烟草赤星病危害烤烟产量产值损失测定

在烤烟生长中后期 ,应用40%菌核净500倍液人为控制烟草赤星病发生程度 ,形成不同危害梯度 ,以研究烟草赤星病对产量产值的影响。经试验分析 ,建立数学模型。中上等烟产量损失率(Y₁)与病情指数(X)的关系式:Y₁=0.1516+1.2824X;产值损失率(Y₂)与病情指数(X)的关系式:Y₂=0.3239+0.9831X。     

The fate of imidacloprid in tobacco smoke of cigarettes made from imidacloprid-treated tobacco

The residues and metabolites of radiolabelled imidacloprid [1-(6-chloropyridin-3-ylmethyl)-N-nitroimidazolidin-2-ylideneamine], formulated as a wettable powder containing 250 g kg^-1 active ingredient diluted with water and administered to tobacco plants, were studied in sidestream and mainstream smoke, in the ash and butts after smoking cigarettes. An almost complete recovery of radioactivity (93·5%) was achieved. The highest amounts of radioactivity were found in the butts and sidestream smoke. The two dominant compounds identified after smoking were unchanged parent compound and carbon dioxide. A total of 76% of the recovered radioactivity was identified. © 1998 SCI.     

A survey of tobacco viruses in tobacco crops and native flora in Greece

The most important tobacco producing areas in Greece were surveyed for virus presence, from 1997 to 2000. Tobacco seedlings or plants showing virus-like symptoms were randomly collected from seedbeds or fields, respectively, and tested by ELISA, and/or mechanical inoculation onto indicator plants. Potato virus Y (PVY), Cucumber mosaic virus (CMV) and Tobacco mosaic virus (TMV) were detected in all sampling areas, with TMV mainly found in oriental varieties. Tomato spotted wilt virus (TSWV) consisted a serious endemic virus in Northern Greece (Thrace, Central and Eastern Macedonia), whereas Alfalfa mosaic virus (AMV) was mainly found in regions, where alfalfa was cultivated in the vicinity of tobacco crops. Eggplant mottled dwarf virus (EMDV) was detected in several areas but always in very low incidence (<0.01%). Surveys were also conducted to assess the potential reservoir hosts of PVY, CMV and AMV among weeds collected from highly infected tobacco fields from 1998 to 2000. Among 3450 samples tested for PVY, plants from 17 species in 10 families were found infected. For CMV, 2891 weed samples were tested and 19 species in 12 families were positive. Assays for AMV infection were made on 961 samples and 12 species in 9 families were identified as hosts of this virus.     

抗旱保水剂对烤烟生长及品质的影响研究

通过大田试验研究了保水剂对烤烟生长及对其品质的影响,结果表明,保水剂的施用在烟草生长前期抑制了烟草的生长,但随生长期的延长,抑制作用有所缓解;低剂量保水剂(15 kg/hm2)的施用提高了烟叶中还原糖、钾的含量,并能显著地降低淀粉、烟碱和氯离子的含量,有利于烟叶品质的改善.保水剂的施用量为15 kg/hm2和30 kg/hm2时能明显提高烟叶的经济性状,增加烤烟生产的经济效益.     

Infection of cowpea mesophyll protoplasts by tobacco mosaic virus and tobacco necrosis virus

Samenvatting Protoplasten werden geïsoleerd uit cowpeabladeren en konden worden geïnfecteerd met tabaksmozaïekvirus en tabaksnecrosevirus serotype A. De virusvermeerdering in de protoplasten werd tot twee dagen na de inoculatie onderzocht.     

