橘全爪螨种群空间分布与危害

Population Spacial Distribution and Harm of Panonychus citri

通过理论分布的适合性检验、空间格局指标分析,对橘全爪螨(Panonychus citri McG)在温州蜜柑上的空间分布特征、动态与危害进行了系统研究。结果表明,橘全爪螨田间种群分布符合负二项分布,低密度下偶尔符合Neyman A分布。空间分布的基本成分为疏松的个体群,个体群内成员间的分布为随机分布,个体群间呈聚集分布,聚集强度随种群密度的变化而变化,种群低密度下的聚集主要由环境因素引起,高密度下的聚集与该螨自身生物学特性有关。当田间种群数量达到某一危害级别时,相应级别的危害空间容积不超过总体空间的30%,相应的田间药剂防治面积也不应超过总面积的30%。

The spacial distribution pattern,population dynamics and harm of Panonychus citri McG on citrus tree were studied by test of theoretical distribution and analysis of spacial pattern indexes.The results showed that the population distribution of the mite suits with Negative-binomial distribution in citrus garden,and fits with Neyman distribution-A in lower population density too.The spacial distribution pattern presents loose colonies,in which distribution of the colonies is aggregated and the individuals in the colonies show random distribution.The aggregation intensity of population distribution is changing with changes in the mite population density.The aggregation in low density population is caused by environmental factors;and in highdeasity population it is concerned with their biological activities.When the population density a certain up to a certain harm grade,the spacial volume reaching and outstripping this harm level is not over 30% of the total space in citrus garden,accordingly,the area sprayed with insecticides for controlling the harmful mite should not be over 30% of all the area in the field.