Virus Movement Protein Gene Mediated Resistance Against Cucumber Mosaic Virus Infection

Tobacco ( Nicotiana tabacum L.) “NC89” plants were transformed with deletion mutant of cucumber mosaic virus (CMV) movement protein (MP) gene and full_length CMV MP gene, respectively. The transformed plants were analyzed with polymerase chain reaction (PCR), PCR_Southern, Southern and Western blots. R 0 generation of the transgenic plants were inoculated with CMV. Five out of 10 lines of tobacco plants (BMPK) transformed with CMV MP deletion mutant gene showed high resistance to CMV infection and remained symptomless for up to 50 days post_inoculation. In contrast, tobacco plants (BMPR) transformed with full_length CMV MP gene did not show resistance to CMV infection. However, most of the infected full_length CMV MP gene transgenic plants recovered by showing none or very mild mosaic symptoms in 40 days post_inoculation. The results of R 1 generation of the BMPK transgenic plants tested under field conditions showed that all 5 lines of transgenic plants could delay the virus disease development.

A Study of Oxalate-Induced Systemic Resistance of Muskmelon to Squash Mosaic Virus

By treatment with oxalate muskmelon cultivar “Wangwenxiang”, which is sensitive to squash mosaic virus (SqMV), develops systemic resistance to SqMV significantly. The challenge inoculation experiments indicate that the symptom of oxalate treated plants gets much slighter, the virus content is only 4% reduced to. The peroxidase activity increases by five times, three new isoperoxidases are induced, and lignin content increases by 82.9%. These results indicate that oxalate induces systemic resistance of muskmelon to SqMV while it induces increase of peroxidase activity, new isoperoxidases and content of lignin in the plants treated with oxalate.

Study on Graft-induced Resistance to Cucumber Mosaic Virus in Pepper

To introduce CMV resistance to susceptible variety, interspecific grafting between d45-6 (Capsicum annuum) and LS1205 (C. baccatum) was conducted. The graft-progenies, G1 and G1S1 were obtained. Mechanical inoculation with CMV showed that disease index of G1 and G1S1 were significantly decreased, similar to that of the resistant stock. ELISA serological test indicated that resistance of LS1205 and the graft-progenies to CMV was caused by inhibition of virul replication. Further, peroxidase isozymatic analysis revealed that zymotypes of G1 were a summation of those found in the donor plants. This result perfectly fit the theory of gene transformation and reconfirmed the conclusion of mechanism of graft-induced variants.

A novel strategy to enhance resistance to Cucumber mosaic virus in tomato by grafting to transgenic rootstocks

Cucumber mosaic virus（CMV） can infect a wide range of host species. For the lacking of CMV resistant varieties of tomato, RNA interference（RNAi） can be used as a fast and effective method for the generation of transgenic resistant varieties. In this current study, five intron-spliced hairpin RNA（ihp RNA） plant expression vectors aimed at five genes of CMV have been constructed. Transgenic tomatoes were obtained by Agrobacterium tumefaciens-mediated transformation with expression vectors. Highly resistant generations of transgenic plants were employed as rootstocks and grafted onto non-transgenic tomatoes that resulted in the successful transfer of resistance to the scions. Using a novel method of plant cuttings for rootstock propagation, we obtained large quantities of disease-resistant material. Further, this method produces scions that can remain undetectable for transgenic resistance marker genes that may provide novel approaches to evade collective concerns about genetically-modified organism（GMO） biosafety.

Comparative transcriptome analysis reveals differential gene expression in resistant and susceptible tobacco cultivars in response to infection by cucumber mosaic virus

Cucumber mosaic virus(CMV) is one of the most severe viral diseases transmitted by aphids infecting Solanum crops in China, causing great losses of crop yields and income in rural communities.The tobacco cultivars NC82 and Taiyan 8 are closely related but differ in resistance to CMV.NC82 is susceptible to infection and Taiyan 8 is resistant, but the mechanisms underlying this difference in resistance are not clear.In this study, we conducted RNA sequencing to analyze changes in gene expression induced in the leaves of Taiyan 8 and NC82 upon systemic infection with CMV, compared with gene expression in the leaves of mock-inoculated plants.Leaves were sampled at one, three, eight, and 15 days after infection.In total, 3443 and 747 differentially expressed genes were identified in Taiyan 8 and NC82, respectively.Gene ontology and pathway enrichment analyses revealed that the different responses to CMV infection between cultivars were based on microtubulebased processes, pentose and glucuronate interconversions, plant–pathogen interaction,and hormone signal transduction pathways.Genes encoding pathogenesis-related proteins, disease-resistance proteins, lipoxygenase, cellulose synthase, an auxin response factor, and an ethylene receptor showed different expression patterns.The differences in gene expression following CMV infection likely contributed to the different resistance levels of these two tobacco cultivars.The comprehensive transcriptome dataset described here,which includes candidate response genes, will serve as a resource for further studies of the molecular mechanisms associated with tobacco defense responses against CMV.

