摘要
病害系统观察,药剂试验及产量损失测定表明,水稻拨节期病情开始激增,病害朝横纵二方向扩展,此时施药防治效果最佳。腊熟期病情指数与拔节期病丛率或病株率、产量损失率均呈极显著直线相关。根据上述关系,便可由早期(拔节期)病情预测最终(腊熟期)病害严重度及产量损失率,进而依据经济阈值定义,组建了杂交稻和常规稻的四个经济阈值的动态模型,提出了在该地目前生产条件下,杂交稻和常规稻不同产量水平的经济阈值,即拔节期防治的指标,为大面积药剂防治提供了依据。
The jointing stage was the suitable period for chemical control because the disease was started to develop rapidly. The disease index at wax rip was highly related to the percentage of tillers infected at jointing stage. The yield loss was closely correlated with the disease index at wax ripeness stage.
According to analysis of the experimental data, the regression equations of the disease index at wax ripeness stage(X)were dependent on the percentage of infected hills (P_1) or infected tillers (P_2) at jointing stage and the percentge of yield loss (Y) was dependent on the disease index at wax ripeness stage (X) were derived.
On the basis of the regression equations and the definition of economic threshold, the four bynemics models for economic threshold were constituted. The economic thresholds with different yield levels were calculated in the area.
出处
《植物病理学报》
CAS
CSCD
北大核心
1990年第2期153-158,共6页
Acta Phytopathologica Sinica
