Species of Liriomyza Leafminers and Their Associated Parasitoids in the Cowpea Planted in Winter in Hainan Island

Key words: 
• Hainan Island /
• cowpea planted in winter /
• Liriomyza leafminer /
• parasitoid

Abstract: Liriomyza leafminers are common pests infesting cowpea Vigna sesquipedalis in Hainan Island,and their associated parasitoids are important natural enemies.For further conservation and promotion of the natural enemies for the control of leafminers,field surveys of the associated parasitoids and parasitism as well as the leafminers were conducted in the field of cowpea planted in winter in Haikou,Qionghai,Danzhou and Sanya,Hainan Province.Two species of leafminers and five species of their parasitoids were collected from the surveys.The relative abundances of the two species of leafminers,Liromyza trifolii（Burgess） and L.sativae Blanchard,were79.5% and 20.5%,respectively.Both L.trifolii and L.sativae were found at the four sampling sites,while L.trifolii was dominant in Haikou and Sanya,and L.sativave dominant in Qionghai and Danzhou.Of the five species of their parasitoids,Opius dimidiatus（Ashmead） belongs to the family of Braconidae,while Chrysocharis pentheus（Walker）,Hemiptarsenus varicornis（Girault）,Neochrysocharis formosa（Westwood） and N.punctiventris（Crawford） to the family of Eulophidae.O.dimidiatus and H.varicornis were relatively abundant with their high relative abundances being up to 51.8% and 29.2%,respectively.The parasitoids had different percentages of parasitism over the leaminers from site to site in a descending order:51.4% in Qionghai,45.4% in Sanya,17.0% in Danzhou and 10.5% in Haikou.They had a high diversity and parasitism percentage,and should,hence,be well conserved and utilized to control the two species of leafminers infesting cowpea planted in winter in the Island.