A Comparative Testing of <i>Cucumber mosaic virus</i>(CMV)-Based Constructs to Generate Virus Resistant Plants

Among the viruses Cucumber mosaic virus (CMV) has been rated worldwide as one of the five most important viruses infecting vegetable species. CMV is a tripartite virus with high sequence variability, classified into three subgroups with 80% to 97% identical nucleotides in their coat protein. Due to the absence of natural resistance CMV is the plant virus with longest history in genetic engineering using pathogen induced approaches. However, the transformation and regeneration for some very important crops like chili is difficult. Therefore it will be an advantage to screen in model plants for gene constructs which might be independent of the target of final transformation and other parameters having an influence on the efficiency of a biotechnological approach. In our study we compared the resistance for all combinations of five different antiviral constructs, two different transformation vectors and two model host plants. From these approaches we identified the most effective construct which might also be applicable to transform eventually chili plants.

Oxalate-induced resistance of muskmelon to WMV-2

The treatment of muskmelon cultivar 'Wangwenxiang', which is sensitive to watermelon mosaic virus-2 (WMV-2), with oxalate increases systemic resistance of the cultivar to WMV-2 significantly. The challenge inoculation experiments indicate that the symptom of ox-alate-treated plant is much slighter than that of control plants and the virus content is only 4%

辣椒抗黄瓜花叶病毒病研究进展

黄瓜花叶病毒(CMV)病是影响辣椒生产的主要病害,是辣椒抗病育种的主攻目标。分子标记辅助选择育种可有效地克服传统育种的缺陷,加速育种进程。分子标记的开发依赖于基础研究,辣椒基因组数据的公布为辣椒抗CMV研究提供了一个新的契机。所以本研究就黄瓜花叶病毒的危害、辣椒抗源材料的筛选和抗性鉴定、抗性遗传规律分析及抗性基因定位等方面进行了总结归纳,为进一步辣椒抗CMV研究和分子标记辅助育种提供一定的理论参考。

应用RNA沉默技术获取抗黄瓜花叶病毒(CMV)和烟草花叶病毒(TMV)转基因烟草

RNA沉默是迄今最为有效的抗病毒策略,利用该策略不但能获得免疫转基因植株,且所得植株不易与其他病毒基因重组或异源包壳、生物安全性较高。将本实验室已构建的携带有烟草花叶病毒(TMV)部分移动蛋白基因(ΔMP)和黄瓜花叶病毒(CMV)部分复制酶基因(ΔRep)反向重复结构的植物表达载体pBIN438-MP-Rep(i/r),用农杆菌浸润法转化普通烟草品种K326,共得196株转化植株,经卡那霉素筛选和PCR检测发现128株为阳性转基因植株;PCR-Southern和RT-PCR分析表明外源基因已整合到烟草基因组并在转录水平上得到表达;ELISA结果显示20.3%的转基因植株对CMV和TMV复合侵染表现免疫性。本结果为利用RNA沉默技术进行植物抗多种病毒育种提供重要数据,为防治其他多种病毒复合侵染提供借鉴。

烟草CMV抗性鉴定及抗性基因的SSR标记研究

本研究以抗黄瓜花叶病毒病的烟草品种铁把子和台烟8号,感病品种NC82和中烟15为亲本,构建F1、F2、BC1代分离群体,并对它们进行CMV的接种鉴定和抗性遗传分析,结果表明铁把子和台烟8号对CMV的抗性是由1对隐性基因控制的。依据混合群体分组分析法(BSA),从F2代群体植株中选取DNA建立黄瓜花叶病毒病的抗病基因池和感病基因池,利用135对SSR引物进行分子标记和分析,得到标记SM1350与来源于铁把子的CMV抗性基因间的遗传距离为8.64cM,标记SM2270与来源于台烟8号的CMV抗性基因间的遗传距离为3.92cM。

