湖南桔园主要天敌对柑桔全爪螨的捕食作用及其综合评定

A SYNTHETICAL EVALUATION ON FUNCTIONAL RESPONSES AND EFFECTIVENESS OF FIVE SPECIES OF PREDATORS TO CITRUS RED MITE

1984—1988年调查了湖南桔园主要天敌——尼氏钝绥螨、深点食螨瓢虫、塔六点蓟马、中华草蛉、龟纹瓢虫的田间消长动态,测定了它们对柑桔全爪螨的捕食功能反应,均属于Holling Ⅱ型。5种主要天敌中,尼氏钝绥螨发生量最多,与柑桔全爪螨数量相关极为显著:中华草蛉的日捕食量最大,对柑桔全爪螨处置时间最短;深点食螨瓢虫食性较专一,对柑桔全爪螨瞬时攻击率最高。根据每种天敌的发生量、发生期、捕食能力及抗药性等4个因素,应用模糊分级方法综合评定对柑桔全爪螨控制作用大小依次为:尼氏钝绥螨、深点食螨瓢虫、塔六点蓟马、中华草蛉、龟纹瓢虫。这些天敌的综合作用可以控制正常年份柑桔全爪螨的为害。

In 1984—1988,the population dynamics of main natural enemies in citrus orchards in Hunan Province,namely,Amblyseius nicholsi,Stetho- rus punctillum,Scolothrips takahashi,Chrysopa sinica,and Propylaeo japoni- ca were investigated,and their functional responses to citrus red mite Panonychus citri were tested.In these predators,A.nicholsi was the dominant species with maximum density,and was closely related to the number of mite host.All the tracks of their functional responses be- longed to Holling′sⅡ equation.The feeding amount of C.sinica was at the most with the shortest handling time.The feeding habit of S.pun- ctillum was rather concentrated,and possessed the highest instantaneous attack rate.In accordance with the population densities,occurrence times,predatory capabilities,and pesticide resistances,the control ef- fects of these five predators were synthetically determined by fuzzy classification as:A.nicholsi>S.punctillum>S.takahashi>C.sinica>P. japonica.In general years in Hunan Province,the P.citris may be con- trolled by the synthetical effect of these predators.