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节节麦是近年来焦作市小麦田上升危害的恶性杂草。根据2年的系统调查和田间试验结果,明确了节节麦在麦田的空间分布型为聚集分布,提出了田间测报调查取样方法。通过小区试验测定了不同节节麦密度下的小麦产量损失率。经数学模拟,确定了小麦产量损失率与节节麦密度间为双曲线函数关系,数学模型:y=x/(0.737 3+0.0259 3x)。根据Chiang的经济阈值计算公式,确定了河南省焦作市不同小麦产量水平和不同防治水平条件下的节节麦防治指标。
Festival of wheat is in recent years Jiaozuo wheat field rise harmful to the vicious weeds. According to the results of two years of systematic investigation and field experiments, it is clear that the spatial distribution pattern of Arthropod (Arthropod) mongolica in wheat field is aggregated distribution, and the sampling method of field survey and survey is proposed. The yield loss rate of wheat under different wheat densities was determined by plot test. Through mathematical simulation, it was determined that the yield loss rate of wheat and nodularity of wheat were hyperbolic functions. The mathematical model was: y = x / (0.737 3 + 0.0259 3x). According to the calculation formula of Chiang’s economic threshold, the prevention and cure index of Nostoc cultivated in different wheat yield levels and different control levels was determined in Jiaozuo City of Henan Province.