基于TaqMan MGB探针的花生矮化病毒检测研究

花生矮化病毒(Peanut stunt virus,PSV)是我国进境检疫性有害生物。本研究根据该病毒不同分离株外壳蛋白基因(coat protein,CP)的保守序列,设计了特异性引物与TaqMan MGB荧光探针,建立了PSV的实时荧光RT-PCR检测方法。方法特异性研究表明,针对PSV的2个不同株系PSV-E和PSV-W,均能够得到典型扩增曲线,Ct值分别为20.10和21.22;而对于黄瓜花叶病毒、番茄不孕病毒、马铃薯Y病毒、菜豆荚斑驳病毒以及烟草环斑病毒等其他毒株则没有典型扩增曲线,也无Ct值。灵敏度比较发现,该方法比普通RT-PCR检测方法的灵敏度提高100倍,具有快速、灵敏和高特异性的优点,适合对PSV的检测。     

玉米褪绿斑驳病毒实时荧光RT-PCR检测方法研究

玉米褪绿斑驳病毒(Maize chlorotic mottle virus,MCMV)是我国对外公布的检疫性有害生物。本研究根据该病毒外壳蛋白基因的保守序列,设计得到特异性引物及Taqman荧光探针,建立了MCMV的实时荧光RT-PCR方法,并对其灵敏度与特异性进行了研究。该方法针对2个不同来源的毒株均能得到典型扩增曲线,而没有从小麦线条花叶病毒、玉米粗缩病毒和玉米矮花叶病毒的RNA得到扩增曲线,表明引物与荧光探针具有良好的特异性。针对玉米褪绿斑驳病毒RNA不同稀释度样品,实时荧光RT-PCR检测低限达到10-5稀释度,检测灵敏度要比普通RT-PCR高出100倍。因此,本研究建立的MCMV实时荧光方法具有特异性强、灵敏度高和快速有效的优点。     

番茄褐色皱果病毒TaqMan 荧光定量RT-PCR检测方法的建立及应用

为建立番茄褐色皱果病毒(tomato brown rugose fruit virus, ToBRFV)TaqMan荧光定量RT-PCR方法，本研究针对ToBRFV RNA依赖的RNA聚合酶(RNA-dependent RNA polymerase, RdRP)基因序列设计了4组特异性引物和TaqMan探针，构建了标准曲线，并对该方法的特异性、灵敏度和实际样品的检测效率进行评估。结果显示，该方法特异性强，与番茄花叶病毒、番茄斑驳花叶病毒、烟草花叶病毒、黄瓜绿斑驳花叶病毒、番茄环斑病毒、番茄黑环病毒、辣椒轻斑驳病毒、烟草环斑病毒和凤果花叶病毒等9种病毒均无交叉反应。建立的标准曲线的R²为0.999,扩增效率为102.096%,检测灵敏度为10 fg/μL,与EPPO PM 7/146(1)推荐的CaTa28、CSP1325方法相当，是常规RT-PCR的100倍；采用该方法成功从60份番茄和辣椒叶片、种子样品中检出10份阳性样品。建立的TaqMan荧光定量RT-PCR方法特异性强、灵敏度高，适用于实际样品中ToBRFV的快速精准检测。     

大麦条纹花叶病毒荧光定量PCR检测方法的建立及应用

大麦条纹花叶病毒Barley stripe mosaic virus（BSMV）是我国进境植物检疫性有害生物。为提高大麦条纹花叶病毒检测的灵敏度和特异性,缩短检测周期,根据该病毒不同分离株外壳蛋白（coat protein, CP）基因的保守序列设计特异性的引物和探针,建立了BSMV的实时荧光RT-PCR检测方法。结果表明,本检测方法特异性强,对南方菜豆花叶病毒Southern bean mosaic virus（SBMV）、小麦线条花叶病毒Wheat streak mosaic virus（WSMV）、玉米褪绿斑驳病毒Maize chlorotic mottle virus（MCMV）、烟草环斑病毒Tobacco ringspot virus（TRSV）、菜豆荚斑驳病毒Bean pod mottle virus（BPMV）和番茄环斑病毒Tomato ringspot virus（ToRSV）6种病毒均无交叉扩增;且检测方法灵敏度高,对RNA模板的最低检测限达到5×10-4 ng/μL,与双抗体夹心酶联免疫吸附法（DAS-ELISA）和普通RT-PCR相比,本方法的灵敏度分别提高了10倍和100倍。此外,我们利用该方法对12批进口大麦进行检测,发现6批大麦中检出大麦条纹花叶病毒,占比约50%。总之,本研究建立的荧光定量PCR方法具有灵敏度高、特异性强等优点,适合于BSMV的快速检测。     

