食蚜瘿蚊对烟蚜的捕食作用

Predation Ability of the Gall Midge Aphidoletes aphidimyza(Rondani)on Tobacco Aphid Myzus persicae(Sulzer)

为研究食蚜瘿蚊不同龄期幼虫对不同龄期烟蚜的捕食能力,通过室内试验评估不同龄期食蚜瘿蚊幼虫的捕食功能反应和食蚜瘿蚊3龄幼虫对不同龄期烟蚜的种内干扰作用。结果表明,食蚜瘿蚊幼虫对不同龄期烟蚜的捕食功能反应均为Ⅱ型,其中2龄食蚜瘿蚊幼虫对1~2龄烟蚜的处理时间短(2.0525 h),理论最大捕食量最大(11.69头);3龄食蚜瘿蚊幼虫对不同龄期烟蚜的控制作用均强于2龄食蚜瘿蚊幼虫,对高龄烟蚜(3~4龄)的控制效果最为明显;食蚜瘿蚊3龄幼虫对不同龄期烟蚜的日均捕食量随着食蚜瘿蚊密度的增加而显著增大,但平均捕食率随着食蚜瘿蚊密度的增加而逐渐减小。食蚜瘿蚊捕食不同龄期烟蚜的种内干扰作用不同,干扰程度为1~2龄(0.76)>4龄(0.64)>3龄(0.57)。因此,食蚜瘿蚊对烟蚜的控制潜能较大,是一种可应用的蚜虫天敌。

In order to investigate the predatory potential of the predatory gall midge Aphidoletes aphidimyza(Rondani)on different instar stages of tobacco aphid Myzus persicae(Sulzer),we studied the functional response of second and third instar larvae of A.aphidimyza and intraspecific interference effects of third instar larvae of the predatory midge.Our results showed that when fed with tobacco aphids at different instar stages,the functional response of second and third instar larvae of the midge fit the model type II.Second instar larvae of the predatory midge have the shortest handing time(2.0525 h)and the highest theoretical predation amount(11.69)when fed with first or second instar tobacco aphids.Third instar larvae of the predatory midge have higher potential predation compared to second larvae and better suppression effect on older instar tobacco aphids.Daily predation of third instar larvae on different instars tobacco aphids were obviously increased with increased density of predatory midge,but the average predation rate was the opposite.Intraspecific interference effects of third instar larvae were varied when fed with different instars tobacco aphid M.persicae.The interference degree when feed on tobacco aphid M.persicae was first to second instar(0.76)>fourth instar(0.64)>third instar(0.57).In summary,the predatory midge A.aphidimyza has a high potential with suppression control ability that can be used to control tobacco aphid M.persicae.