Tingbang Yang1, Jie Liu1, Longyu Yuan1, Yang Zhang1, Yu Peng1, Daiqin Li2, Jian Chen1. 1. Centre for Behavioural Ecology and Evolution (CBEE) and Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, China. 2. Department of Biological Sciences, National University of Singapore, Singapore.
Abstract
BACKGROUND: Predatory natural enemies play key functional roles in integrated pest management. However, the screening and evaluation of the main predators of insect pests has seldom been reported in the field. Here, we employed comprehensive indices for evaluating the predation of a common pest (Ectropis obliqua) by nine common spider species in Chinese tea plantations. RESULTS: We established the relative dominance of the spider species and their phenological overlap with the pest species, and analyzed DNA from the nine spider species using targeted real-time quantitative polymerase chain reaction to identify the residual DNA of E. obliqua. The predation rates and predation numbers per predator were estimated by the positive rates of target fragments and the residual minimum number of E. obliqua in predators' guts, respectively. The results showed that only four spider species preyed on E. obliqua, and the order of potential of the spiders to control E. obliqua from greatest to smallest was Neoscona mellotteei, Xysticus ephippiatus, Evarcha albaria and Coleosoma octomaculatum by the Z-score method. CONCLUSION: The orb-weaving spider N. mellotteei has the maximum potential as a biological control agent of E. obliqua in an integrated pest management strategy. An approach of screening and evaluating main predators of insect pests through comprehensive indices was preliminarily established.
BACKGROUND: Predatory natural enemies play key functional roles in integrated pest management. However, the screening and evaluation of the main predators of insect pests has seldom been reported in the field. Here, we employed comprehensive indices for evaluating the predation of a common pest (Ectropis obliqua) by nine common spider species in Chinese tea plantations. RESULTS: We established the relative dominance of the spider species and their phenological overlap with the pest species, and analyzed DNA from the nine spider species using targeted real-time quantitative polymerase chain reaction to identify the residual DNA of E. obliqua. The predation rates and predation numbers per predator were estimated by the positive rates of target fragments and the residual minimum number of E. obliqua in predators' guts, respectively. The results showed that only four spider species preyed on E. obliqua, and the order of potential of the spiders to control E. obliqua from greatest to smallest was Neoscona mellotteei, Xysticus ephippiatus, Evarcha albaria and Coleosoma octomaculatum by the Z-score method. CONCLUSION: The orb-weaving spider N. mellotteei has the maximum potential as a biological control agent of E. obliqua in an integrated pest management strategy. An approach of screening and evaluating main predators of insect pests through comprehensive indices was preliminarily established.