叉角厉蝽对于不同虫龄茶谷蛾幼虫的捕食功能反应

Functional Response of Eocanthecona furcellate(Hemiptera:Pentatomidae)to Different Instars of Agriophara rhombata Meyr.

为了探索叉角厉蝽Eocanthecona furcellate对茶谷蛾Agriophara rhombata Meyr.的控害作用,在实验室及田间测定了不同虫态叉角厉蝽对于不同虫龄茶谷蛾幼虫的捕食能力,研究了该蝽对于茶谷蛾幼虫的捕食功能反应、搜寻效应、干扰作用及田间控害效应。结果表明:叉角厉蝽对不同虫龄茶谷蛾都有捕食作用,总体呈现出若蝽对茶谷蛾低龄幼虫的捕食量大于高龄幼虫,成蝽对高龄幼虫的捕食量大于低龄幼虫;对不同虫龄茶谷蛾幼虫的捕食作用均符合HollingⅡ圆盘方程,其中对1~2龄幼虫的捕食效能(a/Th)最强(30.2886),日最大捕食量(1/Th)最大(28.6588头)。对不同虫龄茶谷蛾的搜寻效应与其密度呈负相关,且对低龄幼虫的搜寻效应显著大于高龄幼虫。建立了叉角厉蝽密度、不同虫龄茶谷蛾密度对捕食作用的干扰反应方程,干扰发生后该蝽的捕食量及捕食作用率逐渐下降。田间控害试验表明:4~5龄若蝽对茶谷蛾低龄幼虫的防效显著高于5~6龄幼虫,在第7 d时,对1~2龄幼虫的防效达42%;成蝽对3~4龄幼虫的防效较好,在第7 d时达到47%。

To explore the control pentital of Eocanthecona furcellate(Hemiptera:Pentatomidae)against Agriophara rhombata Meyr,the predatory abilities of different stages of E.furcellate on different instars of A.rhombata were measured in laboratory and field,along with the measurement of predatory function response,searching efficiency,disturbance effect and field control.The results showed that E.furcellate preyed on the different instars of A.rhombata,with nymph preying more on the younger larvae than on the older larvae and the adults preying more on the older larvae than on the younger larvae.The predation to A.rhombata larvae fitted with the Holling II equation,the predatory efficiency(a/Th)was the highest(30.3)and the daily maximum predation(1/Th)was the highest(28.7)for the 1^(st) to 2^(nd) instar larvae.The searching efficiency against different instars was negatively correlated with their densities,significantly higher against the young larvae than the old larvae.An equation describing the disturbance responses to densities of E.furcellata and A.rhombata larvae was established,which shows that the predatory capacity and rate of E.furcellata decreased gradually after the disturbance occurred.The field experiments showed that the control efficiency of the 4-5 predator instars against young A.rhombata larvae was significantly higher than that of 5-6 predator instars,and the control efficiency against 1-2 A.rhombata instars reached 42% on the 7th day.The control efficiency of adults against the 3rd to 4th A.rhombata instars was the highest,reaching 47% on the 7th day.