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1.
宁波口岸从来自俄罗斯的杨树木质包装中截获一种伞滑刃线虫,经形态学和分子生物学研究,鉴定为杨树伞滑刃线虫。该线虫与伪伞滑刃线虫十分近似,主要鉴定特征是:阴门盖明显腹弯,近阴门盖后半部的虫体明显凹陷;雄虫交合刺近远端边缘平直,无明显凹陷,远端盘状突十分显著;雌虫尾亚圆柱形或近圆锥形,尾端多数呈多变的尾尖突状,偶尔几乎钝圆。该线虫人工培养后雌虫尾形多数介于圆柱形和圆锥形之间,这与原始文献的报道有差异。这是我国口岸首次截获该线虫。  相似文献   

2.
从新加坡进境阔叶木质包装中分离到伞滑刃属松材线虫组新种——新加坡伞滑刃线虫。该线虫雌虫和雄虫体长分别为850(690~961)肿和792(553.950)μm,身体较粗壮,口针15~16μm,侧区有4条侧线,雌虫后阴子宫囊较长(平均102μm),尾部圆锥形(c=20),略向腹面弯曲,末端钝圆,或有极短的尾尖突(1~2μm),雄虫交合刺长(41~48μm),喙突显著,远端有盘状突。该线虫与松材线虫组的B.conicaudatus、B.luxuriosae、B.fraudulentus、B.kolymensis、B.baujardi、B.xylophilus、B.mucronatus及B.abruptus形态上近似,但可从较大的交合剌及雌虫尾部形态来区分。另外用ITS-RFLP方法也可将该线虫区分出来。  相似文献   

3.
本文对宁波口岸进境的新加坡阔叶木包装材料中截获的一种伞滑刃属线虫进行了形态学特征鉴定和分子特征分析,确定其为松材线虫组(xylophilus group)的一个新成员。该群体的主要形态鉴别特征是:雄虫交合刺呈弓形,中弧线长约23μm,基顶不显著,近末端背缘显著凹陷;雌虫有阴门盖,尾锥形,末端锐尖。该群体r DNA的ITS-RFLP图谱与所有已知松材线虫组成员的图谱有差异,基于r DNA的18S r RNA、ITS和28S r RNA-D2/D3区构建的系统发育树显示该群体与松材线虫组成员亲缘关系最近。因标本材料限制,暂作为一种未命名新种来记述报道。  相似文献   

4.
宁波口岸从荷兰进境的毛蕊银莲花种苗中发现一种滑刃属线虫活虫,该群体的主要形态特征为:侧线4条;雌虫尾近圆柱形,末端有尾尖突,长1.6~2.2μm,其上有多个微小瘤状突;后阴子宫囊显著,长77.7~121.3 μm.雄虫尾端有1.7~2.5 μm的尾尖突,交合刺为玫瑰刺状,有显著的基顶和喙突,背缘远端腹弯,形成小勾状,中...  相似文献   

5.
厦门口岸于2011年6月从来自希腊的荒料石垫木中截获一种伞滑刃属线虫。经形态学比较、测量,该线虫虫体细长,侧区有4条侧线。雌虫有小阴门盖,尾圆锥形,略腹弯,尾端尖。雄虫交合刺成对,不愈合,显著腹弯,长约13~15μm;基顶前伸,端部圆滑,略背弯;喙突显著,末端钝尖,远端有小而明显的盘状突;雄虫尾部乳突7个。结合ITS-RFLP指纹图谱比对,进一步将该线虫鉴定为瓦里西伞滑刃线虫(Bursaphelenchus vallesianus Braasch,Schonfeld,Polomski,et al,2004)。  相似文献   

