STUDIES ON SPATIAL DISIRIBUTION OF LARVAE OFLEAF MINER, Phthorimaea operculellaAND ITS APPLICATION
烟草潜叶蛾幼虫空间分布型及其应用研究

The aggregation indices and Taylor's power law are used to test the spatial distribution of the third generation larvae of leaf miner in the tobacco fields. The results are as follows: The distribution pattern of larvae is aggregative ( negative binomial distribution) . The aggregation dose not change with the densities of population of leaf miner. The larvae are mainly aggregated distribution on the first stratification (four leaves) beneath tobacco plant; aggregated or random distribution on the second stratification; random distribution on the third stratification. Otherwise, the frequency of occurrence are used to estimate population densities of leaf miner. By comparing calculating population densities of the theoretical curves from Wilson's model and Gerrard's model with practical one, it is found that the relationship between them is significant fit. But sampling estimating error of Gerrard's model is less than that of Wilson's. Meanwhile, models of optimization sampling and sequential sampling are obtained by using Taylor's parameters as follows: N = 1.68857 (t/D) 2-090661 and TM = (0/1.68857) -1.10301.n-0.10301