Pokharel Ramesh R, Abawi George S, Zhang Ning, Duxbury John M, Smart Christine D
Department of Plant Pathology, NYSAES, Cornell University, Geneva, NY 14556 Department of Crop and Soil Science, Cornell University, Ithaca, NY 14853.
J Nematol. 2007 Sep;39(3):221-30.
Thirty-three isolates of root-knot nematode were recovered from soil samples from rice-wheat fields in Nepal and maintained on rice cv. BR 11. The isolates were characterized using morphology, host range and DNA sequence analyses in order to ascertain their identity. Results indicated phenotypic similarity (juvenile measurements, perennial pattern, host range and gall shape) of the Nepalese isolates with Meloidogyne graminicola, with minor variations. The rice varieties LA 110 and Labelle were susceptible to all of the Nepalese isolates, but differences in the aggressiveness of the isolates were observed. Phylogenetic analyses based on the sequences of partial internal transcribed spacer (ITS) of the rRNA genes indicated that all Nepalese isolates formed a distinct clade with known isolates of M. graminicola with high bootstrap support. Furthermore, two groups were identified within the M. graminicola clade. No correlation between ITS haplotype and aggressiveness or host range was found among the tested isolates.
从尼泊尔稻麦田地的土壤样本中分离出33株根结线虫，并在水稻品种BR 11上进行保存。为确定其身份，利用形态学、寄主范围和DNA序列分析对这些分离株进行了特征鉴定。结果表明，尼泊尔分离株与禾本科根结线虫在表型上相似（幼虫测量、多年生模式、寄主范围和虫瘿形状），但存在细微差异。水稻品种LA 110和Labelle对所有尼泊尔分离株均易感，但观察到分离株在侵染力上存在差异。基于核糖体RNA基因部分内转录间隔区（ITS）序列的系统发育分析表明，所有尼泊尔分离株与已知的禾本科根结线虫分离株形成一个具有高自展支持率的独特分支。此外，在禾本科根结线虫分支内鉴定出两个组。在所测试的分离株中，未发现ITS单倍型与侵染力或寄主范围之间存在相关性。