6.
进境木质包装中豆伞滑刃线虫的鉴定   总被引:1,自引:0,他引:1  
顾建锋  张慧丽  郑炜 《植物检疫》2007,21(3):145-148
豆伞滑刃线虫由宁波出入境检验检疫局植检室验室于2004年6月首次从台湾的针叶木质包装中截获并报道以来,至今共截获17批次,分别来自韩国(6批次)、中国台湾(4批次),日本(4批次),印度(1批次),马来西亚(1批次)和南非(1批次).该线虫属松材线虫组,与拟松材线虫、松材线虫等十分接近.其主要鉴定特征是:雌虫尾圆锥形略向腹面弯曲,其腹面的边线较平直,而背面的边线明显呈圆弧形;尾尖长约2~4μm,渐细,有时呈丝状,位于腹面;雄虫交合刺较大(约36~40μm),中间部分几乎呈直线.该线虫很容易与拟松材线虫等混淆,当形态学鉴定有困难时,ITS-RFLP方法是十分有效的辅助手段.我国大陆尚未有该线虫发生的报道.  相似文献   

7.
宁波口岸从荷兰番红花种球中分离到大量滑刃属线虫活虫,该荷兰群体的主要形态特征为:雌虫尾呈亚圆柱形,尾端半圆形,尾端腹侧有尾尖突长1.5~3.0μm;后阴子宫囊显著,长89.3~118μmm;侧线3条。基于28S、ITS和18S基因DNA序列构建NJ系统发育进化树显示该荷兰群体与次薄滑刃线虫亲缘关系极近且在同一进化分支中。通过形态特征和DNA序列分析,鉴定该荷兰群体为次薄滑刃线虫(Aphelenchoides subtenuis Cobb,1926)。  相似文献   

8.
拟松材线虫尾部形态多样性研究   总被引:2,自引:0,他引:2  
本文对14个拟松材线虫群体和2个松材线虫群体进行了研究,研究表明拟松材线虫群体尾尖突平均长度为3.28~5.82μm,尾形有6种,主要为亚洲型和欧洲型两种。拟松材线虫和松材线虫的交合伞复杂多样,共有12种类型,两者的交合伞没有明显差别,都由2种或2种以上形态构成。交合伞的多样性和不确定性表明,以此作为一个主要分类特征是不恰当的。  相似文献   

9.
宁波口岸首次截获弗氏伞滑刃线虫   总被引:1,自引:0,他引:1  
宁波口岸于2008年7月从来自荷兰的木质包装中截获一种伞滑刃属线虫.该线虫虫体细长,侧区有4条侧线.雄虫交合刺细弱,基顶略呈方形,有时背弯;喙突显著,末端锐尖;远端有较小盘状突.尾乳突7个.雌虫有小阴门盖,尾圆锥形,尾端钝尖,有时呈尾尖突状.经形态学比较、测量以及ITSRFLP图谱比对,鉴定为弗氏伞滑刃线虫(Bursaphelenchus fuchsi Kruglik & Eroshenko,2004).目前除俄罗斯、德国外,未见该线虫的报道.  相似文献   

10.
2002年11月14日,宁波出入境检验检疫局技术中心动植物科对宁波北仓局送检的木质包装检疫时,检出大量伞滑刃属线虫,雄虫交合刺强壮,弓状,喙突显著,远端膨大;雌虫具阴门盖,尾端宽圆,少数具极短的尾尖突,符合松材线虫各项特征,鉴定为松材线虫Bursaphe Lenchus xylophilus,并用PCR快速检测方法确认.  相似文献   

