摘要
潜根线虫(Hirschmanniella spp.)是一类寄生于水稻根部的重要病原线虫,在我国多个省份和地区皆有分布,然而江苏稻区有关该线虫发生和危害鲜有报道。从江苏省农科院水稻实验田采集的水稻根部分离到大量潜根线虫,利用光学和扫描电镜显微观察确定所分离到的线虫优势种群为细尖潜根线虫(Hirschmanniella mucronata),de-Man形态学数据显示江苏分离群体与其他已报道的H.mucronata分离群体具有一定差异,但基本处于标准模式值范围。分别对ITS-rRNA、28S rRNA D2-D3扩展区、18S rRNA、细胞色素氧化酶c亚基I(COI)和热激蛋白90(Hsp90)序列进行PCR扩增,新获得的H.mucronata ITS序列与中国台湾和比利时分离群体具有高度相似性,同时比较各分离群体的ITS1、5.8S和ITS2序列碱基变异,显示我国江苏、台湾和比利时群体差异最小。基于28S rRNA D2-D3扩展区、18S rRNA和ITS-rRNA序列构建的贝叶斯和最大似然进化树将潜根线虫划分为3个进化分支,与已报道的其他H.mucronata种群共同位于第二分支。
Rice root nematode Hirschmanniella spp. spreads globally and has been found in many provinces re- gions of China. However, less report has recorded this kind of threatening nematode in Jiangsu province of China. In the present study, we isolated numerous Hirschmanniella spp. from the rice roots in the paddy field, located in Nanjing, Jiangsu province. Based on the external morphology and morphometrics, we determined that Hirschmanniella mucronata was the dominant species in all nematode population from the infected root tissues. Although some morphometrics of H. mucronata varied from the descriptions of other known isolates and the type specimens, most of morphometric data were within the reference value range. The newly identified H. mucronata was highly similar with the isolates from Taiwan and Belgium, based on the ITS-rRNA sequences and the nucleotide variation in ITS, 5.8S rRNA and ITS2. The results of the phylogenetic analysis based on the sequences of the D2-D3 expansion regions of the 28S, partial 18S rRNA and ITSI-rRNA genes, revealed three concordant clades in the genus Hirschmanniella, thus these molecular makers provide accurate species identification and assessing phylogenetic relationships within Hirschmanniella genus.
出处
《植物病理学报》
CAS
CSCD
北大核心
2016年第4期474-484,共11页
Acta Phytopathologica Sinica
基金
国家自然科学基金资助项目(31401728)
江苏省博士后科研资助计划(1302110B)