甘蔗黄叶病毒外壳蛋白基因克隆及其实时荧光RT-PCR检测

 甘蔗黄叶病毒（Sugarcane yellow leaf virus, SCYLV）引起的甘蔗黄叶病是一种新的全球性病毒病害。本文以YLSCPF1和YLSCPR591为引物,采用RT-PCR方法克隆了甘蔗黄叶病毒福建分离物（CHN-FJ1）外壳蛋白（CP）基因,编码196个氨基酸。分析不同地理来源的SCYLV病毒分离物cp基因核苷酸及其推导编码的氨基酸序列,同源性达95%以上。根据cp基因的保守序列,设计1对特异性引物和TaqMan探针,建立了SCYLV的TaqMan实时荧光RT-PCR方法。结果表明,检测下限为初始质粒模板DNA 1 000拷贝/μL（约3.61 fg/μL）,比常规PCR方法的灵敏度提高100倍。检测甘蔗花叶病毒、宿根矮化病菌和黑穗病菌,没有典型的扩增曲线和无Ct值。应用实时荧光RT-PCR、常规RT-PCR和组织印迹免疫杂交（TBIA）对田间甘蔗叶片样品进行检测,阳性检出率分别为100%、61.5%和69.2%,表明该方法比常规RT-PCR和TBIA具有更高的灵敏度,适合于对SCYLV的检测。     

实时荧光RT-PCR方法检测黄瓜绿斑驳花叶病毒

根据黄瓜绿斑驳花叶病毒不同分离物外壳蛋白基因(CP)的保守序列,设计合成引物和TaqMan荧光探针,建立了黄瓜绿斑驳花叶病毒的实时荧光RT-PCR(Real time RT-PCR)检测方法.该方法利用TaqMan探针水解产生的荧光信号实时监测目标基因的扩增,实现PCR扩增与检测同步进行.结果表明,实时荧光RT-PCR方法检测灵敏度比普通RT-PCR高约10倍,并且具有快速、简便、准确的优点,适合于CGMMV的快速、高效检测.     

大麦条纹花叶病毒实时荧光RT-PCR检测方法的建立及应用

大麦条纹花叶病毒为禾本科作物上一种重要的病原,可造成严重的经济损失。该病毒的主要传播方式为种传,因此对种子进行检疫监管是控制病害传播的一种有效途径。本文依据病毒保守序列RNA2beta C蛋白设计引物,研发了一种实时荧光RT-PCR检测方法。经特异性与灵敏度评价,仅对大麦条纹花叶病毒有效,无法对小麦线条花叶病毒、甘蔗花叶病毒及玉米褪绿斑驳病毒的阳性样品进行鉴定;且扩增灵敏度与普通RT-PCR相当,处于0.02 ng/μL水平。该方法相较于已有的检测方法,操作更简便快速,不易污染,灵敏度高,特异性优。此外,本研究结合实时荧光RT-PCR与普通RT-PCR两种检测方法,对未知谷物粉进行大麦条纹花叶病毒的检测鉴定,证实了新方法的可行性。     

啤酒花矮化类病毒实时荧光定量RT-PCR检测方法的建立与应用

为建立一种快速、灵敏、特异的定量检测啤酒花矮化类病毒(Hop stunt viroid,HSVd)的实时荧光定量RT-PCR (RT-qPCR)方法,设计了2对引物及特异探针,体外转录制备了RNA标准品,绘制标准曲线,并对该方法的特异性、灵敏度和重复性进行评估.建立的定量标准曲线Ct值与模板拷贝数对数之间呈良好的线性关系,相关系数R2为0.9988,扩增效率为95％;该方法的特异性好,与啤酒花潜隐类病毒(HLVd)、葡萄黄斑类病毒1(GYSVd-1)、葡萄黄斑类病毒2(GYSVd-2)和桃潜隐花叶类病毒(PLMVd)均无交叉反应;灵敏度为1.0×102拷贝/μL,比普通RT-PCR高10倍;试验内及试验间重复性试验的变异系数均小于3％.研究表明该方法适用于实际样品中HSVd的快速定量检测.     

