广东水稻细菌性条斑病菌致病性分化研究

Study on the pathogenicity diversity of Xanthomonas oryzae pv. oryzicola from Guangdong province

水稻抗病性是寄主与病原物互作的结果,病原菌系的分化研究是抗病资源筛选及抗病育种的前提。研究以水稻品种金刚30、IR24、IRBB21、IRBB14、IRBB5、IRBB4、五山丝苗等为鉴别品种,对来自广东地区72个细菌性条斑病菌菌株进行致病力分化测试,并开展了部分广东主栽品种对广东细菌性条斑病菌优势菌系抗性鉴定。结果表明,广东地区的细菌性条斑病菌菌株致病力分化明显,测试菌株可分为19个致病型,其中优势致病型为C18(SSSSRSS)和C5(SRRRRRS),分别占25%、23.61%;强致病性菌系菌株C17(SSSRSSS)、C18(SSSSRSS)、C19(SSSSSSS)占测试菌株的27.78%,主要分布在广州、惠州、阳春、茂名、新会、广宁、雷州地区。测试18个广东主栽品种中,除新银占对测试的优势菌系C18(SSSSRSS)表现中感,其余的均表现感病。

Rice disease resistance is the result of interaction between host and pathogen.The knowledge of differentiation of pathogenic strains is the prerequisite for disease resistance evaluation and its application.In this study,the rice cultivars including JinGang30,IR24,IRBB21,IRBB14,IRBB5,IRBB4 and Wushansimiao were used as the host differenials.The pathogenicity of 72 bacterial leaf streak strains from Guangdong area had been tested.Some of main varieties from Guangdong were selected for their resistance evaluation with the predominant strain of bacterial leaf streak pathogen.The results showed that the pathogenicity of bacterial streak strains from Guangdong area was obviously diversity.The tested strains could be classified into 19 pathotypes,among which the predomni ant pathotypes were C18(SSSSRSS)and C5(SRRRRRS),accounting for 25%and 23.61%respectively.The strong virulent strains which accounted for 27.78%of the tested strains,including C17(SSSRSSS),C18(SSSSRSS),C19(SSSSSSS),were mainly distributed in Guangzhou,Huizhou,Yangchun,Maoming,Xinhui,Guangning,Leizhou area.Almost of eighteen main varieties from Guangdong were susceptible to the tested strains,except that the Xinyinzhan variety show medium susceptible to the predominant strain of C18.(SSSSRSS).