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一、园田杂草种类及其特性(一)园田杂草种类危害农田杂草种类很多,据非修诺夫报导苏联有杂草2000多种其中有120种寄生性杂草和220种半寄生性杂草。我国的杂草种类据李扬汉教授初步介绍有1000多种;据辽宁省调查,全省园田杂草种类约700种,据科学院北京植物所调查,北京旱田有杂草138种。为了有效防治杂草,掌握杂草发生规律,必须了解杂草发生种类、数量和生物学特性。1.根据杂草防除的需要分类
First, the type and characteristics of garden weeds (a) garden weed species endanger the many types of weeds in the farmland, according to non-Tronov reported that the Soviet Union there are more than 2,000 kinds of weeds there are 120 kinds of parasitic weeds and 220 kinds of semi-parasitic Weeds. According to Professor Li Yanghan’s preliminary introduction, there are more than 1,000 kinds of weeds in China. According to the survey in Liaoning Province, there are about 700 species of weeds in the park. According to the survey conducted by the Beijing Academy of Sciences, there are 138 weeds in the drylands in Beijing. In order to effectively control weeds, weed grasping laws, we must understand the occurrence of weeds, the number and biological characteristics. 1. According to the needs of weed control classification