环介导等温扩增技术检测小苍兰花叶病毒

小苍兰花叶病毒Freesia mosaic virus(FreMV)是侵染兰花的主要病毒,严重影响其观赏价值。本研究根据FreMV的外壳蛋白基因序列设计了一组特异性引物,经过一系列条件优化,建立了该病毒的RT-LAMP检测方法。结果显示设计引物能特异扩增FreMV,与其他4种病毒(菜豆黄花叶病毒Bean yellow mosaic virus、黄瓜花叶病毒Cucumber mosaic virus、建兰花叶病毒Cymbidium mosaic virus和齿兰环斑病毒Odontoglossum ringspot virus)不发生反应;该方法灵敏度为RT-PCR的10倍。田间检测20份样品中,RT-LAMP和RT-PCR检测结果一致,检出率为60%。在产物中加入荧光染料SYBR GreenⅠ直接用肉眼观察就可判断样品是否感染FreMV,可省去电泳分析的时间。该方法具有特异性强、灵敏度高、操作简单、快速等特点。     

Dermestid beetles in ‘evolution Canyon’, lower Nahal Oren, Mt. Carmel, including new records for Israel

Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr _s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr _s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.     

Epidemiology of Toxigenic Fungi and their Associated Mycotoxins for Some Mediterranean Crops

Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.     

Broad bean mottle virus in Morocco; curculionid vectors,and natural occurrence in food legumes other than faba bean (Vicia faba)

Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.     

Characterization of potato potyvirus Y (PVY) isolates from seed potato batches. Situation of the NTN, Wilga and Z isolates

A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVY^N strain and six to the PVY^O strain. No PVY^C was found. Two other isolates reacted serologically like PVY^O, but were unable to elicit a hypersensitive response from the Ny_tbr gene and probably represent the PVY^Z group. At the molecular level, these two isolates showed a combination of both PVY^O and PVY^N and could be recombinants of these strains. Another isolate reacted serologically like PVY^O, but induced vein necrosis in tobacco, like PVY^N-Wilga. Some PVY^N isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVY^NTN group. The PVY^NTN, PVY^N-Wilga and PVY^Z groups probably represent pathotypes within strains PVY^N and PVY^O, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.     

The autumn leafroller: Phenology,damage and parasitoids in a Dutch apple orchard

The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.     

Characterization of Sclerotinia minor populations in Texas peanut fields

In the summer of 2004 an epidemic of sclerotinia blight of peanut, a disease caused by Sclerotinia minor, occurred in Texas in fields where the disease was never previously detected. The disease was observed on many plants within one of the fields (>3000 disease foci), although most foci were <1 m. It is hypothesized that these observations were inconsistent with the recent introduction of a monocyclic pathogen, even if disease developed under conducive environmental conditions. The pattern of disease is most suggestive of the presence of foliar (ascospore) infections, although air temperature was above the known limits for apothecia development if the pathogen had arrived in the field in 2004 peanut seed. To further examine this epidemic, 232 isolates were collected, across a variety of spatial scales spanning this field and other Texas peanut fields, and evaluated for aggressiveness, fungicide sensitivity and genotypic diversity. There was wide variation among isolates for the phenotypic characteristics measured, but there was no evidence that a genotypically unique, highly aggressive, and fungicide resistant isolate had been introduced or evolved. The predominant genotype, TX1, which contained 154 isolates, was found in every county and field population.     

Eyespot of Cereals Revisited: ITS phylogeny Reveals New Species Relationships

Four species so far classified in Pseudocercosporella or Ramulispora (hyphomycetes) are associated with eyespot disease symptoms of cereals. Two of these have been linked to teleomorphs that were described in Tapesia. Sequence data derived from the Internal Transcribed Spacer region (ITS1, 5.8S and ITS2) of the rDNA operon showed, however, that the eyespot fungi associated with Tapesia are not congeneric with Ramulispora sorghi, the type of Ramulispora. The genus name Tapesia is now rejected in favour of the conserved name Mollisia, which appears to comprise heterogeneous fungi. Tapesia yallundae is not closely related to the type of Mollisia, M. cinerea, but clusters separately, being more closely allied to species with Cadophora anamorphs. A new holomorph genus, Oculimacula, is therefore proposed for teleomorphs of the eyespot fungi, while the anamorphs are accommodated in Helgardia gen. nov.     

