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调查结果表明:稻纵卷叶螟的虫苞及幼虫田间分布型属聚集分布。其分布与水稻尽势等环境因素有关。当允许误差D=0.2时,不同幼虫虫口密度(?)下的抽样数量为n=3.7+26.9/(?)。在几种取样方法中以平行线法较好。
The investigation results showed that the field distribution patterns of insects and larvae of C. medinalis were aggregated and distributed. Its distribution and rice and other environmental factors to make the best. When the allowable error D = 0.2, the sampling number under different larval population density (?) Is n = 3.7 + 26.9 / (?). In several sampling methods to parallel line method is better.