枣麦间作枣园主要蚧虫复合种群结构及生态位

为了有效地控制枣树蚧害，2002年在太谷地区对枣麦间作枣园的康氏粉蚧(Pseudococcus comstock Kuwane)、日本蜡蚧(Ceroplastes japonicus Green)和梨园蚧(Quadraspidiotus perniciosus Comstock)的复合种群结构及其生态位进行了系统研究.结果表明，在枣树发育早期，3种蚧虫分布范围主要在下、中部的东、南方位，康氏粉蚧的时空二维生态位的宽度较大，是该时期的优势种.到中期3种蚧虫复合种群的分布聚集在树冠上部的西、北方位，时 空二维生态位的宽度以日本蜡蚧较大，种间相似程度和竞争不明显.后期3种蚧虫的复合种群结构在各部位的各个方位的分布无明显差异，但梨园蚧的虫口密度较大，日本蜡蚧在生态位上占据较大的空间.与枣树发育的中期相比，3种蚧虫复合种群结构的相似性与种间竞争系数的平均值要小.蚧害预防应早期控制康氏粉蚧，中期调治3种蚧虫的危害，后期应采取措施压低越冬虫源.

Population structure and niche of main scale insects in jujube orchards intercropped with wheat

To effectively control the scale insects in jujube orchards,a field study was made on the population structure and niche of Pseudococcus comstock Kuwane,Ceroplastes japonicus Green and Quadraspidiotus perniciosus Comstock in the jujube orchards intercropped with wheat in Taigu area of Shanxi Province.The results showed that at the early development stage of jujube trees,these three kinds of scale insects mainly distributed on the southeast direction of the lower and central parts of the tree crown,and P.comstock was the dominant species,with a wider breadth of two-dimensional temporal-spatial niche than the other two scale insects.At the mid-stage of jujube trees development,these scale insects mainly distributed on the northwest direction of the upper part of the tree crown,C.japonicus had a wider breadth of two-dimensional temporal-spatial niche than the other two scale insects,and the niche proportional similarity and interspecific competition of the three kinds of scale insects were not obvious.At the later stage of jujube trees development,there was no significant difference(P>0.05) in the population structure of the three kinds of scale insects on the different parts and directions of tree crown,but the density of Q.perniciosus was bigger,and C.japonicus had a wider breadth of two-dimensional temporal-spatial niche.The average values of niche proportional similarity and interspecific competition of the three kinds of scale insects were smaller(P<0.05) at the later development stage of jujube trees.Therefore,P.comstock should be controlled at the early development stage of jujube trees,all the three kinds of scale insects should be controlled selectively at the mid-stage of jujube trees development,and their overwinterings should be decreased by all means at the later development stage of jujube trees.