小麦孢囊线虫江苏群体的形态学与分子特征鉴定

【目的】明确小麦禾谷类作物孢囊线虫（cereal cyst nematodes，CCN）江苏群体的种类组成及群体间遗传变异情况，为抗病品种的选育、利用以及病害综合防治提供依据。【方法】对江苏省的13个代表性CCN群体进行孢囊、阴门锥和2龄幼虫的形态观察和形态测计并与相似种进行比较；PCR扩增上述群体的rDNA-ITS区并克隆测序，构建基于ITS序列的系统发育进化树。【结果】通过形态观察和形态测计值的比较，所测定的江苏群体均与已报道的禾谷孢囊线虫（Heterodera avenae）中国群体的测计值相接近；系统进化关系分析显示CCN江苏群体、国内其它地区以及国外禾谷孢囊线虫群体均处于同一大的进化分子簇，且国内和国外群体分别处于不同的进化分支。【结论】所测定的13个江苏省CCN代表性群体均为禾谷孢囊线虫，各群体间形态及ITS序列变异较小，江苏省目前尚未发现菲利普孢囊线虫（H. filipjevi）。

Morphological and Molecular Identification of Cereal Cyst Nematodes on Wheat from Jiangsu Province of China

【Objective】The objective of this study is to understand the species of cereal cyst nematodes (CCN) from Jiangsu Province and their genetic relationships, and to provide valuable information for screening resistant wheat cultivars, plant breeding and integrated control of the disease. 【Method】 The morphology and morphometrics for cyst, vulval cone and second stage juvenile were characterized for 13 typical Jiangsu populations. The ITS regions of ribosomal DNA were amplified and the PCR products were sequenced. A phylogenetic tree was constructed based on the ITS sequences.【Result】The results demonstrated that 13 Jiangsu populations were similar with those described populations of Heterodera avenae by comparing the morphological characters and morphometric data. The phylogenetic tree revealed that the Jiangsu populations were grouped with domestic and abroad populations of H. avenae into a big branch, which could clearly separate Chinese populations from foreign populations.【Conclusion】All the studied CCN populations from Jiangsu Province were identified as H. avenae. The variations in morphological characters and ITS sequences among different Jiangsu populations were very small. The status of H. filipjevi in Jiangsu Province is unknown.