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1.
This is the first report of Monochamus sutor as vector of B. mucronatus kolymensis, the European type of B. mucronatus (synonymous with B. kolymensis) in Spain. In 2013, a female of Monochamus sutor was caught in a Pinus sylvestris forest. Nematode species identification was based on morphological characteristics and on molecular and phylogenetic analysis of dauer juveniles and adults.  相似文献   

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As a result of the detection of the pinewood nematode Bursaphelenchus xylophilus in Portugal, and its subsequent spread to Spain, intense surveys were conducted to screen for the presence of Bursaphelenchus species in Romania. Herein, we report recent surveys of insects potentially vectoring Bursaphelenchus species collected using trap trees or pheromone‐baited traps placed in the forest. Trap felled spruce trees (Picea abies) and pheromone‐baited traps were installed in six different counties in Romania (Bra?ov, Sibiu, Suceava, Hunedoara, Timi? and Dâmbovi?a). Ten different species of insects distributed among Curculionidae and Cerambycidae were obtained. Nematodes were extracted from insects and observed to validate the presence of Bursaphelenchus specimens. One female identified as Monochamus sutor was the only specimen carrying nematodes in the genus Bursaphelenchus. Nematodes were identified as B. mucronatus based on morphological and molecular features. This is the first detection and report of natural spread of B. mucronatus in Romania. The absence of B. xylophilus was confirmed in the areas of Romania surveyed in this work.  相似文献   

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This is the first report and characterization of Bursaphelenchus pinophilus in Portugal. This species was isolated from a young dying Pinus pinaster tree located in Valverde, in the Alentejo region. Nematodes were identified using several morphological diagnostic characters for this species (male spicule structure, number of lateral incisures, number and distribution of the male papillae, presence of female vulval flap and female tail shape) and confirmed using RFLP analysis of the internal transcribed spacer (ITS) regions of ribosomal DNA.  相似文献   

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In Greece extensive pine wilting is associated with the presence of nematodes of the genus Bursaphelenchus. In order to check the pathogenicity of Bursaphelenchus sexdentati, Bursaphelenchus leoni and Bursaphelenchus hellenicus, inoculation tests were carried out on 3‐year‐old seedlings of Pinus brutia, Pinus halepensis, Pinus nigra, Pinus pinaster and Pinus sylvestris. For inoculations, 6000 nematodes in 0.5 ml of water were used per seedling. Bursaphelenchus sexdentati proved to be highly virulent causing mortality of up to 100%, followed by B. leoni whereas B. hellenicus was nonpathogenic.  相似文献   

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宁波出入境检验检疫局植检实验室于2007年12月从来自德国的木质包装中截获一种伞滑刃属线虫。经形态学比较、测量以及ITS—RFLP图谱比对,鉴定为十二齿小蠹伞滑刃线虫(Bursaphelenchus sexdentati)。目前国内尚无该线虫的报道。  相似文献   

8.
A survey of the xylophagous insects in the conifer forests, mainly Pinus pinaster woodlands, in Spain was carried out in order to study the phoretic vectors of nematodes of the genus Bursaphelenchus. Fifteen environmental sites were characterized on the bases of altitude, rainfall, temperature and conifer species. Specimens of Orthotomicus erosus (n = 3476) were captured of which 59% carried nematodes under their elytrous, most of them were aphelenchid fungal‐feeding nematodes, but B. fungivorus was found on the beetles from Las Cumbres, Villa Blanca, (Huelva), southern Spain, which represent the first record of O. erosus as vector of a Bursaphelenchus sp. The nematode is characterized by morphometric and biomolecular techniques and distribution and ecology of the insect is discussed.  相似文献   

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Masson pine stands infected by Pine wilt disease(PWD) in the Three Gorges Reservoir Region of central China were surveyed to quantify the immediate responses and subsequent trajectories of biomass,carbon(C),and nitrogen(N) in stand-level major ecosystem compartments.The biomasses of above-and belowground tree components,as well as of the understory,forest floor,and mineral soil(0–40 cm),were determined within each stand.C and N storage were also estimated for each ecosystem compartment.Overstory biomass decreased steadily with the extent of PWD infection.Understory biomass ranged from1.97 to 4.16 Mg ha~(-1),and the observed value for forest floor biomass was 12.89–22.59 Mg ha~(-1).The highest mean C and N concentrations were found in the stem bark and needles of Masson pine,respectively,while the lowest were found in the semi-to fully decomposed layer of the forest floor and stem wood of Masson pine,respectively.The C and N storage of aboveground trees,tree roots,and the aboveground ecosystem decreased with the extent ofPWD infection.However,the C and N contents of the understory,forest floor,and total mineral soil initially declined after PWD infection before recovering over the following several years.Those result concluded that the biomass,C,and N storage of different forest ecosystem compartments have experienced certain variations following the PWD epidemic.This is vital to understand the shifts in stand-level C and N allocation in PWD-damaged forest stands,as well as for predicting the responses of regional and global C and N cycling.  相似文献   

