甘肃小麦禾谷孢囊线虫rDNA-ITS和28S rDNA-D2/D3区序列特征及ITS-RFLP分析

禾谷孢囊线虫是危害禾谷类作物的重要病原,严重威胁我国小麦主产区的小麦产量和品质。利用通用引物对甘肃、河南、安徽禾谷孢囊线虫群体28SrDNA-D2/D3区和rDNA-ITS区进行PCR扩增和序列测定,利用UPG-MA方法分析了甘肃省7个种群、河南1个种群、安徽1个种群的禾谷孢囊线虫群体D2/D3区和ITS区的系统发育关系;用9种限制性内切酶对7个甘肃禾谷孢囊线虫群体的rDNA-ITS区进行了RFLP分析。结果表明:中国甘肃的禾谷孢囊线虫rDNA-D2/D3区片段长度约为780bp,rDNA-ITS片段长度约为1040bp。7个甘肃禾谷孢囊线虫群体、1个河南安阳群体、1个安徽蚌埠群体的D2/D3区和新西兰的H.aucklandica群体亲缘关系很近;其ITS区同澳大利亚的H.australis、北京通州的H.avenae(AY148382)的亲缘关系很接近。RFLP分析表明,9种限制性内切酶酶切禾谷孢囊线虫群体的rDNA-ITS共产生了22个酶切片段,不同酶切的RFLP分布型在7个种群间没有差异。甘肃省禾谷孢囊线虫群体的rDNA-ITS区具有高度的保守性,与中国的C型群体相近,但不同于欧洲的A型群体和印度的B型群体。这是首次报道甘肃CCN种群分子特征。

Sequence and RFLP analysis of rDNA-ITS and 28S rDNA D2/D3 regions of Heterodera avenae on wheat from Gansu Province in China

Cereal cyst nematode (CCN), as an important pathogen of cereal crops, has occurred in a number of wheat growing areas in China. Amplification of 28S rDNA D2/D3 and rDNA ITS regions of Heterodera avenae (CCN) populations collected from Gansu, Anyang county of Henan and Bangbu county of Anhui in China, yielded a fragment of 28S rDNA D2/D3 with the length of approximately 780 bp and one fragment of rDNA ITS of approximately 1 040 bp. The results of D2/D3 and ITS sequences analysis and alignment showed that they were clustered in the same group. A total of 22 scored fragments were obtained from ITS PCR RFLP of CCN populations collected from Gansu. The 9 restriction enzymes produced identical restriction profiles for the population of Gansu. 28S rDNA D2/D3 and rDNA ITS analysis and ITS RFLP analysis showed that 7 populations of Gansu Province might be type C of H. avenae, different from type A of European populations and type B of Indian populations.