larvae of H.assulta(0.825),3rd-instar larvae of S.litura(0.760).The predation capacities from high to low were:eggs of S.litura(111.16),eggs of H.assulta(101.92),3rd-instar larvae of H.assulta(8.87),and 3rd-instar larvae of S.litura(7.04).With increasing densities of H.assulta and S.litura,the searching efficiency of A.chinensis adults decreased gradually.This study suggested that A.chinensis adults had a good control ability against H.assulta and S.litura.Combined with pest forecast and prediction,releasing a large number of A.chinensis adults during the oviposition peak period and occurrence prophase of 3rd-instar H.assulta and S.litura can help reduce the pest population size and decrease its damage to tobacco.