云南省水稻细菌性条斑病菌的致病型划分和水稻抗性资源的鉴定

 为明确云南省水稻细菌性条斑病菌(Xanthomonas oryzae pv. oryzicola, Xoc)的致病力分化以及不同类型水稻品种对Xoc的抗感特性,通过针刺接种法将云南省8个稻区采集的86株Xoc菌株,接种于6个携带不同抗性基因的水稻鉴别品种(IRBB4、IRBB5、IRBB14、IRBB18、IRBB21和IR24)。根据这些菌株在鉴别品种上的毒力差异进行了UPGMA聚类分析,将其划分为9个致病型(Ⅰ型 ~ Ⅸ 型)。其中,Ⅰ型为优势菌群,分布频率为50.5%。对不同稻区的优势菌群进行分析,发现云南省各稻区Xoc的致病型呈多样性分布,以强毒力的Ⅰ型为高频率致病型。选用 Ⅰ 型、Ⅱ 型和 Ⅵ 型代表菌株对云南省的80个主栽和区试水稻品种进行抗性评价,对3个致病型表现抗性的材料比例分别为30.0%、35.0%和57.5%。筛选出9个对3种致病型都表现为抗性的品种,其中“Deyou16”和“Changgui2”表现为高抗。研究结果可为云南省防治水稻细菌性条斑病的水稻区域性布局和抗性品种的利用提供理论依据。

Pathotypes differentiation of Xanthomonas oryzae pv. oryzicola and identification of rice varieties resistant to bacterial leaf streak in Yunnan Province

To identify pathotypes different of Xanthomonas oryzae pv. oryzicola and rice varieties resistant to bacterial leaf streak from Yunnan Province. The virulence levles differentiation of 86 isolates of Xoc collected from 8 rice-growing areas in Yunnan province were identified, by using 6 rice varieties ( IRBB4, IRBB5, IRBB14, IRBB18, IRBB21, IR24) which each containing a single resistance gene. The cluster analysis using UPGMA method to Xoc virulence levels showed that 86 strains were classified as 9 pathotypes I-Ⅸ, Among the 9 pathotypes, the pathotype I is the dominant group and most of the pathotype I strains are SSSSSS disease phenotype. The pathotypes Ⅰ was dominant Xoc pathotype in various rice areas of Yunnan. Further research, resistance evaluation of 80 rice varieties from Yunnan Province to pathotype I strain NO.19, pathotype II strain NO.14 and pathotype VI strain NO.16,only 30.0%, 35.0% and 57.5% exhibited resistance to 3 pathotype strain respectively. 9 rice varieties showed resistance to three pathotype strains, especially Deyou16 and Changgui2 showed high resistance levels, this result will be one of the perfect ways to develop bacterial leaf streak disease resistance breeding.