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1.
北京口岸从英国邮寄进境的大岩桐(Sinningia speciosa Benth)宿根植物根际介质中分离到1种孢囊线虫属的2龄幼虫,通过形态鉴定和分子特征分析,鉴定其为三叶草孢囊线虫(Heterodera trifolii Goffart,1932)。该英国群体的2龄幼虫体长439~539μm;唇区有3或4个唇环;口针粗壮,长26.3~29.7μm,基部球圆形或前端略凹陷;侧线4条;尾长圆锥形,末端细圆,透明尾长27.7~39.5μm,约占尾长的60%。基于核糖体DNA的28S区和ITS区序列构建的系统发育树证实该鉴定结果。  相似文献   

2.
上海口岸从旅客携带进境的树苗中分离到1种孢囊线虫属的2龄幼虫,通过形态特征和分子特征分析,鉴定为无花果孢囊线虫(Heterodera fici Kirjanova,1954)。该2龄幼虫的主要形态特征为:体长409.9~454.4μm;唇环3个;口针发达,长22.6~24.0μm,基部球圆形略向前倾斜;侧线4条;尾长圆锥形,末端细圆,尾部透明区长24.7~30.5μm,约占尾长的1/2。序列分析显示其ITS区序列与GenBank中无花果孢囊线虫的序列相似性为99.48%~99.90%,序列差异为1~5 bp。系统发育分析显示该线虫与无花果孢囊线虫处于一个聚类组内。这是我国口岸首次报道截获无花果孢囊线虫。  相似文献   

3.
在对广东省主要珍贵树种上的线虫进行调查时从格木Erythrophleum fordii上分离到一种隐皮孢囊线虫,经形态特征观察和测量数据分析,将其鉴定为卡勒萨隐皮孢囊线虫Cryphodera kalesari。其诊断特征为:雌虫椭圆形至近球形,头部具有1个唇盘和2~3个唇环,口针长33.6~37.8μm,阴门唇突出,阴门与肛门之间区域凹陷,肛阴距为42~72μm;2龄幼虫头部具1个明显的唇盘和3个唇后环纹,口针长24.8~29.5μm,口针基部球前缘凹陷,侧区3条侧线,尾长圆锥形,长38~53.5μm,尾末端细圆,透明尾长17.1~25.1μm,侧尾腺孔位于肛门后2~5环;雄虫未发现。本研究首次获得了卡勒萨隐皮孢囊线虫的rDNA(LSU D2D3和ITS)序列,为此线虫的鉴定提供了可靠的分子数据。本研究还分析了卡勒萨隐皮孢囊线虫与本属其他种类的系统进化关系。卡勒萨隐皮孢囊线虫为中国的地理新记录种。格木为隐皮孢囊线虫的新寄主。  相似文献   

4.
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   

5.
日本鸡爪槭中苹果根结线虫的鉴定   总被引:1,自引:0,他引:1  
宁波口岸连续从来自日本的鸡爪槭根和根围介质中截获一种根结线虫,经形态学和分子生物学方法鉴定为苹果根结线虫。其主要鉴定特征是:雌虫会阴花纹卵圆形,线纹平滑细密,背弓和腹弓均低平,侧尾腺口大,侧尾腺间距大于阴门裂宽;雄虫背食道腺开口到口针基部球的距离较大,平均8μm;2龄幼虫体长和尾长均较短,分别为362~466μm和29.2~39.3μm,c=11.6~15.3。所截获的苹果根结线虫18S rDNA序列与已在GenBank登录的2个苹果根结线虫株系(登录号为EU669948和EU669949)最接近,相似度达99.4%和99.6%。这是我国首次报道截获该种线虫。  相似文献   

6.
宁波口岸在进境木质包装检疫中经常截获食菌伞滑刃线虫和阿苏里伞滑刃线虫,这2种线虫都属于fungivorus组,形态上十分近似。主要区别在于:前者唇区缢缩十分明显,而后者缢缩不明显;前者排泄孔与半月体平均距离较远(约11μm),而后者较近(约5μm);前者雄虫热杀死后尾部强烈向腹面弯曲(超过180°),后者尾部略腹弯(约90°);前者基顶与喙突相距约9.8μm,喙突高约2.7~3.5μm,后者则分别为8.4μm和1.5~2.8μm;前者雌虫尾多数腹弯十分明显,尾较短(长约50μm),后者尾一般略腹弯(长约68μm)。此外,ITS区的PCR-RFLP方法可区分上述2种线虫。  相似文献   