多抗PVY、TMV和CMV转基因烟草的培育

【目的】利用RNA介导抗性培育抗多种植物病毒的转基因烟草。【方法】分别以马铃薯Y病毒(PVY)、烟草花叶病毒(TMV)和黄瓜花叶病毒(CMV)全长衣壳蛋白(CP)基因为模板,通过设计PCR引物和亚克隆获得PVYCP3′端长度100bp、TMVCP3′端长度100bp和CMVCP3′端长度200bp的cDNA片段并拼接成嵌合基因,并以此为模板构建反向重复结构嵌合基因的植物表达载体pRHPTC。将pRHPTC通过冻融法导入农杆菌LBA4404,采用叶盘法转化烟草NC89,然后测定转基因烟草对3种病毒的抗性。【结果】经卡那霉素筛选和PCR检测,共获得276株转基因烟草。Southern和Northernblot分析表明,外源基因以不同拷贝数整合于烟草基因组中;不同转基因植株中病毒RNA的积累量存在显著差异。抗病性检测显示:23%左右的转基因植株表现出对3种病毒侵染的抗性。对转基因植株扩繁后代和T1代的抗性分析表明:多病毒抗性表现稳定。【结论】利用RNA介导的抗病毒基因工程可获得同时抗多种病毒的转基因烟草,其抗病性在T0代扩繁植株和T1代植株中得到稳定遗传。

黄瓜花叶病毒衣壳蛋白基因转化辣椒研究

The plant expression vector of the coat protein(CP) gene of cucumber mosaic virus (CMV) BS strain was used to transform three kinds of pepper (Capsicum annuum) tissues (cotyledon, stem and root) by agrobacterium-mediated co-cultivation. 53%-68.4% of the total tissues (639) can be induced to be calli, but only cotyledon calli can be further regenerated to form shoots (regenerated efficiency 39.7%). 70%(42/60) of the putative transformed plants were confirmed to have CP gene in their genomes by Southern blot. The mRNAs and the CP were respectively found in 80% of transgenic plants by Northern blot and DAS-ELISA. 24 of the transgenic plants expressing CP gene of BS strain showed three kinds of resistant level (severe symptom, delay of symptomatic development, no symptom) to infection of CMV-BS and of CMV-P. However, there was distinctly higher resistance to inoculation of CMV-BS than that with CMV-P in these transgenic plants.

辣椒CMV广州分离物的鉴定及辣椒材料抗病性筛选

应用RT-PCR方法从黄瓜花叶病毒广州分离物CMV-GZ中扩增出外壳蛋白基因,并进行测序分析,证明该分离物归属于黄瓜花叶病毒亚组Ⅰ。对45份辣(甜)椒材料进行室内苗期人工接种抗CMV鉴定,结果表明,4份辣椒材料对CMV表现为抗病,21份辣椒材料表现为中抗。结合农艺性状调查结果,筛选出5份抗CMV且农艺性状优良的辣椒材料。

黄瓜花叶病毒辣椒分离株抗性遗传规律的研究

采用４Ｘ ４完全双列杂交方法研究了辣椒对黄瓜花叶病毒辣椒分离株（ＣＭＶ－Ｐ）抗性的遗传规律，研究结果表明，辣椒对 ＣＭＶ－Ｐ的抗性至少受 ４对以上核基因控制，具有数量性状遗传特点；抗性的回交效应显著而正反交效应不显著；辣椒对ＣＭＶ—Ｐ的抗性遗传经检验符合“加性—显性”模型，主要受基因的加性效应影响。群体中抗病基因频率高于感病基因频率。通过自交、回交、系统选择可获得抗病性超亲的系统。抗Ｘ感组合的Ｆ１代很难获得超亲组合，要获得高抗杂交组合需选双亲都高抗的亲本。

植物抗黄瓜花叶病毒基因研究进展

黄瓜花叶病毒(Cucumber mosaic virus,CMV)作为世界十大植物病毒之一,严重危害多种作物的生产。相对于药剂防治和使用转基因品种,利用植物自身的抗性基因培育抗病品种是最为经济有效的CMV防治方法。本文就相关内容从3个方面进行综述:(1) R基因介导的植物抗病毒机制及已克隆的R基因;(2)植物抗CMV的R基因及分子机制;(3)植物中其他抗CMV相关基因的研究。

烟草抗花叶病新品系“转墓因NC89”选育技术的研究

本文报导了国内首例抗烟草花叶病毒（ＴＭＶ）和黄瓜花叶病毒（ＣＭＶ）的转基因双抗烟草新品系的选育方法，获得了具有抗ＴＭＶ和ＣＭＶ的双抗优质新品系。在新品系第４—６代的田间试验中，验证了其抗病毒特性的遗传稳定性；与对照品种ＮＣ８９在农艺性状、品质和烘烤特性等方面进行比较，证明转基因抗病新品系除抗病性显著增强外，其它特性均略优于原ＮＣ８９良种。１９９２年在河南省示范推广６６６７ｈｍ~２，转基因抗病新品系对烟草花叶病的相对控制效果为５０％－７０％，防病增产的经济效益显著。