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A national research program was initiated in 1988 in Sweden to provide more information on the distribution and bionomics ofBursaphelenchus species. As a result of the intimate association known to occur between the pinewood nematodeB. xylophilus (Steiner andBuhrer) Nickle and its insect vectors a survey was directed to Scots pine wood (Pinus sylvestris L.) in whichMonochamus species were breeding. A total of 59M. sutor L. and twoM. galloprovincialis Ol. emerged from the collected material. Fourteen specimens of theM. sutor and bothM. galloprovincialis specimens containedBursaphelenchus nematodes which resembled the speciesB. mucronatus Mamiya andEnda. To our knowledge this is the first record of theB. mucronatus-type nematodes inM. galloprovincialis and the first finding of such nematodes inM. sutor in Europe.  相似文献   

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A new phoretic association between Bursaphelenchus minutus and the bark beetle Orthotomicus erosus collected on Pinus pinea is described for the first time. Nematode identification was based on morphological observation and biometric measurements of males and females. Moreover, B. minutus was characterized by ITS sequences and RFLP profile.  相似文献   

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The pine nematode Bursaphelenchus mucronatus has been associated with pine wilt in China. This work was intended to investigate the role of the pathogenicity‐related β‐1,4‐endoglucanase gene of B. mucronatus in the infection of pines. In this study, the full‐length cDNA of the Bm‐eng‐1 gene was cloned and characterized from a B. mucronatus isolate. Phylogenetic analysis suggested that the Bm‐eng‐1 gene of B. mucronatus may be acquired from fungi through horizontal gene transfer. The function of the gene was demonstrated using RNA interference. RNA interference indicated that Bm‐eng‐1 was involved in the dispersal, reproductive ability and pathogenicity of B. mucronatus. In situ hybridization showed that Bm‐eng‐1 was specifically expressed in the oesophageal gland of B. mucronatus. Furthermore, to investigate the relation between β‐1,4‐endoglucanase activities and virulence of different isolates, the β‐1,4‐endoglucanase activities and the expression levels of Bm‐eng‐1 were detected in six B. mucronatus isolates with different virulence. β‐1,4‐Endoglucanase activity was generally higher in pathogenic isolates than in non‐pathogenic isolates, and the Bm‐eng‐1 expression levels in different isolates were positively correlated with the β‐1,4‐endoglucanase activity. These findings suggested that β‐1,4‐endoglucanase plays important roles in the pathogenic process of B. mucronatus, and the differential expression of the gene may underlie the different activity levels of β‐1,4‐endoglucanase, subsequently influencing variations in virulence of B. mucronatus isolates.  相似文献   

13.
As a consequence of the recent introduction of the pine wood nematode Bursaphelenchus xylophilus in Portugal, nematodes of the genus Bursaphelenchus were looked for in various French pine forests, in trees attacked by Monochamus galloprovincialis, the vector insect of B. xylophilus, and in the insects themselves. Trap trees were felled in 12 localities distributed all over the country. Nematodes were extracted from transversal stem discs; insects emerging from the trap trees were studied. B. hellenicus, B. leoni, B. mucronatus and B. sexdentati were isolated, but not B. xylophilus. The presence of B. mucronatus and the absence of B. xylophilus were confirmed by molecular markers. B. mucronatus was isolated from several regions with an average prevalence of 19%. The infestation of M. galloprovincialis by B. mucronatus reached 26.7%. The wide distribution of B. mucronatus in France could have an effect on the extension of B. xylophilus in a case of an introduction.  相似文献   