7.
为明确云南省紫茎泽兰根结线虫病的病原种类,于2019年2月在云南省澜沧县林下三七种植区采集根部带有明显根结的紫茎泽兰根系进行根结线虫分离,通过观察所分离根结线虫的2龄幼虫、雌成虫、会阴花纹特征对其进行形态学鉴定,并利用序列比对、系统发育树分析、序列特异性扩增区段(sequence characterized amplified region,SCAR)对其进行分子生物学鉴定。结果表明,该病原线虫雌成虫会阴花纹呈圆形至卵圆形,背弓中等高或低平,侧区一侧或两侧延伸形成翼状,尾区有刻点,2龄幼虫、雌成虫形态特征及形态测量指标与北方根结线虫Meloidogyne hapla相似;该病原线虫rDNA的ITS序列和mtDNA的COI序列与NCBI数据库中已登录的北方根结线虫相应序列相似度较高,分别达99.35%和98.05%以上;该病原线虫rDNA的ITS序列、mtDNA的COI序列分别以99%、100%的支持率与北方根结线虫聚为同一分支;利用SCAR特异性引物,该病原线虫均能扩增出大小约1 500 bp的基因特异性条带。综合形态学和分子生物学鉴定结果将云南省紫茎泽兰根结线虫病病原种类鉴定为北方根结线虫。  相似文献   

8.
甘肃河西地区番茄根结线虫病病原鉴定   总被引:7,自引:1,他引:6  
利用形态特征对甘肃省河西地区番茄根结线虫病病原线虫进行鉴定,其重要的形态特征如下:雌虫体长L=599.0(510.0~690.0)μm,体宽W=439.0(409.0~473.0)μm,口针长ST=15.4(15.0~16.0)μm,背食道腺开口到口针基部球的距离DGO=3.6(2.0~4.3)μm。雌虫梨形,排泄孔位于口针基球处,会阴花纹背弓明显高,线纹由平滑到波浪状,有些线纹向侧面分叉,但无明显的侧线;2龄幼虫L=376.0(360.0~393.0)μm,W=14.8(14.2~15.2)μm,ST=11.7(11.2~12.5)μm,DGO=3.6(2.1~4.0)μm,头部前端平,口针基部球明显,半月体邻近分泌和排泄孔,尾透明且纤细,尾尖尖圆;雄虫L=1 411.0(532.0~1 720.0)μm,W=32.0(28.0~38.0)μm,ST=24.5(23.0~26.0)μm,DGO=3.2(2.0~4.1)μm,头区不缢缩,有不完全的头环,没有侧唇,口针基球圆形至扁圆形。综合以上雌虫、2龄幼虫和雄虫的形态特征,确定了该地区的番茄根结线虫病病原线虫为南方根结线虫(Meloidogyne incognita)。  相似文献   

9.
青岛口岸截获的马铃薯白线虫   总被引:1,自引:0,他引:1  
从来自俄罗斯籍轮船携带的带土马铃薯样本中分离线虫,通过胞囊的阴门区和2龄幼虫的形态特征和测量数据,将截获线虫鉴定为马铃薯白线虫(Globodera pallida Behren,1975)。分离到的线虫胞囊内部为奶油色,雌虫阴门和肛门间角质脊数目为10~12,Granek’s ratio为1.95±0.8;2龄幼虫口针长度为23±1.2μm,口针基球剖面的前表面尖,口针锥部占整个口针长度的52.5%;头区深度骨化,六角放射状,口盘及唇部轮廓为矩形,轻微缢缩,有4~6个环纹。马铃薯白线虫是中国一类进口植物检疫对象,该线虫为青岛口岸首次截获。  相似文献   

10.
Vovlas  N 黎少梅 《植物检疫》1989,3(4):269-270
1985年在利比里亚采集旱稻土壤和根样检查植物寄生线虫时,发现旱稻严重感染胞囊线虫。经检查幼虫和胞囊(从水稻根分离)的形态确定:是甘蔗胞囊线虫Heterodera sancchari Luc Merny .在利比里亚出现甘蔗胞囊线虫,说明多了一个  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.  相似文献   

14.
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   

15.
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   

16.
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 PVYN strain and six to the PVYO strain. No PVYC was found. Two other isolates reacted serologically like PVYO, but were unable to elicit a hypersensitive response from the Nytbr gene and probably represent the PVYZ group. At the molecular level, these two isolates showed a combination of both PVYO and PVYN and could be recombinants of these strains. Another isolate reacted serologically like PVYO, but induced vein necrosis in tobacco, like PVYN-Wilga. Some PVYN isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVYNTN group. The PVYNTN, PVYN-Wilga and PVYZ groups probably represent pathotypes within strains PVYN and PVYO, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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   

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