Landscape diversity regulates diamondback moth populations on small spatial scales
Author of the article:ZHANG Jie；HE Wei-Yi；YANG Guang；HUANG Bin；HOU You-Ming
Author's Workplace：State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou 350002, China; Key Laboratory of Integrated Pest Management for Fujian-Taiwan Crops, Ministry of Agriculture, Fuzhou 350002, China; Key Laboratory of Insect Ecology in Fujian, Fuzhou 350002, China
Key Words：diamondback moth; abundance; natural habitat; natural enemies; sustainable control
Abstract：
[Objectives] To develop a sustainable method for controlling the diamondback moth (DBM), Plutella xylostella, which inflicts serious damage on cruciferous vegetable crops, by investigating the effects of landscape diversity on DBM and predatory spider populations. [Methods] Sampling sites were chosen based on an increasing diversity gradient in Fujian Province and the landscape composition was analyzed at radii of 25, 50, 100 m. The effect of landscape diversity on DBM abundance, fecundity and crop damage, and on spider abundance, was analyzed. [Results] DBM abundance decreased significantly as the percentage of natural habitat increased. Its fecundity was highest in landscapes with moderate diversity but there was no significant landscape effect on crop damage. Spider abundance had the opposite trend. Principal component analysis (PCA) indicates negative correlations between the percentage of grassland, forest and water and DBM abundance. [Conclusion] Improving landscape diversity, specifically maintaining more grassland, is an effective way of controlling DBM at spatial scales less than 100 m.