氮、磷、钾不同施肥水平下的水稻纹枯病的危害模型的研究

Study on Harming Model of Rice Sheath Blight Under the Condition of Different of N、P and K

采用正交区组二次回归旋转组合设计建立了氮、磷、钾不同施肥水平下的水稻纹枯病病情指数及产量损失率模型；对模型的效应分析结果表明：降低施氮量是控制纹枯病大发生和减少纹枯病引起的产量损失率的最主要的措施，降低的具体水平应根据产量水平和历年的发病情况而确定；适当增加施磷、钾量有利于控制水稻纹枯病，但施钾量超过一定的水平反而有利于水稻纹枯病的发生，因此施钾量不应超过９３．５ｋｇ／ｈａ．

With the rotary socirty of the secondary regression of orthogonal block design, state index of the rice shealth blight and rate of waste model was established under the condition of different fertilizer levels on N、P and K. Result of models effect analysis revealed that reducing amount of nitrogen was the main measure to control rice sheath blight infected in large area and reduce the rate of yield waste leaded by rice sheath blight. Actual level of reducing nitrogen ought to be auording to yield level and the state of illness over the years. Improving P、K properly was benefit to reduce rice sheath blight, but if K was above certain level, it would be benefit to rice sheath blight happen in a large area. So K should not be above 93.5kg/ha.