淹水与汕优63白叶枯病发生的关系

采用人工接种法研究了淹水对汕优６３白叶枯病发生的影响。结果表明，稻株发病程度与淹水持续时间的长短有关。淹水２ｄ病情显著加重，当淹水延长到６ｄ以上后，病害反而明显变轻。淹水期间病斑扩展减慢和长时间淹水对汕优６３抗病性的诱导，可能是长时间受淹减轻白叶枯病对汕优６３危害的主要原因。

Influence of Flooding on Incidence of Rice Bacterial Leaf Blight of Shanyou 63

The effect of flooding treatment was studied on the incidence of rice bacterial leaf blight (BLB) in hybrid rice Shanyou 63 by artificial inoculation. The results showed that severity of the disease of Shanyou 63 was related to the period of flooding. Two days of submergence resulted in the most serious incidence of the disease while six days of or longer submergence made the disease incidence lessened. During submergence the lesion expanding of the disease slowed down, and a long period of flood induced the resistance of Shanyou 63 to BLB, which might be the important reason for Shanyou 63 less damaged by BLB after a long period of flooding.