Population Dynamics And Community Characteristics Of Insect Pests And Their Natural Enemies On Cherry Blossom Leaves

Population dynamics of insect pests and their natural enemies and community structure characters of insect community on cherry blossom leaves were studied in Laiwu City, Shandong Province, China in 2009.1. There were 21 species of insect pests belonging to 11 Orders, 2 Classes and 31 species of natural enemies belonging to 5 Orders, 2 Classes in the systemic sampling and general investigation. Fifteen species of insect pests and twenty-eight species of natural enemies were investigated in the systemic sampling.2. The poplation dynamics of aphids (Myzus persicae and Aphis citricola) , spider mites(Tetranychus viennensis and Panonychus ulmi), Empoasca flavescens, Stephanitis nashi and their natural enemies were analyzed. The predatory ladybird beetles and Orius minutus synchronized with the occurrence of two species of aphids, and some obligatory predators, such as Stethorus punctillum, Scolothrips takahashii, one predatory mite synchronized with the occurrence of two species of spider mites, showing that those natural enenmies were important natural control factors limiting the growth of aphids and spider mites.3. In the insect community on cherry blossom leaves, the number of pest species in Aphididae, Limacodidae, Pentatomodae and Tetranychidae was more abundant, the relative abundance of Aphididae, Tingidae, Cicadellidae,Tetranychidae was high; the number of natural enemy species in Coccinellidae, Chrysopidae, Syrphidae, Aphidiidae and Braconidae was more abundant, the relative abundance of Coccinellidae, Chrysopidae, Anthocoridae, Thripidae, Cicadellidae, Aphidiidae, Aphelinidae, Linyphiidae and Phytoseiidae was high.4. The dominance and dominant species of insect pests and their natural enenmies in the community were analyzed. The dominant species of insect pests were Myzus persicae, Aphis citricola, Tetranychus viennensis, Empoasca flavescens and Stephanitis nashi. The dominant species of natural enemies were Aphidius gifuensis, Chrysopa septempunctata, Harmonia axyridis, Oruus minutes, Propylaea Japonica, Stethorus punctillum, Scolothrips takahashii.5. The dynamics of species richnee, diversity, ecological dominance, and evenness were analyzed in temporal sequence. The factors affecting the insect community, such as the growth stages of cherry blossom, rainfall and the occurrence of insect pests were also analyzed.6. The temporal pattern of the cherry blossom insect community was analyzed by the optimal sorting method and grouped into four continous periods. The occurrence characteristics of these pests and nature enemies in each temporal period were analyzed.