入侵地喜旱莲子草的昆虫群落特征与天敌种类  

Insect Community of Invasive Pest Alternanthera philoxeroides in China

作　　者：李倬锴[1] 王煜[1] 金涛[1] 何俊[1] 王磊[1] 董慧琴[1] 蔡星星[1] 潘晓云[1] 

机构地区：[1]生物多样性和生态工程教育部重点实验室复旦大学生物多样性科学研究所复旦大学生态与进化生物学系,上海200433

出　　处：《陕西林业科技》2008年第4期6-10,共5页Shaanxi Forest Science and Technology

基　　金：复旦大学生命科学学院天目山野外实习计划;国家重点基础研究发展规划(973)项目(2006CB403305);国家自然科学基金项目(30400052)资助

摘　　要："天敌释放"是外来植物成功入侵的重要机制之一。喜旱莲子草(Alternanthera philoxeroides)是一个世界性的外来入侵种,在原产地有多种天敌昆虫。本文初步研究了喜旱莲子草在入侵地的昆虫群落物种多样性、天敌昆虫类型及虫食特征。对生长在天目山低海拔地区的池塘和陆地2类生境中的喜旱莲子草单优势种群落中的昼行性昆虫群落进行了取样调查。采用扫网法捕捉昆虫,并对网捕昆虫鉴定至科;种名没有鉴定,但每科下均为1种。主要结果是:在样地中共捕获昼行性昆虫58头,隶属于5目6科6种。样本数量较多的有,蝗科(40%)、蝇科(22%)和卷蛾科(12%)。除昆虫密度外(1.8头.m-2与4.3头.m-2),水、陆2类生境中昆虫群落的物种丰富度(6和5)、多样性指数(2.25和2.09)和均匀度指数(1.26和1.30)均无明显差异。取食喜旱莲子草的昆虫只有蝗科和卷蛾科各1种。水、陆生境下叶片虫食类型有差异,水生生境中以缘食状或孔洞状为主(蝗虫所食),而陆生生境中以缘食状和透明膜状为主(蝗虫与蛾类所食)。与文献中报道的喜旱莲子草原产地天敌昆虫群落的结果比较可知,入侵中国的喜旱莲子草在天敌昆虫物种丰富度及专化天敌昆虫种类两方面都存在显著的"天敌释放"效应。失去天敌昆虫的"下行"控制作用可能是其成功入侵的重要机制之一。The enemy release hypothesis （ERH） proposes that if a plant introduced into a new region leaves behind some of its herbivores and pathogens, its chances of reproductive success increase, giving exotic plants a competitive advantage in comparison with native plants in the invaded community. Alternanthera philoxeroides （Mart.） Griseb. （Amaranthaceae, alligator weed） is one of the most notorious invasive weeds and has been introduced to the regions with warm to subtropical humid climates worldwide. In native range （South America）, as to species level） were recorded on alligator weed. many as 40 insect species （not all could be identified Five of the 40 species were considered to suppress alligator weed. To investigate the possible role of enemy release in the invasion of alligator weed in China, field surveys of insect community and types of enemy insects associated with A. phiIoxeroides in the lowlands of Tianmu Mountain were conducted. Insects were collected by sweep net. Total 58 insect individuals were collected, which belong to 5 orders 6 families and 6 species. Insects belong to Acridoidea （40%）, Muscidae （22%） and Tortricidae （12%） showed highest occurrence in July. Only two species are enemy insects belonging to Acridoidea and Tortricidae, respectively. The species diversity and dominant species of insect communities from pond and land habitats were not different. Compared with the enemy insect community in Argentina, species diversity in China decreased by 43 in terms of family and by 50% in terms of species. In addition, there is no any specialist insect in China. Loss of the top-down control effects may partially contribute to successful invasion of alligator weed in China.

关 键 词：生物防治 天敌释放 物种多样性 

分 类 号：S451[农业科学—植物保护]