应用细菌磁颗粒RT-PCR检测3种植物病毒

根据细菌磁颗粒对植物病毒颗粒的非特异性吸附作用,建立了一种新的提取植物病毒RNA的方法。利用细菌磁颗粒收集黄瓜绿斑驳花叶病毒、黄瓜花叶病毒和百合无症病毒等3种病毒颗粒,富集分离后,通过高温使其裂解释放出病毒RNA,进行RT-PCR检测。与利用Trizol试剂提取这3种植物病毒的RNA相比,具有操作简单、无毒性,能够显著缩短提取时间。对黄瓜绿斑驳花叶病毒的检测灵敏度验证表明:BMPs-RT-PCR与Trizol-RT-PCR的检测灵敏度相同,均为105倍的植物叶片组织稀释液。     

南方水稻黑条矮缩病毒检测方法的比较

为明确南方水稻黑条矮缩病毒（Southern rice black-streaked dwarf virus, SRBSDV）检测方法的最佳适用范围,对其现有检测方法Real time RT-PCR、RT-LAMP、RT-PCR的灵敏性及特异性进行了比较,并分析了依据SRBSDV单克隆抗体3F1建立的斑点免疫结合印迹（dot immunobinding assay, DIBA）方法对检测植物寄主和白背飞虱Sogatella furcifera Horvth的特异性。结果表明,灵敏性以Real time RT-PCR方法最高,其次为RT-LAMP方法,而普通RT-PCR方法相对较低。这3种方法均可特异性检测SRBSDV植物寄主和白背飞虱;DIBA方法可以满足SRBSDV和水稻黑条矮缩病毒（Rice black-streaked dwarf virus, RBSDV）植物寄主和白背飞虱大量样品的检测,但不能区分SRBSDV和RBSDV。Real time RT-PCR方法实现了短时间内对SRBSDV RNA拷贝数的相对定量;RT-LAMP方法全程恒温反应,无需热循环仪。     

一步RT-PCR检测南芥菜花叶病毒方法的建立

本研究采用Trizol快速提取植物叶片总RNA，通过GeneBank设计特异性引物，并利用一步RT—PCR技术，最终建立了一套比较实用的检测ArMV的方法。该方法对于其它病毒的检测同样具有借鉴意义。     

10种植物病毒的基因芯片检测技术研究

 本研究设计了10种植物病毒和各种对照的探针, 将探针固定在醛基化玻璃片基上制备基因芯片。用常规的Trizol法提取植物总RNA, 根据病毒的外壳蛋白基因或复制酶基因设计特异性引物, 经RT-PCR扩增相应区段并用Cy3-dCTP进行标记。将标记的PCR产物与芯片杂交, 扫描仪对杂交结果扫描, GenePix Pro 4.0软件对杂交图像进行分析。结果表明, 该芯片可以从病毒感染样本中检测到特异性识别信号, 检测灵敏度比RT-PCR高10~100倍, 所以, 基因芯片能对植物病毒作出快速、准确的检测。     

半巢式RT-PCR检测进口大豆中菜豆荚斑驳病毒的研究

 菜豆荚斑驳病毒(Bean pod mottle virus,BPMV)在美国东部和南部的大豆产区广泛分布。该病毒能够造成3%~52%的产量损失并使大豆品质降低,目前我国未见其分布。针对进口大豆种子的植物病毒检测,本文建立了半巢式RT-PCR技术检测BPMV的方法。该方法采用Trizol快速提取大豆种子病毒总RNA,并根据BPMV的外壳蛋白编码基因设计特异性引物,经第一轮RT-PCR和第二轮半巢式PCR扩增,分别得到275 bp和196 bp大小的特异性基因片段。半巢式RT-PCR扩增产物的测序表明,该产物序列与BPMV的外壳蛋白编码基因存在91%~95%的高度同源性。检测灵敏度比较研究显示,DAS-ELISA与RT-PCR的检测灵敏度相近,半巢式RT-PCR的检测灵敏度比这2种方法高出103倍以上。     

烟草环斑病毒和番茄环斑病毒的半巢式RT-PCR检测

烟草环斑病毒(Tobacco ringspot virus,TRSV)和番茄环斑病毒(Tomato ringspot virus,ToRSV)是我国禁止入境的检疫性有害生物。采用半巢式RT-PCR方法对这两种病毒进行了检测,用Trizol快速提取病毒总RNA,并根据TRSV和ToRSV的外壳蛋白基因设计特异性引物,经过第一轮RT- PCR和第二轮半巢式PCR扩增,TRSV样本分别得到359 bp和206 bp特异性片段,ToRSV样本分别得到340 bp和219 bp特异性片段。半巢式RT-PCR扩增产物的测序表明,TRSV产物序列与GenBank中登录的外壳蛋白基因存在88%～97%的同源性,ToRSV产物序列与GenBank中登录的外壳蛋白基因存在96%～100%的同源性。研究显示,DAS-ELISA与RT-PCR的检测灵敏度相近,而半巢式RT-PCR的检测灵敏度比这两种方法高出10~3倍以上。     