11.
In 1975 many tumours were observed in plants ofBegonia Schwabenland grown in Aalsmeer. Submersion of the roots ofNicotiana megalosiphon seedlings in a homogenate of tumorous tissue, induced tumours after two weeks. Short periods of submergence yielded results similar to those obtained after longer periods. Tumour homogenates lost their infectivity after ten min at 50°C. Aphids transmitted the infectious agent.Treatment with propylene oxide did not inhibit infectivity completely. Filtration through a 450 nm filter removed the infectious agent.Tobacco tumor virus or a viroid could not be isolated. Cultures ofCorynebacterium fascians, isolated from tumours ofN. megalosiphon were highly infectious and induced tumours in healthyN. megalosiphon andBegonia. Tumorous tissue homogenates ofPelargonium zonale, Dahlia sp.,Gladiolus sp., andLilium sp. also caused tumours inN. megalosiphon, from whichC. fascians was isolated. It was not possible to produce tumours inN. megalosiphon with homogenates from roses with symptoms of bud proliferation.Samenvatting In 1975 werden vele tumoren waargenomen inBegonia Schwabenland op Aalsmeerse bedrijven (Fig. 1). De infectiositeit van tumorweefsel kon goed en snel worden vastgesteld door de wortels van zaailingen vanNicotiana megalosiphon in een homogenaat van tumorweefsel te dompelen. Tumoren ontstonden na twee weken, de eindbeoordeling geschiedde na een maand (Fig. 2). Ook verschillende andereNicotiana spp.,Melilotus officinalis (Fig. 3) enPisum odoratum (Fig. 4) werden aangetast.Bij de infectiositeitstoets gaven zeer korte dompeltijden even goede resultaten als langere (Tabel 1). Infectieus sap verloor zijn infectievermogen na 10 min verhitting bij 50°C. Bladluizen brachten de smetstof over. Propyleenoxide verminderde de infectiositeit wel, doch onderdrukte deze niet totaal. Bij filtratie door een 450 nm filter bleef het infectieuse agens op het filter achter. Het tumor-inducerende agens was ook aanwezig in die delen van planten met tumoren welke gezond leken en het ging voor een gering deel over met zaad (Tabel 2).Uit tumoren konden wij geen tabakstumorvirus of een viroïde isoleren. Culturen vanCorynebacterium fascians, geïsoleerd uit tumoren vanN. megalosiphon bleken zeer infectieus en veroorzaakten tumoren inN. megalosiphon enBegonia. Homogenaten van tumorweefsel vanPelargonium zonale, dahlia (Fig. 5), gladiool (Fig. 6) enLilium Mid Century Hybrid Enchantment (Fig. 7) veroorzaakten ook tumoren opN. megalosiphon, waaruitC. fascians werd geïsoleerd. Met sap van kroeskopzieke rozen konden wijN. megalosiphon niet besmetten.  相似文献   

12.
Plant Viruses Transmitted by Whiteflies   总被引:18,自引:0,他引:18  
One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.  相似文献   

13.
The epidemiology ofSitobion avenae and its natural enemies in winter wheat was studied in 1975, 1976 and 1977. Immigration was important until the end of flowering. The alate immigrants had apterous offspring. These became the driving force in population growth. Their offspring were mostly alatae which usually left the field. A model of the epidemic was developed. Quantitative relations between the aphids and their environment were obtained from literature or established in laboratory trials. The model simulated population development and population composition from the beginning of June till the population peak at the end of June or early in July. Because quantitative data on relations between aphids and their natural enemies and pathogens are scarce, and since the knowledge on wing formation is still limited, the population collapse could not be predicted. In the future, prognosis over a period of three weeks seems possible.Samenvatting De toenemende betekenis van graanbladluizen (vooralSitobion avenae) gepaard gaande met een sterke toename van het gebruik van insecticiden op granen maakte verbetering van de prognose over het schadelijk optreden wenselijk. Door gedetailleerde tellingen in het veld (Fig. 1–7) werden gegevens verkregen over het verloop van de epidemie en het optreden van natuurlijke vijanden in 1975, 1976 en 1977.Een immigratieperiode tot in de bloei kon worden vastgesteld. Daarna lijkt de aantrekkelijkheid van het gewas voor alate luizen te verminderen. De alate immigranten krijgen aptere nakomelingen. Deze vormen de stuwende kracht van de populatiegroei. De nakomelingen van apteren zijn merendeels alaat. Zij verlaten het gewas.Een model van de populatieontwikkeling gedurende de epidemie werd opgesteld. De relatiediagrammen Fig. 9 en 10 laten groei en ontwikkeling vanS. avenae en een predator (Syrphus corollae) zien. Kwantificering van de betrekkingen werd mogelijk door literatuurgegevens en laboratoriumexperimenten.Met het model kon de populatieontwikkeling vanS. avenae vanaf begin juni tot aan de populatiepiek in 1975, 1976 en 1977 vrij goed worden gesimuleerd (Fig. 12). Ook de populatieopbouw kon worden gesimuleerd (Fig. 14). De teruggang van de populatiedichtheid blijkt moeilijker te voorspellen door het ontbreken van gegevens over natuurlijke vijanden.Het lijkt waarschijnlijk dat in de toekomst met het model een prognose over de piek van de bladluispopulatie circa 3 weken tevoren mogelijk zal zijn.  相似文献   

