湖南双季杂交晚稻对细菌性条斑病的田间抗性及条斑病发生动态

为明确湖南双季杂交晚稻品种对细菌性条斑病的田间抗性表现及双季晚稻细菌性条斑病的发生特点，通过2014—2016年连续三年的田间系统调查与统计分析，研究了湖南双季杂交晚稻主栽品种上条斑病的田间发病情况及大田细菌性条斑病的发生流行动态，绘制了条斑病发生动态与进展曲线图。结果表明，12个湖南双季杂交晚稻主栽品种中，仅‘深两优5814’、‘天优3301’、‘欣荣优华占’、‘五优308’等4个品种田间抗性表现较好，其余8个品种包括近年种植面积较大的品种如‘天优华占’、‘广两优2010’、‘威优227’、‘H优518’等均表现易感条斑病，揭示湖南双季杂交晚稻对条斑病的抗性水平整体较低；湖南双季杂交晚稻条斑病的始发期在8月中旬，约8月11—15日间，流行高峰期在9月上中旬。上述研究结果可为湖南双季杂交晚稻生产上适时防治细菌性条斑病提供科学依据与指导。

Field evaluation of bacterial leaf streak resistance of double-cropping late hybrid rice and occurrence dynamics of bacterial leaf streak in Hunan

To explore the field resistance of double-cropping late hybrid rice to bacterial leaf streak (BLS) and its occurrence characteristics in Hunan, by systematic field investigation and statistic analysis from 2014 to 2016, we studied the occurrence of BLS in the double- cropping late hybrid rice fields and monitored the epidemic dynamics in Hunan, and created the curve graphs of occurrence dynamics and progress of BLS. The results showed that among twelve hybrid rice varieties, only four varieties‘Shenliangyou 5814’,‘Tianyou 3301’, ‘Xinrongyouhuazhan’and‘Wuyou 308’had excellent resistance, and the other eight varieties were susceptible to BLS, which suggested that the field resistance of late hybrid rice to BLS in Hunan was very poor as a whole. The beginning phase of BLS appeared in the middle of August, approximately from August 11 to 15 and its epidemic peak periods were in the early and middle of September in Hunan. The above results would provide a scientific basis for timely preventing and controlling BLS of double-cropping late hybrid rice in Hunan.