CAJ | 학술논문

　　霜霉菌是一种在十字花科作物中寄主范围很广的专性寄生菌。本研究综合运用病菌形态学观察、病菌致病性测试和rDNA-ITS序列分析三种方法对北京地区的大白菜和甘蓝寄生霜霉菌进行比较，以期发现二者的进化关系。结果显示：两种病原菌在形态学上没有明显区别；但是对大白菜的致病力具有显著差异：大白菜霜霉菌对大多数参试的大白菜材料具有致病性，而甘蓝霜霉菌只是诱导大多数大白菜材料产生过敏反应，对个别易感大白菜材料具有较弱致病力；将rDNA-ITS序列提交至NCBI，大白菜和甘蓝霜霉菌的rDNA-ITS序列登录号分别为JF975613和JF975614，序列比对发现二者的序列一致性高达99.59%；利用19个十字花科霜霉病菌的ITS序列构建系统进化树，结果表明二者与寄生在甘蓝和甘蓝型油菜上的霜霉菌以100%的支持率聚在同一分支。
　　상매균시일충재십자화과작물중기주범위흔엄적전성기생균。본연구종합운용병균형태학관찰、병균치병성측시화rDNA-ITS서렬분석삼충방법대북경지구적대백채화감람기생상매균진행비교，이기발현이자적진화관계。결과현시：량충병원균재형태학상몰유명현구별；단시대대백채적치병력구유현저차이：대백채상매균대대다수삼시적대백채재료구유치병성，이감람상매균지시유도대다수대백채재료산생과민반응，대개별역감대백채재료구유교약치병력；장rDNA-ITS서렬제교지NCBI，대백채화감람상매균적rDNA-ITS서렬등록호분별위JF975613화JF975614，서렬비대발현이자적서렬일치성고체99.59%；이용19개십자화과상매병균적ITS서렬구건계통진화수，결과표명이자여기생재감람화감람형유채상적상매균이100%적지지솔취재동일분지。
The oomycete Hyaloperonospora parasitica (Pers. ex Fr.) is an obligate biotroph infecting a wide range of host species in the family Cruciferae. In this study, the pathogens parasiting on Chinese cabbage (Brassica rapa ssp. pekinensis) and cabbage (B. oleracea) in Beijing area were analysed by morphological characteristics, pathoge-nicity test and the internal transcribed spacer (ITS) sequence of nuclear ribosomal DNA. The two isolates showed morphologically similar on conidiophores and branches, but significant difference in pathogenicity. The rDNA-ITS sequences of the pathogens parasiting on Chinese cabbage and cabbage were submitted to GenBank. The accession numbers were JF975613 and JF975614, respectively. Sequences alignment indicated that a very high similarities of 99.59%was gotten between the two rDNA-ITS sequence. 19 Hyaloperonospora isolates from Cruciferae were used for phylogenetic tree construction. JF975613 and JF975614 were closely relative with Hyaloperonospora brassicae parasiticaing on B. napus and B. orleace with hundred percent support rate.