海南岛芒果扁喙叶蝉的研究

芒果扁喙叶蝉是海南岛芒果树的重要害虫之一。成、若虫为害花芽、叶芽、花穗、嫩梢,被害幼叶呈干枯状,同时分泌蜜露,招致叶片、果实及枝干表面发生烟煤病,由此给芒果种植业带来直接威胁。据室内饲养观察,此虫在海南岛那大地区年发生8代,以成虫在枝、叶上越冬;成虫在田间呈核心分布,一年中以6月份虫口数量最大。建议在一个果园中种植同一品种,合理修枝及喷射20％叶蝉散2000倍液进行防治。

A STUDY ON MANGO LEAF-HOPPER ON HAINAN ISLAND

Mango hopper Idioscopus incertus Baker is one of the most destructive pests of mango trees. It is widely distributed on mango plantations in Hainan Island. The hopper and their nymphs suck sap from the flower buds, tender shoots, young leaves, inflorescences and flowers of tree. All damaged parts will finally dry up and drop. In severe cases, up to 100 per cent of the flowers may be lost due to the hopper infestation. Hopper-infested branches, fruit and leaves normally become sticky as a result of the accumulation of secreted honey-dew on their surface and is accompanied by sooty mould. In Nada, Hainan Island I. incertus has 8 generations per year. Each generation usually takes 18.4-96.6 days. The hopper is present throughout the year, but is abundant only in June. It overwinters on the branches or leaves as adult. Our laboratory and field experiments showed that spraying Mipc(1:2000 dilution) could give good results against this pest. The spraying should be done two to three times from budding to flowering and three times during fruit setting, namely in June, July and December.