番茄光尾拟短体线虫的形态和分子鉴定  

Morphological and molecular identification of Pratylenchoides leiocauda in tomato

作　　者：李冉 顾建锋 李红梅 张晓梅 王暄 LI Ran;GU Jianfeng;LI Hongmei;ZHANG Xiaomei;WANG Xuan(College of Plant Protection/Key Laboratory of Integrated Management of Crop Diseases and Pests,Ministry of Education,Nanjing Agricultural University,Nanjing 210095,China;Technical Center of Ningbo Customs,Ningbo 315100,China;Xining Vegetable Technical Service Center of Qinghai Province,Xining 810016,China)

机构地区：[1]南京农业大学植物保护学院/农作物生物灾害综合治理教育部重点实验室,江苏南京210095 [2]宁波海关技术中心,浙江宁波315100 [3]青海省西宁市蔬菜技术服务中心,青海西宁810016

出　　处：《南京农业大学学报》2020年第6期1033-1041,共9页Journal of Nanjing Agricultural University

基　　金：中国海关总署科研项目(2020HK161);国家公益性行业(农业)科研专项(201503114);浙江省自然科学基金项目(Y19C140008);宁波市科技创新团队项目(2015C110018)。

摘　　要：[目的]拟短体属线虫(Pratylenchoides spp.)是一类迁移性植物内寄生线虫,从青海长势衰弱的番茄植株根系及根围土样中分离到1种拟短体线虫群体,本文对该群体进行形态学特征鉴定和分子特征分析,旨在为今后拟短体线虫属种类鉴定提供参考依据。[方法]通过形态特征观察和测计值比较,利用贝叶斯法和最大似然法构建拟短体属线虫群体的rDNA 18S、28S-D2/D3以及ITS系统进化树,对青海线虫群体进行种类鉴定。[结果]青海线虫群体形态学特征与光尾拟短体线虫(Pratylenchoides leiocauda)相似,其主要形态特征为:侧线6条;唇区无明显缢缩,唇环3~4个;口针较粗壮,口针基部球宽圆形,明显向后倾斜;食道腺背侧覆盖肠端,覆盖长度为1~2个最大体宽;背食道腺核位于食道腺与肠交接处之前,至少有1个亚腹食道腺核位于肠与食道腺交接处后方;尾圆柱形,末端光滑或有1~3条环纹;雄虫交合刺较长,交合伞较大包裹到尾端。系统进化树显示:青海线虫群体与齿尾拟短体线虫(P.crenicauda)、埃尔祖鲁姆拟短体线虫(P.erzurumensis)以及侧尾拟短体线虫(P.laticauda)等聚类在一大分支上,根据食道腺和雌虫尾端特征可将光尾拟短体线虫与近似种区分开。这些拟短体线虫均与默林线虫科成员亲缘关系较近。[结论]通过形态学特征鉴定和分子特征分析将青海线虫群体鉴定为光尾拟短体线虫,并验证了拟短体线虫隶属于默林线虫科(Merliniidae)这一分类地位,丰富了我国植物寄生线虫的分类学信息。[Objectives]The Pratylenchoides species are migratory endoparasites of plant roots.A Pratylenchoides population was isolated from the roots and rhizosphere soil from weakened tomato plants in Qinghai Province.The Qinghai population was morphologically identified and molecularly analyzed,and the study provides more useful information for the identification of Pratylenchoides species.[Methods]The Qinghai population was identified using the morphological observation and morphometrics comparison.The phylogenetic trees were constructed on basis of rDNA 18S,28S-D2/D3 and ITS sequences using Bayesian and Maximum Likelihood analyses.[Results]The morphological characterizations revealed that the Qinghai population was similar to Pratylenchoides leiocauda.The morphological characters of the population were mainly as follows:lateral field with six incisures;labial region slightly offset from body,having 3-4 annuli;stylet stout,knobs broadly rounded and sloping posteriorly;pharyngeal glands overlapping intestine dorsally for 1-2 times the body width;dorsal pharyngeal gland nucleus located mostly anterior to the pharyngo-intestinal valve,and at least one of the subventral pharyngeal gland nuclei located posterior to the valve;female tail conical,terminus without annulus or having 1-3 annuli;male spicules long,large bursa extending continually to tail terminus.The phylogenetic analysis revealed that the Qinghai population was grouped with P.crenicauda,P.erzurumensis and P.laticauda,as well as other Pratylenchoides species into a big branch.Pratylenchoides leiocauda can be distinguished from other similar Pratylenchoides species by the characters of pharyngeal glands and female terminus.In addition,the Pratylenchoides species had a close relationship with the species from genera of the family Merliniidae.[Conclusions]The Qinghai population was identified as P.leiocauda based on morphological identification and molecular analysis.The taxonomical status of genus Pratylenchoides belonging to the family Merliniidae was also verifie

关 键 词：光尾拟短体线虫 形态特征 形态测计值 系统进化 种类鉴定 

分 类 号：S41-32[农业科学—植物保护] Q19[生物学—普通生物学]