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80年代以来,大面积推广麦田化学除草,对减轻杂草危害,促进三麦增产发挥了显著作用。但麦田草害,尤其是恶性杂草看麦娘和日本看麦娘仍是三麦增产的一大威胁。据武进县调查,1991年夏收三麦91.88万亩,看麦娘发生I级面积占63.9％,Ⅱ级而积占17.6％,Ⅲ级面积占7.8％,Ⅱ、Ⅲ级合计为25.4％。按1981年损失率测定结果计算,约减产1000多万千克,即相当于全县三麦产量的5％。(一)看麦娘严重发生的主要原因1.秋播作物布局有利于杂草连续繁殖。目前秋播作物基本无绿肥,多年小麦与水稻连作,看麦娘种子能够充分成熟脱落田间,导致看麦娘基数迅速提高。2.大面积免、少耕种麦对早发大草处置不力。以往耕翻播种可将播前已出大草和正在萌
Since the 1980s, large-scale popularization of wheat field chemical weeding has played a significant role in alleviating the weed hazards and boosting the yield of three wheat. However, crop damage, especially the weeds see Alyson and Japan to see the mother is still a big threat to increase the yield of three wheat. According to Wujin County survey, 91.88 million mu of Sanmai were collected in the summer of 1991, 63.9% of Grade I area, 17.6% of Grade II area, 7.8% of Grade III area and 25.4% of Grade II and III were seen. According to 1981 loss rate measurement results, about cut more than 1000 million kilograms, which is equivalent to the county three wheat production of 5%. (A) to see the main reason for the occurrence of Amanita 1. Autumn sowing crop layout conducive to continuous breeding of weeds. The current autumn crop basically no green manure, perennial wheat and rice continuous crop, see Amanita seed mature and fall off the field, resulting in the rapid growth of Maiden base. 2. A large area of free and less cultivated wheat on the early grasses ineffective. In the past plowing and sowing can sow before the grass and are adorable