Transgene herbizidresistente Kulturen

Zusammenfassung Herbizidresistente Kulturpflanzen nehmen unter den derzeit weltweit angebauten gentechnisch veränderten Ackerbaukulturen Sojabohne, Baumwolle, Raps und Mais den weit überwiegenden Anteil ein. Als Ursachen für die rasche Zunahme der Anbauflächen herbizidresistenter Sorten sind unter anderem die Unzulänglichkeiten der für diese Kulturen bestehenden Herbizidlösungen sowie die Zunahme der pfluglosen Bestellverfahren zu sehen. Im Gegenzug hat die Minimalbodenbearbeitung aufgrund der Einführung der Herbizidresistenztechnologie, insbesondere in Sojabohne, ein ausgeprägtes Flächenwachstum erfahren.Als Entscheidungskriterien für die Wahl des Unkrautbekämpfungssystems unter Einbezug des Anbaus herbizidresistenter oder konventioneller Sorten lassen sich aus den Erfahrungen der vergangenen 8 Jahre anführen: Sortenleistung, erhöhte Kulturverträglichkeit und zeitliche Anwendungsflexibilität, Wirkungssicherheit einer Nachauflaufbehandlung in Trockenregionen, Wirkungsbreite, Wirkungsdauer und Bekämpfung resistenter Unkrautbiotypen. Aufgrund fehlender Zulassungen und Kennzeichnungsvorschriften in wichtigen Exportmärkten sind für den Anbau transgener Sorten in Übersee auch Vermarktungseinschränkungen sowie für den Anbau in Europa Haftungs- und Koexistenzregeln wichtige einzelbetriebliche Entscheidungsparameter.Fortschritte erfährt die Herbizidresistenztechnologie kurz- und mittelfristig in der Weiterentwicklung bereits praktizierter Spritzfolgen und Tankmischungen zu Fertigformulierungen der Komplementärherbizide mit residualen Partnern. Zur Bekämpfung und Vorbeugung der Ausbreitung neuer herbizidresistenter Biotypen werden die Komplementärherbizide mit Partnern anderer Wirkungsmechanismen kombiniert. Weitere Entwicklungen sind die Kombination verschiedener transgener Merkmale mit der Herbizidresistenz sowie die Ausweitung von den derzeit dominierenden Kulturen auf weltweit weniger bedeutsame Kulturen, in denen die Entwicklung neuer konventioneller Herbizidwirkstoffe bisher wenig erfolgreich war oder im Verhältnis zum Aufwand nur bedingt attraktiv ist. Für die langfristige Entwicklung könnte die Plastidentransformation zur Verhinderung einer unerwünschten Ausbreitung transgener Merkmale Bedeutung erlangen.     

Pathogenic fungi involved in root rot of peas in the Netherlands and their physiological specialization

Research on root rot pathogens of peas in the Netherlands has confirmed the prevalence ofFusarium solani, F. oxysporum, Pythium spp.,Mycosphaerella pinodes andPhoma medicaginis var.pinodella. Aphanomyces euteiches andThielaviopsis basicola were identified for the first time as pea pathogens in the Netherlands. Other pathogens such asRhizoctonia solani andCylindrocarpon destructans were also found on diseased parts of roots. F. solani existed in different degrees of pathogenicity, and was sometimes highly specific to pea, dwarf bean of field bean, depending on the cropping history of the field.A. euteiches was specific to peas, whereasT. basicola showed some degree of physiological specialization.     

Surveys of cereal diseases and pests in the Netherlands. 3. Monographella nivalis and Fusarium spp. in winter wheat fields and seed lots

Data from surveys of winter wheat fields in the period 1974–1986 and of seed lots in the period 1962–1986 and identifications of diseases on plant samples were compiled to describe the occurrence of snow mould (Monographella nivalis) andFusarium spp. On average,M. nivalis dominated overFusarium spp. The complex ofFusarium spp. constituted mainly ofF. culmorum, followed byF. avenaceum andF. graminearum. M. nivalis was dominant in May on stem-bases and in July on leaves and leaf sheaths. On seedsM. nivalis predominated only in years with low temperatures in July and August.Average brown footrot infection in the field was 4% tillers in May and 5% culms in July. Brown footrot intensity in July was high in cropping seasons with high precipitation in October and with low temperatures in October, November and December. In July during the early eighties, an average of 8% of leaves and 6% of flag leaf sheaths were infected byM. nivalis. Average ear blight incidence was 1.2% glumes infected. Seed contamination by these pathogens averaged 16% in the years 1962–1986. The contamination was high in years with high precipitation in June, July and August. Aspects of cv. resistance and yield loss are illustrated.