摘要
从7个水稻品种纹枯病的严重度(病情指数)与产量损失之间的关系中,找出病斑扩展到稻株倒4叶时(病指40以内)的中抗品种,一般可以不用药剂防治;但病斑扩展至倒3叶(病指超过40)时,减产明显,需用药剂控制.且应掌握在病斑达到倒4叶(病指40)时用药.
By analysing the relationship between disease severity (disease index Dl) and yield loss caused by rice sheath blight on single shoots of 7 cultivars and the effect of controling sheath blight on 4 moder-ately resistant cultivars in field at different locations, it was found that lesions on the 4th leaf from top (DI<40) did not significantly reduce the yield of moderately resistant cultivars. But as the lesions de-veloped up to the 3rd leaf from top, the yield was markedly reduced and chemical control was neces-sary.
In the case of susceptible cultivars, chemical control should be applied when lesions appeared on the 4th leaf from top (DI<40). This was the best time for sheath blight control.
出处
《江苏农业学报》
CSCD
1992年第2期36-39,共4页
Jiangsu Journal of Agricultural Sciences
关键词
水稻
纹枯病
品种
防治
Rice sheath blight
Cultivar
Disease control