14.
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.  相似文献   

15.
Barley yellow dwarf disease is one of the most important problems confronting cereal production in Iran. Barley yellow dwarf virus-PAV (BYDV-PAV) and Cereal yellow dwarf virus-RPV (CYDV-RPV) are the predominant viruses associated with the disease. One isolate of BYDV-PAV from wheat (PAV-IR) and one isolate of CYDV-RPV from barley (RPV-IR) were selected for molecular characterisations. A genome segment of each isolate was amplified by PCR. The PAV-IR fragment (1264 nt) covered a region containing partial genes for coat protein (CP), read through protein (RTP) and movement protein (MP). PAV-IR showed a high sequence identity to PAV isolates from USA, France and Japan (96–97%). In a phylogenetic analysis it was placed into PAV group I together with PAV isolates from barley and oats. The fragment of RPV-IR (719 nt) contained partial genes for CP, RTP and MP. The sequence information confirmed its identity as CYDV. However, RPV-IR showed 90–91% identity with both RPV and Cereal yellow dwarf virus-RPS (CYDV-RPS). Phylogenetic analyses suggested that it was more closely related to RPS. These data comprise the first attempt to characterise BYD-causing viruses in Iran and southwest Asia. The nucleotide sequence data reported appear in the EMBL, GenBank and DDBJ Nucleotide Sequence Databases under the accession numbers AY450425 and AY450454  相似文献   

16.
During a survey conducted from 1998 to 2002, Fusarium proliferatum was found associated with young and adult palms belonging to the genera Chamaerops, Phoenix, Trachycarpus and Washingtonia showing symptoms of wilt and dieback. The fertility and toxicological profile of 36 strains representing different locations and hosts were studied. All of them except two, which were infertile, belonged to mating population D. Both mating types (MATD-1 and MATD-2) were isolated from the same host species, showing a high potential of genetic recombination in the field. Additionally, eight strains were fertile once crossed as female. Toxin analysis showed differences in the ability of strains to produce fumonisin B1, moniliformin, beauvericin, fusaric acid and fusaproliferin. Only 17 of them produced all the toxins analyzed. Pathogenicity tests were conducted on Phoenix dactylifera and P. canariensis using nine F. proliferatum Spanish strains and two reference strains from Saudi Arabia. Eight months after inoculation all strains caused disease, with palms showing lesions on the bases of leaves and development of wilt symptoms similar to those originally observed in affected plants. This is the first report on the occurrence of F. proliferatum on P. dactylifera in Spain and also the first report of this pathogen on C. humilis, P. canariensis, P. reclinata, T. fortunei, W. filifera and W. robusta.  相似文献   

17.
Isolates of an unidentified Rhizoctonia sp. (UR isolates) were obtained from creeping bentgrass and Kentucky bluegrass with reddish brown sheath and foliar rots. Because the UR isolates anastomosed with isolates of three varieties of Waitea circinata (var. oryzae, var. zeae, and var. circinata), colony morphology, hyphal growth rate at different temperatures, pathogenicity, sequence analysis of the internal transcribed spacers (ITS) region of ribosomal RNA genes (rDNA) were compared. The colony color of mature UR isolates was distinct from isolates of the other three varieties of W. circinata. In pathogenicity tests on creeping bentgrass, the severity of the disease caused by UR isolates was significantly higher than that caused by the three varieties of W. circinata. Sequence similarities of the rDNA-ITS region between UR isolates and between isolates within each variety were high (97–100%), but they were lower among isolates from UR and the varieties of W. circinata (88–94%). In a phylogenetic tree based on the rDNA-ITS sequences, UR isolates formed a cluster separate from each of the clusters formed by the three varieties of W. circinata. These results indicate that the UR isolates clearly differ from the three varieties of W. circinata. We therefore propose that the UR isolates be classified as new Rhizoctonia sp. that are closely related to W. circinata and that the disease on creeping bentgrass should be called Waitea reddish-brown patch disease (Sekikasshoku-hagusare-byo in Japanese).  相似文献   

