香蕉园斜纹夜蛾幼虫的空间分布格局和抽样技术

Spatial Distribution Pattern and Sampling Technique of Spodoptera litura Larvae in Banana Parks

本研究以Iwao直线回归方程和Taylor幂法则,结合3种常用聚集度指标,对香蕉园斜纹夜蛾低龄(1~2龄)、中龄(3~4龄)和高龄(5~6龄)3个龄期幼虫进行空间分布分析。结果表明:香蕉园斜纹夜蛾幼虫的空间分布型与幼虫龄期密切相关,且随着虫龄的增长,其聚集强度逐渐减弱;1~4龄幼虫空间分布格局为聚集分布,个体间相互吸引,其聚集强度随密度的增大而增大;5~6龄幼虫空间分布型由聚集分布逐渐趋向于均匀分布,且个体间存在相互排斥。在此基础上,以中龄幼虫为依据,建立了香蕉园斜纹夜蛾幼虫的最适理论抽样公式n=(t^2/D^2)(1.978/m+3.5119)和最佳序贯抽样公式T(n)=nm0±1.96√n(1.978m0+3.5119m0^2)。

The Iwao linear regression equation and Taylor’s power law,three kinds of aggregation indexes were used to analyze the spatial distribution of Spodoptera litura larvae in banana parks in three stages:low age(1-2),middle age(3-4)and old age(5-6).The spatial distribution pattern of S.litura larvae was correlated with the larval age,and the aggregation intensity decreased with the increase of larval age.The spatial distribution pattern of 1-4 instar larvae was aggregation distribution,and the aggregation intensity increased with the increase of density.The spatial distribution pattern of 5-6 instar larvae gradually tended to uniform distribution from aggregation distribution,and there was mutual exclusion between individuals.The optimum theoretical sampling formula of S.litura larvae in banana parks was established n=(t2/D2)(1.978/m+3.5119)and the best sequential sampling formula T(n)=nm0±1.96√n(1.978m0+3.5119m0^2).