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Coniferous wood imported from the Asian part of Russia was surveyed in Germany (Mukran ferry terminal, highway and railway border station in Frankfurt/Oder) and Austria (railway in Marchegg, Retz and Wr. Neustadt, Lower Austria). The consignments consisted of mixed timber of Pinus/Picea or Pinus/Larix. Out of 625 samples investigated, 51 samples (8.5%) yielded eight Bursaphelenchus species. Bursaphelenchus mucronatus was found 42 times in Pinus, Picea and Larix wood, Bursaphelenchus hylobianum and Bursaphelenchus fraudulentus were detected twice, in Pinus/Larix and in Larix, respectively. The following species were each found once: Bursaphelenchus leoni in mixed timber of Pinus/Picea, Bursaphelenchus ‘borealis’ in Pinus, Bursaphelenchus hellenicus and Bursaphelenchus paracorneolus in Larix. One sample of Larix wood from Krasnoyarsk region contained a few specimens corresponding to Bursaphelenchus xylophilus. Bursaphelenchus mucronatus was present in about 30% of the samples showing signs of insect attack. A Monochamus species was found in a sample from Irkutsk. Most of the B. mucronatus isolates found belonged to the European genotype, whereas the East Asian genotype was found in three instances. This is the first report of B. fraudulentus, B. hellenicus, B. leoni, B. paracorneolus and the East Asian genotype of B. mucronatus in Russia. Bursaphelenchus hylobianum is the only species found in Russian wood and not in Europe so far. The species were identified morphologically and by internal transcribed spacer (ITS)‐restriction fragment length polymorphism (RFLP) technique. Species‐specific ITS‐RFLP patterns were established for B. hylobianum. In the case of the isolate morphologically corresponding to B. xylophilus, DNA extraction from the available low number of specimens failed to yield sufficient rDNA for ITS‐RFLP analysis.  相似文献   

15.
Bursaphelenchus willibaldi, associated with trees in two separate locations in forests of northern Iran, are characterized and illustrated based on morphological, morphometric and molecular data. The Iranian population of B. willibaldi has a body length of 392–595 μm, stylet length of 12–14 μm, c‐index of 9.0–14.5 and PUS length of 51–82 μm. Males have spicules 15–18 μm long along the arch line. The Iranian population showed morphometric variations compared with the originally described samples. For example, it has a shorter body in females and males, greater c‐index, slightly greater range of V, slightly smaller range of PUS and tail length. Molecular phylogenetic analysis of the recovered populations revealed both sequenced isolates forming a clade with one European isolate of the species using Bayesian inference (BI) analysis with full Bayesian posterior probability (BPP).  相似文献   

16.
An overview of the genus Bursaphelenchus in the Czech Republic is presented, based on a recent survey for monitoring the presence of the pinewood nematode, Bursaphelenchus xylophilus, as well as on previous reports of this genus in the country. In addition, we provide a morphological and molecular characterization of four Bursaphelenchus species (B. eremus, B. pinophilus, B. vallesianus and B. borealis) found during the monitoring programme for forest pests, conducted during 2006–2010, within the Moravian and Bohemian regions. Nematodes were extracted from over 1917 insects and 1493 wood samples collected from deciduous and coniferous trees exhibiting wilting and declining symptoms. Bursaphelenchus species were found only in 0.73% of insects and 0.47% of the total number of wood samples. Bursaphelenchus borealis and B. pinophilus dauer juveniles were found associated with the insect vectors Dryocetes autographus and Pityogenes bidentatus, respectively. While a total of seven Bursaphelenchus species are now reported from the Czech Republic, the status of B. xylophilus remains as absent.  相似文献   

17.
Bursaphelenchus mucronatus Mamiya et Enda has been recovered for the first time from adults of the cerambycid beetle, Monochamus urussovi (Fischer), in Hokkaido, Japan. The nematode was also recovered from the inner bark of Picea jezoensis (Siebold et Zuccarini) Carrière and Abies sachalinensis (Fr Schmidt) Masters infested with M. urussovi larvae. PCR–RFLP analysis indicated that B. mucronatus in Hokkaido is the European type.  相似文献   

18.
研究-80℃下松材线虫的冷冻保存方法,比较不同冷冻保护剂对松材线虫低温保存的保护效果,以及解冻后松材线虫的繁殖情况。结果表明:15%甘油对松材线虫保护效果最好,解冻后存活率达36.5%,其次为10%甘油、20%甘油、25%甘油,保护效果最差的是1%二甲基亚砜(DMSO);解冻后线虫能够正常生长繁殖,冻存3天和冻存30天的线虫存活率和繁殖无显著性差异。  相似文献   

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首次对松材线虫病在信阳市的传播和扩散风险以及对信阳林业生产和生态环境的危害进行分析,提出信阳市松材线虫病的防控策略,将会有助于信阳各级林业主管部门对该病害进行有效地防治。  相似文献   

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