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在北京、烟台地区大田条件下研究了夏玉米田杂草治理的生态经济阈值,建立了夏玉米产量损失率与杂草密度的关系。结果表明,杂草与夏玉米的竞争随其密度增加而加剧,夏玉米产量逐渐下降,当杂草密度达到200株/m~2时,夏玉米产量损失率达53.07％。华北地区夏玉米田杂草治理的生态经济闽值为4.21～6.91株/m~2,即当杂草密度低于生态经济阈值时,对玉米产量的影响很小,可任其生长;高于生态经济阈值时则应及时有效地防治。
Under the field conditions of Beijing and Yantai, the ecological and economic threshold of weed management in summer maize field was studied, and the relationship between yield loss rate of summer maize and weed density was established. The results showed that the competition between weeds and summer maize increased with the increasing of density, and the yield of summer maize decreased gradually. When the density of weed reached 200 plants / m ~ 2, the yield loss of summer maize reached 53.07%. The ecological economic threshold for weed management in summer maize field in North China ranged from 4.21 to 6.91 plants / m ~ 2, that is, when the weed density was lower than the eco-economic threshold, it had little effect on maize yield, Eco-economic threshold should be timely and effective prevention and treatment.