18.
Corynebacterium fascians, which causes leafy gall, has been shown to be responsible for the unusual symptoms recently found in lilies. The symptoms are described and the different bacterial isolates compared by biochemical, serological and pathogenicity experiments. No evidence could be found for the existence of specialized strains even though considerable variation in virulence could be demonstrated. Although the role of variation in susceptibility of the different lily cultivars should not be underestimated, it would appear that high inoculum levels ofC. fascians in the soil may be largely responsible for these outbreaks.Also included in this study are the results of biochemical, serological and pathogenicity experiments ofC. fascians which has been isolated fromKalanchoe, Euphorbia, Brodiaea, Hebe andVerbascum.Samenvatting Reeds een aantal jaren was in lelies een woekering in stengelbollen bekend, die echter sporadisch voorkwam en economisch van weinig betekenis was. Tijdens de zomer van 1977 echter trad de ziekte op één enkel perceel zo ernstig op dat zeer aanzienlijke oogstderving het gevolg was. Behalve de stengelbol kan ook de hoofdbol misvormd zijn. Bovendien kunnen misvormde stengelbollen lange spruiten vormen, zgn. sabeltandvorming. Soms is het wortelstelsel gereduceerd; in de kas zijn verdikte stengels waargenomen. De ziekte staat nu bekend onder de naam woekerziekte.Door de PD te Wageningen en het LBO te Lisse werd de bacterieCorynebacterium fascians (Tilford) Dows. uit het zieke materiaal geïsoleerd. In gezamenlijk onderzoek werd nagegaan of de bacterie de veroorzaker is van bovengenoemde symptomen en of hier sprake is van een op lelie gespecialiseerde stam.Biochemische en serologische vergelijkingen tussen isolaten vanC. fascians uit lelie,Kalanchoe, Euphorbia, Brodiaeea, Hebe enVerbascum laten zien dat er zeer weinig verschillen bestaan. Alle isolaten reageren op een standaard antiserum met titers variërend tussen 1: 640–1: 5120.Een oriënterende inoculatieproef werd uitgevoerd op het LBO in 1977. Daarna werden op de PD 10 van de 25 isolaten uit lelie en 8 uit andere waardplanten getoetst op lelie, chrysant en lathyrus. Uit de inoculatieproeven blijkt, dat de bacterie de veroorzaker is van de waargenomen symptomen. Tussen de isolaten blijkt een groot verschil in pathogeniteit te bestaan (12–100% aantasting), zonder dat dit aan herkomst gebonden is. Het voorkomen van op lelie of andere waardplanten gespecialiseerde stammen is daarom niet aan te nemen.In hoeverre de hevige aantasting een gevolg is van een opbouw van de bacterie-populatie door een te nauwe vruchtwisseling en mechanische rooimethoden moet worden nagegaan.  相似文献   

19.
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.  相似文献   

20.
Organic amendments and green manure are potential alternatives to the harmful chemical control means currently used against plant-parasitic nematodes. In this work, Chrysanthemum coronarium was applied to the soil as a green manure to control the root-knot nematodes Meloidogyne incognita and M. javanica. Chrysanthemum coronarium significantly reduced nematode infection of tomato roots and improved plant-top fresh weight, both in the greenhouse and in microplots. Other green manures, derived from Anthemis pseudocotula, wild chickpea (Cicer pinnatifidum), Geranium spp. and wheat, were not as effective as C. coronarium. Chrysanthemum coronarium, retained its nematicidal activity even when applied as a dried material. Only mature C. coronarium plants, in their flowering stage, exhibited nematode control activity, but the green plant parts were more effective than the flowers. An aqueous extract of C. coronarium exhibited in vitro, nematostatic activity towards M. incognita and M. javanica second-stage juveniles and inhibited their hatching from eggs and egg-masses; its nematostatic activity was expressed also against other phytonematode species such as Heterodera avenae and Pratylenchus mediterraneus, but did not affect the beneficial entomopathogenic nematode Steinernema feltiae.  相似文献   

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