电化学酶联免疫分析检测烟草花叶病毒和烟草环斑病毒

以邻苯二胺 (OPD)底物为例 ,用抗原直接包被法 (DAC -ELISA)同线性扫描极谱法 (LSV)相结合 ,检测烟草花叶病毒 (TMV)的提纯液 ,检出限可达 0 2 5ng/ml,TMV粗提液的最高稀释比为 1 :1 0 2 4 0 0 ;检测烟草环斑病毒 (TRSV)提纯液 ,检出限为 1 0ng/ml,粗提液的最高稀释比为 1 :1 0 0 0 0 ,该方法的灵敏度比DAC -ELISA光度法提高了 5倍以上     

Nigerian tobacco latent virus: a new Tobamovirus from tobacco in Nigeria

Field-grown tobacco plants in Nigeria showing chlorotic mottle and marginal veinbanding on the leaves apparently contained several viruses. One of them proved to be a new Tobamovirus for which we suggest the name Nigerian tobacco latent virus (NTLV), because it did not produce systemic symptoms on various cultivars of Nicotiana tabacum. Sequence analyses of the coat and movement protein genes and their translation products, as well as serological studies, revealed that NTLV is only distantly related to known Tobamoviruses from which it also differs in host range and symptomatology. Its closest relationship was found to Tobacco mild green mosaic virus (TMGMV). The percentages of amino acid sequence identity amounted to 73% for the coat proteins and to 64% for the movement proteins of the two viruses. The total sequence of 1415 nucleotides analysed share 63% identity with the corresponding region of TMGMV. In the immunoelectron microscopical decoration test using antisera at a dilution of 1 : 50, reactions of NTLV were observed only with its own antiserum and one out of two antisera to TMGMV. An antiserum to NTLV diluted 1 : 2 failed to react with TMGMV. NTLV induces the formation of characteristic inclusions in infected cells.     

Resistance of Capsicum species to tobacco,tomato and pepper strains of tobacco mosaic virus

A number ofCapsicum accessions including nine species were tested for resistance to TMV based on hypersensitivity. The tobacco strain MA and the tomato strain SPS, which were both isolated from tomato, and two pathogenically distinct pepper strains P 11 and P 8, were used. Of the 73Capsicum accessions tested 58 were resistant to MA and SPS, 31 were resistant to P 11 and five were resistant to P 8.Samenvatting Om verschillen in pathogeniteit tussen twee in Nederland voorkomende paprikastammen van het TMV nader vast te stellen, werd een aantalCapsicum-herkomsten, waaronder negen soorten, op resistentie getoetst. Hierbij werden de representatieve paprika-isolaten P 11 en P 8 vergeleken met de uit tomaat afkomstige isolaten MA en SPS als vertegenwoordigers van respectievelijk de tabaks- en tomatestam van het TMV. Bij het beoordelen van de symptomen duidden lokale, necrotische vlekken en afvallen van geïnoculeerde bladeren op resistentie, systemische necrosen of mozaïeksymptomen op vatbaarheid. In deze symptomen kwamen tussen de gebruikte stammen verschillen in virulentie tot uitdrukking. Er werden echter vooral verschillen in agressiviteit waargenomen met betrekking tot zowel afzonderlijke, voor resistentie uitsplitsende,Capsicum-herkomsten als het totale aantal getoetste herkomsten. Van de ruim 73 herkomsten waren er 58 resistent tegen MA en SPS, 31 daarvan tegen P 11, maar slechts vijf daarvan tegen P 8. Deze resistentie tegen P 8 werd gevonden inC. chinense.     

Virus-specific expression of systemic acquired resistance in tobacco mosaic virus- and tobacco necrosis virus-infected ‘Samsun NN’ and ‘Samsun’ tobacco

Systemic acquired resistance induced in intact ‘Samsun NN’ tobacco plants by either tobacco mosaic virus (TMV) or tobacco necrosis virus (TNV) was more effective against challenge inoculation with the same than with the other of the two viruses. However, in trimmed ‘Samsun NN’ plants resistance induced by either of these viruses was stronger against TMV than against TNV. In intact ‘Samsun’ tobacco plants TNV induced a systemic resistance against itself identical to the one expressed in ‘Samsun NN’. Moreover, it induced systemic resistance against TMV as based on a decrease in TMV content in challeng-inoculated leaves. These observations indicate that systemic acquired resistance is not limited to combinations in which both inducing and challenging virus give rise to a hypersensitive reaction, and further point to virus-specific factors regulating the extent of resistance expressed.     

