摘要
研究结果表明，杂草株高、干重指数越大，危害期越长，对小麦产量影响越大，损失越严重。杂草相对株高干重积与危害期对小麦产量及成穗数、穗粒数、千粒重呈极显著负相关；与产量损失率呈极显著“Ｓ”型生长曲线正相关，杂草防除经济阈值为株高干重积１０２．１ｍｇｍ－２（混合密度为１５～２０株／ｍ２）；危害临界期为小麦拔节前。并建立了混生杂草对小麦危害损失关系数学模型。
The research results showed that the height,index and harm period of weeds could strongly affect the yield of wheat.The greater they were,the more severe the loss of yield was.The relative weed height,dry weight,and the harm period had a remarkable negative relationship with wheat yield, ears/hm 2, grains/ear and weights/1000 grains,while they showed a remarkable positive relationship to the rate of wheat yield loss.A simulated equation of weeds to wheat yield loss was established in this paper.The economic threshold for weed control was 102.1 m·g·m -2 of the product of height and dry weight (15-20 plants/m 2 weed density).The critical harm period was just before jointing stage.
出处
《西北农业大学学报》
CSCD
北大核心
1998年第6期70-74,共5页
Journal of Northwest Sci-Tech University of Agriculture and Forestry（Natural Science Edition)
