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通过田间试验,研究了小麦条锈病中心病株上夏孢子在风向不变的一段时间内,气流传播的二维空间分布。优用模型 E=exp(A—BD~n)拟合叶面孢子着落量(Z)随距离(D)增加而递减。在试验条件下,以 n=1拟合最好。建立了 A 因初始菌量(S)和平均风速(W)、B 因平均风速而变的预测模型。根据田间病情分布形状推断,孢子的二维分布形状近似椭园形,并可假设抱子与风向垂直的横向分布为正态分布。孢子横向扩散程度受大气稳定度和初始菌量的影响,用椭园率(E)描述孢子的横向扩散程度,用初始菌量和平均风速建立了估计离心率的模型。采用正态分布密度函数与梯度模型 y=A-BD~n[y=Ln(Z)]组建了孢子密度二维空间分布的模型。
Field experiments were conducted to study the two-dimensional spatial distribution of airborne airflow over a period of time during which the summer spores of the stripe rust center of the stripe rust were infected by wind. The optimal model E = exp (A-BD ~ n) fitted foliar spore volume (Z) decreases with increasing distance (D). Under the experimental conditions, n = 1 is the best fit. A predictive model of A due to the initial bacterial volume (S) and the average wind speed (W) and B due to the average wind speed was established. According to the field distribution of the disease inferred that the two-dimensional distribution of spores approximate elliptic shape, and can assume that vertical and horizontal distribution of spores and wind direction of the normal distribution. The extent of lateral spore spread was affected by the atmospheric stability and the initial bacterial biomass. The ellipticity (E) was used to describe the extent of spore propagation. The model of estimated eccentricity was established using initial bacterial counts and mean wind speed. A two-dimensional spatial distribution model of spore density was established by using normal distribution density function and gradient model y = A-BD ~ n [y = Ln (Z)].