激活蛋白PeaT1诱导烟草对TMV的系统抗性

枯斑三生烟草(Samsun-NN)经激活蛋白PeaT1诱导后接种烟草花叶病毒(Tobacco mosaic virus,TMV),对TMV产生了明显的系统获得抗性,枯斑抑制率达54.15%,枯斑大小也受到一定程度的限制。研究结果表明,PeaT1处理烟草植株下位三片叶不同时间后,其上部叶片中PPO、POD和PAL 3种抗病防御酶活性均比对照提高,第4 d酶活性达到最高值。实时荧光定量PCR检测结果显示,经PeaT1诱导4 d后烟草叶片中抗病相关基因PR1a、PR1b、NPR1在转录表达水平上较未诱导对照都有不同程度的上调。由以上结果我们推测PeaT1诱导烟草产生了系统获得抗性,本研究为进一步阐明PeaT1诱导植物抗病的信号传导途径奠定了基础。     

Estimation of dieldrin in cured tobacco

Estimation of dieldrin in cured tobacco using published methods of clean-up followed by electron-capture g.l.c., suffers from serious interferences. Such interference can be eliminated by Storherr sweep codistillation and t.l.c. on alumina. The limit of detection is 0.01 part/million.     

植物源病毒抑制剂VFB对烟草抗烟草花叶病毒的诱导作用研究

为揭示植物源病毒抑制剂VFB的抗病毒机理,本研究以普通烟和烟草花叶病毒(TMV)为材料,测定了VFB进行预防和治疗处理后烟草中与抗病性相关的部分生理生化指标变化。结果表明:VFB可明显抑制病毒侵染后导致的细胞膜通透性增大;SOD、CAT、β-1,3-葡聚糖酶和几丁质酶等细胞防御酶活性增强,且预防处理的效果优于治疗处理;与抗病性呈正相关的脯氨酸和总游离氨基酸的含量有显著的提高。表明VFB可诱导植物产生抗病性,增强烟草对TMV侵染的抵抗能力。     

Interaction between the helicase domain of the tobacco mosaic virus replicase and a tobacco arginine decarboxylase

In a yeast two-hybrid screening test for tobacco proteins that interact with TMV replicase using the helicase (H) domain as bait, a cDNA clone was selected that encodes a polyamine biosynthetic enzyme, arginine decarboxylase (ADC). In yeast cells, the C-terminal internal region of ADC interacted with the H domain. This observation was confirmed in vitro by far-Western blotting. Inhibition of the binding between the H domain and the IRnHEL (I region and N-terminus of helicase domain) region by ADC using a yeast three-hybrid assay suggested possible interference of the heterodimerization of 126K and 183K by ADC.The nucleotide sequence data of pADCF reported in this study is available in the DDBJ/EMBL/GenBank databases under accession number AB110952     

Genetic aspects of polyacrylic-acid-induced resistance to tobacco mosaic virus and tobacco necrosis virus in Nicotiana plants

Among the Nicotiana tabacum cultivars and hybrids tested, polyacrylic acid (PAA) only induced resistance to tobacco mosaic virus (TMV) and tobacco necrosis virus (TNV) in the cultivars Xanthi-nc (NN) and Xanthi (nn) respectively. This varietal response to the PAA treatment could be sexually transmitted. The complete genetic analysis of the inheritance of the PAA response is reported for the first time, demonstrating that the response is a dominant character with a Mendelian segregation which occurs independently of either the N gene responsible for resistance to TMV or the PRb-protein genes. Possible relationships between the N gene, the gene for the PAA response and the PRb genes are discussed.