天敌昆虫田间捕食作用与能力的研究,通常采用田间种群数量调查与分析的方法或笼罩试验来评价其控制作用,但往往与实际情况不符,尤其是对可捕食多种猎物的非专食性天敌,很难说明其在田间对某一特定猎物的控制作用究竟有多大,而分子生物学技术为捕食者一猎物关系评价研究提供了新途径。本文系统介绍了基于种特异性SS-PCR标记技术和TaqMan-MGB实时荧光定量PCR技术的捕食性天敌控害作用定量评价方法及其优缺点,旨在为害虫天敌的种类筛选及其保护利用提供技术指导。
Field population investigation, dynamic analysis and enclosure studies are usually used to evaluate the predatory ability of the natural enemies of pest insects. However, the results obtained via these methods are always inconsistent with the actual situation, and consequently cannot explain the control efficacy of natural predators with regard to a specific prey species, especially, when the predators are generalists. Nowadays, molecular biological techniques provide a new approach for evaluating relationships between predator and prey. We here introduce a method based on TaqMan real-time PCR (with MGB probe) and species-specific PCR that was developed to quantitatively evaluate the control efficacy of generalist predators, and discuss its advantages and disadvantages. The present method should be useful for the screening, protection and utilization of natural enemies in the field.