齿兰环斑病毒与建兰花叶病毒分子检测研究

齿兰环斑病毒（Odontoglossum ringspot virus,ORSV）与建兰花叶病毒（Cymbidium mosaic virus, CyMV）是严重危害兰科植物的两种主要病毒。本研究根据病毒外壳蛋白基因设计特异性引物,应用ELISA、普通RT-PCR、巢式RT-PCR和免疫捕获RT-PCR4种方法进行了检测研究与比较。结果表明：普通RT-PCR与ELISA方法检测灵敏度相当;巢式RT-PCR检测灵敏度要比普通RT-PCR与ELISA方法高出104倍以上;免疫捕获RT-PCR检测灵敏度介于普通RT-PCR和巢式RT-PCR之间。采用巢式RT-PCR方法对我国台湾进境的蝴蝶兰植株样本检测,1号样本出现与阳性对照一致的特异条带。双向测序分析,扩增产物序列与ORSV外壳蛋白基因具有100％的同源性,表明1号蝴蝶兰样本携带ORSV。     

苹果花叶病毒的RT-PCR检测及其在我国苹果产区的分布

为了开发苹果花叶病毒（Apple mosaic virus,ApMV）田间样本RT-PCR检测方法和揭示我国ApMV的发生情况,以田间染病苹果组织为材料,对ApMV RT-PCR检测体系中总RNA提取方法、反应体系及程序进行了选择和优化,并利用优化的检测方法对我国苹果主产区13个省的23个市（县）ApMV发生情况进行了检测。以RNA提取改良法提取的田间样本总RNA为模板,RT-PCR优化体系的灵敏度达到能够检测15μg田间样本组织中的ApMV,且在果树整个生长发育时期能够检测1年生枝条树皮组织的带毒情况;ApMV在我国普遍发生,13个省的23个市（县）均检测到了ApMV,采集的327个样本带毒率为80.1%,其中未显花叶症状样本205个,ApMV阳性率为68.3%;在23个地区中,只有河北张家口、河南三门峡和陕西白水样本带毒率低于50%。     

北京地区百合无症病毒CP基因的克隆与分析

以感染百合无症病毒(LSV)的百合叶片为材料,提取总RNA为模板,通过反转录聚合酶链式反应(RT-PCR)扩增出856bp大小的LSV CP基因片段.经Blast比对发现,该基因片段与Genbank上发表的ISV CP基因序列(DQ294655.1)同源性为97.31%.由该序列推导出的氨基酸序列与其相似度为98.6%,仅存在某些氨基酸的差异.经过聚类分析表明,该CP基因的氨基酸序列与厦门和兰州分离的病毒遗传距离较近,而与海宁和广州分离的病毒遗传距离较远.     

山东泰安甜樱桃“花叶病”树体症状观察及病毒检测

为了探明山东泰安患有"花叶病"的甜樱桃树体内感染病毒的种类,本研究以嫁接在3种不同砧木上的甜樱桃品种‘红灯’叶片为试验材料,提取植物样本总RNA,采用随机六聚体引物反转录,选取10种甜樱桃病毒作为检测对象,根据各病毒基因组序列设计特异引物,进行RT-PCR检测。结果显示,10种甜樱桃待检病毒中,5种病毒检测结果呈阳性,分别为PNRSV(Prunus necrotic ringspot virus,PNRSV)、PDV(Prune dwarf virus,PDV)、CVA(Cherry virus A,CVA)、CGRMV(Cherry green ring mottle virus,CGRMV)、LChV-2(Little cherry virus-2,LChV-2),各病毒检出率较高。各"花叶病"甜樱桃样品均至少同时感染2种病毒,多病毒复合感染比例较高。     

应用细菌磁颗粒实时荧光RT-PCR检测南瓜花叶病毒

 A novel real-time RT-PCR method, BMPs based real-time RT-PCR which integrated with magne-tic separation technique of bacterial magnetic particles(BMPs), was set up for detection of Squash mosaic virus(SqMV).After SqMV particles in crude sap were concentrated by BMPs, viral RNAs were released and detected by real time RT-PCR.The results indicated that BMPs based real-time RT-PCR was efficient, and the detection sensibility was equivalent to that of the Trizol based real-time RT-PCR, of which Trizol reagent was used for viral RNAs extration.Comparing to Trizol-based method, the BMPs-based method had advantages of simplicity on operation, time saving for RNA extraction and without using noxious organic chemicals.     

应用MNP-RT-PCR方法检测黄瓜绿斑驳花叶病毒

 A novel RT-PCR method integrated with Magnetic Nano Particles (MNP), MNP-RT-PCR, was set up for detection of Cucumber green mottle mosaic virus (CGMMV). After the virus particles in crude sap were concentrated by MNP, viral RNAs were released and were detected by RT-PCR. CGMMV could be detected in as less as 10 ng watermelon leaf materials. Compared with normal RT-PCR, the method decreased the inhibitors of plant material and steps for extracting RNA, and also increased the sensitivity of RT-PCR detection in less time. The method is simple and suitable for quick detection of plant virus in a large number of samples.     

