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一、中国棉虫的地区分布特征 依据棉花栽培的自然环境条件,棉花栽培工作者把我国划分为5个棉区:(1)黄河流域棉区;(2)长江流域棉区;(3)辽河流域棉区;(4)西北内陆棉区;(5)华南棉区。 棉虫的发生与其周围的自然条件有不可分割的关系,现在根据5个棉区的自然条件,分别讨论棉虫发生的特征。 1.黄河流域棉区 本棉区北部以长城为界,东自
I. Characteristics of Regional Distribution of Cotton Insects in China According to the natural environmental conditions of cotton cultivation, cotton growers divide our country into 5 cotton areas: (1) cotton area in the Yellow River basin; (2) cotton area in the Yangtze River valley; (3) Basin cotton area; (4) Northwest inland cotton area; (5) South China cotton area. The occurrence of cotton insects and its surrounding natural conditions are inseparable relationship, now based on the natural conditions of five cotton areas, respectively, discuss the characteristics of cotton insects. 1. The Yellow River cotton area The northern cotton area to the Great Wall as a boundary, east from