主要栽培因子对小麦赤霉病的定量效应研究

本文采用二次回归通用旋转设计,研究了播期(X_1)、密度(X_2)和起身期施氮量(X_3)对小麦赤霉病穗腐的定量效应,建立了黄熟期病指(y)回归模型: y=17.68800-4.50047x_1-0.68735x_2+0.62739x_3-0.28125x_1x_2-1.75000x_1x_3+3.90625x_2x_3-0.34622x_1~2-0.92066x_2~2-1.67185x_3~2并对模型进行解析。结果表明,各栽培因子对赤霉病穗腐病指的效应为播期>密度>氮肥;两因子交互效应为:密度与氮肥互作(x_2x_3)>播期与氮肥互作(x_1x_3)>播期与密度互作(x_1x_2)。其中,播期(x_1)密度与氮肥互作(x_2x_3)对病指的影响均达0.05显著水平。最后对回归模型进行仿真优化,提出控制赤霉病穗腐发生程度的优化栽培方案。

Quantitative Effect of Main Cultural Factors on Wheat Scab.

In this paper, the quantitative effect of the time of sowing (x_1),density of sowing (x_2)and nitrogenous fertilizer (x_3) on the disease index of wheat scab caused by Gibberella zeae was studied by applying the general and rotational regression design with three factors and five levels. According to the data obtained, a mathematical model of the disease index(y) has been built through computation in electronic computer as follows: y=17.68800-4.50047x_1-0.68735x_2+0.62739x_3-0.28125x_1x_1-1.75000x_1x_3+3.90625x_2x_3-0.34622x_1~2-0.92066x_2~2-1.67185x_3~2 (-1.682≤x_1≤1.682). The result of analysis of the model showed that the effect of the time of sowing(x_1) and the interaction effect of density and nitrogenous fertilizer (x_2x_2)were all statistically significant. As a result of the optimization of the model, a scheme of cultural measures for the control of wheat scab was proposed.