烟草品种对烟草花叶病毒病和黄瓜花叶病毒病的抗性鉴定

由烟草普通花叶病毒(TMV)和烟草黄瓜花叶病毒(CMV)引致的烟草病毒病是世界烟草主产区普遍发生且危害严重的侵染性病害,每年给烟叶生产造成了重大的经济损失。本文采用温室苗期接种鉴定的方法,对16份烟草种质进行了TMV和CMV的抗病性鉴定。结果表明:不同的烟草品种对TMV和CMV的抗病性存在较大差异。在供试种质中,对TMV表现免疫的有‘牛耳烟’、‘8301’、‘台烟7号’、‘三生-NN’共4份材料;表现抗病的有‘吉烟5号’、‘双抗70’、‘大护脖香’、‘秦烟95’共4份材料;表现中抗的有‘铁把子’、‘中烟15’、‘秦烟98’、‘中烟98’共4份材料;表现中感的有‘NC89’、‘翠碧1号’、‘云烟97’共3份材料;表现感病的只有‘秦烟97’。对CMV表现中抗的材料有1份,是‘铁把子’;表现中感的有‘秦烟95’、‘三生-NN’、‘8301’、‘牛耳烟’、‘翠碧1号’共5份材料;表现感病的有‘秦烟98’、‘云烟97’、‘中烟98’、‘NC89’、‘大护脖香’、‘双抗70’、‘秦烟97’、‘中烟15’、‘台烟7号’、‘吉烟5号’共10份材料。研究发现,‘铁把子’是兼抗这两种病毒病的材料。本研究明确了我国16个烟草品种资源的抗病性水平,为抗耐病品种的利用与品种合理布局提供科学依据,同时为烟草抗病毒病育种的亲本选择提供抗源信息。

表达黄瓜花叶病毒外壳蛋白的转基因番茄抗黄瓜花叶病毒侵染

通过土壤农杆菌(Agrobacterium tumefaciens)介导将黄瓜花叶病毒外壳蛋白(CMV CP)的cDNA成功地引入番茄(Lycopersicon esculentum)植株中,并得到转基因植株。用强致病力CMV株系接种后,表达CMV外壳蛋白的转基因植株表现出对CMV侵染的抗性。转基因植株RI代的抗性基因以接近3:1比例分离。对R_1代接种CMV后,表达CMV CP的植株病症减轻,发病率、病情指数及病毒积累量明显低于对照。病症出现推迟1个多月。

植物与黄瓜花叶病毒互作的研究

植物对病原物的抗性包括由单基因控制的质量抗病性和由多基因控制的数量抗病性两种。作物对黄瓜花叶病毒病(CMV)的抗病性属于数量抗病性,即有多个微效抗性基因同时起作用控制黄瓜花叶病毒病的感染,其中研究最精细的是其数量主基因RCY1,该基因位于拟南芥5号染色体,编码一套具有卷曲螺旋-核苷酸结合位点-富含亮氨酸重复序列(CCNBLRR)结构的抗性蛋白;黄瓜花叶病毒病的外壳蛋白基因与RCY1基因共同作用决定作物对黄瓜花叶病毒病的抗性反应。但是在其它的互作体系中,可能存在另外的诱发子和抗性基因,到目前为止尚无定论。

黄瓜花叶病毒香蕉株系衣壳蛋白转基因烟草的研究

构建了侵染香蕉的黄瓜花叶病毒（ＣＭＶ）两个株系（ＢＳ和ＨＩ）的衣壳蛋白（ＣＰ）基因的植物表达载体，并通过农杆菌共培养法和基因枪法，分别将两个株系的ＣＰ基因转化入了两种烟草植株。其ＣＰ基因转化频率及植株再生率研究结果表明，农杆菌共培养法比基因枪法、土耳其烟比本生烟、农杆菌１：１０倍稀释液比培养原液和１：１００倍稀释液，具有更高的转化频率和植株再生能力。Ｓｏｕｔｈｅｒｎｂｌｏｔ和ＰＣＲ一Ｓｏｕｔｈｅｒｎｂｏｌｔ检测ＣＰ基因整合研究结果表明，在两株系ＣＰ基因转化的各１２株烟草中，各有９株含有各自的ＣＰ基因。Ｎｏｒｔｈｅｒｎｂｏｌｔ分析表明，在各７株转基因植株中，各有５株具有各自ＣＰ基因的ｍＲＮＡ的转录。ＤＡＳ一ＥＬＩＳＡ检测表明，各５株转基因植株中都含有各自株系不等量表达的ＣＰ。用ＨＩ株系进行攻击接种表明，具有ｍＲＮＡ转录和翻译的两株系的各５株转基因植株都显示了较高的抗病水平。