| In this article, the leaf rollers on local longan and litchi in Guangxi were taken as the objective of study, of which their species, metapopulation structure, dynamic of population, the species their host plants, ecological characters of the dominant species and technique of Integrated control to them etc. were researched. The main results were listed as follows.1) Their species. There were 20 species leaf rollers in parts of longan orchard and litchi orchard in Guangxi and 9 species of them were not reported as a pest on longan and litchi in the past time. 2) Metapopulation structure. Both the diversity indexes and the evenness indexes of metapopulation were lower, but the centrality probability index and the dominant index were higher. The results shown that the distributions of number of the different species weren't even, and a certain species had a very vast amount. The main dominant species was Olethreutes leucaspis Meyrick. 3) The season fluctuation of population in the field. The species fluctuation of them was the pattern of several peaks. The most number of species occurred in March was 15 species, there were 12 species in May, 9 species in April and October, 6-7 species in the rest month. The main species in order were: Olethreutes leucaspis > Argyroploce aprobla > Ebodo cellerigera. The season fluctuation of population of the former was the pattern of several peaks, and the two latters were the pattern of single peak. 4) The species of host plants. We investigated the host plants of leaf rollers, the results shown that their host plants contained many species. Olethreutes leucaspis, Argyroploce aprobla and Ebodo cellerigera were the species of oligophagous, and they only damaged longan and litchi, the rest species were the species of polyphagous. In addition, we firstly discovered that Homona coffearia larvae damaged Zizyphus jujuba (Rhamnaceae), Capsicum frutescens var. conoides (Solaraceae), Amarathus viridwas (Amarathaceae) and Archips eucroca damaged Ilex kudingcha (Aquifoliaceae), Capsicum frutescens var. conoides (Solaraceae), Stephania longa (Menwaspermaceae) and Adoxphyes cyrtosemadamaged Breynia fruticosa (Euphorbiaceae). 5) Ecological characters of the dominant species. Olethreutes leucaspwas was the main dominant species, longan and litchi were its host plants. Its larvae occurred and damaged in litchi orchard, damaged tip rate and larval density in order was: the bottom of tree crown > the middle of tree crown > the top of tree crown. The period for the larger larval amount occurred in longan orchard and litchi orchard in May, July and September, respectively. The even supercooling point of larva and its even freezing point of body fluid were -12.78 C and - 3.88'C, respectively. By the results, we could enrich not only the content of ecological study on this pest insect, but also could forecast the distribution regions and the potential distribution regions of this pest insect by its supercooling point and freezing point of body fluid. 6) Integrated control of them. We investigated the basic situation of test regions and chose pesticides, the results shown that (1) the damaged degree at the different tip period was: summer tip period > fall tip period > spring tip period. There were several main other pest insects occurred and damaged along with leaf rollers in longan orchard and litchi orchard, such as Tessaratoma papillosa, Comegenapsylla sinica, Hypitima longae, Monolepta occifuvwas etc.. (2) There were 7 families, 21 species natural enemies of leaf rollers, Trichogramma dendrolimi was an important parasitic natural enemy of eggs and Ichneumon flies and Chrysalid wasps were the important larval parasitic natural enemies, the egg parasitism rate in July and the larval parasitism rate in June and September were all about 30% . In summer tip period, there were 9 families, 28 species spiders in longan orchard, among them, Salticidae population radio was over 65%. (3) Mimic and Cascade were two kinds of security and efficient pesticides, their effect on leaf rollers was better than severa...
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