Abstract:

To estimate scientifically the risk of this species and take effective measures, it’s necessary to investigate the infected region and potential distribution of the species in Yunnan Province. Ecological niche model technique, genetic algorithm for rule-set prediction (GARP), was used to predict potential distribution of the seed chalcids, Megastigmus duclouxiana Roques & Pan in Yunnan province based on associations between known occurrence records and a set of environmental variables. The results of Chi-square test were 216.6＜x2＜269.5 (1.50×10-60＜P＜4.95×10-49) for 10 best models, indicating that these models had statistical significance for predicting the potential geographical distribution. The suitable areas for Megastigmus duclouxiana infestations were over two thirds of total area of Yunnan province. The highly suitable was middle Yunnan plateau and its two sides ranged from 24°N to 26°N, where the annual average temperature was 14.5℃. The moderate suitable included minor counties of southwest Yunnan, south Yunnan and southeast Yunnan. The low suitable was located in Wenshan autonomous prefecture, including Wenshan, Maguan, Xichou, Malipo and Funing county. Low and hot valley, Diqing autonomous prefecture and Zhaotong municipality were predicted as unsuitable, where the climate was cold zone, temperate zone or tropical one. Large area of Yunnan province was suitable for Megastigmus duclouxiana infestations except for Zhaotong, Diqing and low and hot valley.