鸢尾黄斑病毒几种PCR检测方法的建立和比较研究

 以带有鸢尾黄斑病毒的烟草叶片为材料,研究建立了IYSV的普通RT PCR、免疫捕获RT PCR和SYBR Green Ⅰ实时荧光RT PCR方法,并比较了几种检测方法的灵敏度。结果表明,DAS ELISA检测灵敏度较低,为1 mg带毒叶片。而各种PCR方法的灵敏度均高于DAS ELISA 100倍以上,其中SYBR Green Ⅰ实时荧光RT PCR检测灵敏度最高,可从0.4 μg的带毒叶片中检出IYSV,而RT PCR的灵敏度为40 μg带毒叶片,IC RT PCR的检测灵敏度是RT PCR的4倍。鉴于DAS ELISA灵敏度较低,建议在用ELISA初筛时,如样品OD405值与阴性对照OD405值之比在2.0左右时需要再用分子方法加以确证,以防漏检。     

Recovery from Cucurbit leaf crumple virus (family Geminiviridae, genus Begomovirus) infection is an adaptive antiviral response associated with changes in viral small RNAs

A strong recovery response occurs in cantaloupe (Cucumis melo) and watermelon (Citrullus lanatus) infected with the bipartite begomovirus Cucurbit leaf crumple virus (CuLCrV). This response is characterized by initially severe symptoms, which gradually become attenuated (almost symptomless). An inverse relationship was detected between viral DNA levels and recovery, indicating that recovered tissues had reduced viral titers. Recovered tissues also were resistant to reinfection with CuLCrV; i.e., recovered leaves reinoculated with the virus did not develop symptoms or have an increased level of viral DNA. In contrast, infection of CuLCrV-recovered leaves with the RNA virus, Cucumber mosaic virus (CMV), disrupted recovery, resulting in the development of severe disease symptoms (more severe than those induced by CMV or CuLCrV alone) and increased CuLCrV DNA levels. Small RNAs with homology to CuLCrV DNA were detected in recovered and nonrecovered tissues; as well as in phloem exudates from infected, but not uninfected plants. Levels of these small RNAs were positively correlated with viral titer; thus, recovered tissues had lower levels than symptomatic tissues. In addition, viral DNA from a host that undergoes strong recovery (watermelon) was more highly methylated compared with that from a host that undergoes limited recovery (zucchini). Furthermore, inoculation of CuLCrV-infected zucchini with a construct expressing an inverted repeat of the CuLCrV common region enhanced recovery and reduced viral symptoms and viral DNA levels in newly emerged leaves. Taken together, these results suggest that recovery from CuLCrV infection is an adaptive antiviral defense mechanism, most likely mediated by gene silencing.     

番茄褐色皱果病毒SYBR Green Ⅰ实时荧光RT-PCR检测方法的建立和应用

根据番茄褐色皱果病毒(tomato brown rugose fruit virus,ToBRFV)外壳蛋白(coat protein,CP)的保守基因序列设计l对特异性引物,建立了基于SYBR Green Ⅰ的ToBRFV实时荧光RT-PCR检测方法,并对其进行了特异性、灵敏度检测,对自然感染ToBRFV的番茄、辣椒...     

水蜡A病毒在呼和浩特市和哈尔滨市紫丁香上的发生及其基因组分子特征分析

为明确侵染紫丁香Syringa oblata并引起褪绿花叶症状的病毒种类及其基因组分子特征,利用透射电子显微镜对分离自呼和浩特市和哈尔滨市的紫丁香病样中的病毒粒子进行观察,并通过小RNA高通量测序和RT-PCR技术对其进行检测分析。结果表明,在紫丁香显症叶片的病毒粗提液中观察到长约600 nm、宽约13 nm的线状病毒粒子。利用小RNA高通量测序和RT-PCR技术从病样中检测到水蜡A病毒（Ligustrum virus A,LVA）,发病率为3.7%。呼和浩特市紫丁香分离物LVA-Sob的基因组序列全长8 525 nt,包含6个开放阅读框,分别编码Rep（1 968 aa）、TGB1（229 aa）、TGB2（107 aa）、TGB3（60 aa）、CP（294 aa）和NABP（119 aa）共6个蛋白。序列一致性分析表明,分离物LVA-Sob与韩国水蜡树分离物LVA-SK的基因组序列一致率高达97.9%,而与我国辽宁省暴马丁香分离物LVA-DX的基因组序列一致率仅为73.6%。在这3个LVA分离物基因组中没有检测到重组事件;基于基因组和cp基因序列的系统发育树显示这3个LVA分离物形成一个分支,并与瑞香S病毒（daphne virus S,DVS）有较近的亲缘关系。