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内蒙古马铃薯黑胫病病原菌的分离和鉴定 总被引：2，自引：1，他引：1
马铃薯是我国的第四大主粮。内蒙古是我国最大的马铃薯生产基地,马铃薯产业是当地农民收入的主要来源。2017年8月,内蒙古锡林郭勒盟部分马铃薯田块发生了一种细菌性黑胫病,发病面积约为200亩,发病率约为20%。发病初期,植株的茎基部变色、发黑,伴有臭味,严重时茎秆腐烂,植株死亡。为明确该地区马铃薯细菌性黑胫病的病原菌种类,本研究对该病原菌进行了分离,并利用生理生化测定,Biolog分析和分子生物学手段将该病原菌鉴定为胡萝卜软腐果胶杆菌巴西亚种(Pectobacterium carotovorum subsp. brasiliense)。据以往报道,我国马铃薯黑胫病主要由黑腐果胶杆菌(P. atrosepticum)和胡萝卜软腐果胶杆菌胡萝卜亚种(P. carotovorum subsp. carotovorum)两种病原菌引起,本研究是P. carotovorum subsp. brasiliense引起马铃薯黑胫病在国内的首次报道。 相似文献
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烟草黑胫病菌对农田草本植物的寄主范围 总被引：1，自引：0，他引：1
烟草黑胫病是烟草生产中的重要病害,对烟草的产量和质量均影响极大[1-2]。烟草黑胫病菌Phytophthora nicotianae var.nicotianae（Breda deHaan）Tucker是引起烟草黑胫病的唯一病原菌,以往的研究均认为, 相似文献
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为获得对烟草黑胫病（tobacco black shank）具有较好拮抗作用的菌株,从食腐昆虫美洲大蠊Periplaneta americana肠道分离纯化得到1株对烟草黑胫病具有较强抑制作用的D5-8菌株,拟进一步明确该菌株的分类地位,优化其发酵条件并测定其对烟草黑胫病的防治效果。利用形态特征、生理生化特性观察及16S rRNA基因序列分析对D5-8菌株进行鉴定;以细菌发酵液OD600值及对病原菌的抑制率为指标,对其发酵培养基和发酵条件进行单因素试验及正交试验;通过室内盆栽试验,明确菌株D5-8对烟草黑胫病的防治效果。结果表明,经平板对峙试验发现菌株D5-8对烟草寄生疫霉的抑制率达66.80%;通过形态特征和生理生化特征初步确定菌株D5-8为芽胞杆菌属Bacillus,结合16S rRNA基因序列分析鉴定菌株D5-8为特基拉芽胞杆菌Bacillus tequilensis;其最适培养基：牛肉浸膏8 g,酵母浸粉5 g,麦芽糖10 g,蒸馏水1000 mL;最佳的发酵条件为温度28℃、初始pH 6、转速210 r/min、装液量30 mL、接种量2%、培养时间60 h、光照时间4 h;盆栽试验结果表明,发酵条件优化后D5-8发酵液（108cfu/mL）对烟草黑胫病的保护防效和治疗防效可达66.89%和53.72%,均高于原始发酵液的61.84%和51.83%。研究结果为特基拉芽胞杆菌D5-8生防菌剂的开发及其对烟草黑胫病的防治应用提供了理论依据。 相似文献
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为获得对烟草黑胫病和根黑腐病具有双重防病效果且能够促进烟草生长的假单胞杆菌,采用稀释涂布法从40份土壤样品中分离出201株细菌,通过平板对峙和含毒介质法,筛选出对烟草黑胫病和烟草根黑腐病病原菌均具有良好拮抗作用的菌株PA2101和PG3402。盆栽促生试验表明,菌株PA2101和PG3402能协调地改善烟草地上部分的生长和烟草根系发育,均在一定程度上增加了烟草的株高、叶面积、株鲜重、根鲜重、叶片数和根长,提高了烟草的根冠比和根活力。盆栽试验结果表明,菌株PA2101对烟草黑胫病和根黑腐病的防效分别为70.11%和62.67%,均高于其对照药剂;菌株PG3402对两种病害的防效分别为60.92%和60.00%,与对照药剂相当。抗性标记菌株的定殖试验结果表明,菌株PA2101和PG3402在接种后第29 d能定殖于烟草根际土壤和根内,在烟草茎和叶内也能长时间存在,表明两菌株能够良好定殖。16Sr DNA序列、菌落形态和生理生化性状分析表明,菌株PA2101为铜绿假单胞杆菌Pseudomonas aeruginosa,菌株PG3402为格拉纳达假单胞杆菌Pseudomonas granadensis。综上所述,菌株PA2101和PG3402对烟草具有良好的促生作用,并对烟草黑胫病和根黑腐病有较好的防病效果,是具有生防潜力的菌株。 相似文献
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拮抗细菌B8对烟草黑胫病菌的抑制作用及其菌株鉴定 总被引：11，自引：0，他引：11
从烟草根际土壤中分离到对烟草黑胫病菌及其它植物病原菌具有抑制作用的菌株B8,平板对峙培养抑菌带内菌丝畸形、原生质凝集或外渗。其发酵原液和发酵液的无菌滤液均能抑制烟草黑胫病菌和蜡状芽孢杆菌;离体叶片接种法测定其发酵液对烟草黑胫病的防效,结果表明预防作用达100%。室内盆栽试验表明B8菌株发酵液对烟草黑胫病的预防作用可达78.1%,优于治疗作用。该菌菌体杆状,芽孢侧生、椭圆形,经形态学、生理生化性状和16S rDNA序列测定,将其鉴定为侧孢短芽孢杆菌。 相似文献
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<正>Dickeya和Pectobacterium属细菌的植物寄主广泛,包括十字花科、茄科、百合科、伞形花科和禾本科等科的农作物[1],所引发的细菌性软腐病严重影响农作物的产量和品质,造成严重经济损失,威胁农业生产和粮食安全。Dickeya和Pectobacterium属不同种的菌株能侵染同一种植物,产生相似的病症。如已发现能侵染马铃薯并导致软腐病害的有D. solani、D. dianthicola、D. dadantii、D.chrysanthemi、D. zeae、P. versatile、P. carotovorum、P. brasiliense、P. atrosepticum、P. betavasculorum、P. parmentieri、P. parvum、P. peruviense、P. polaris、P. actinidiae和P. punjabense等种的细菌[2-3]。 相似文献
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马铃薯枯萎病是马铃薯主要土传真菌病害之一,已成为限制我国马铃薯产业健康发展的重要因素之一。菌株ZF128是本实验室从马铃薯根际土壤分离筛选得到的一株对马铃薯枯萎病菌具有显著抑制效果的生防细菌。经生理生化、BIOLOG GENIII和系统发育树分析,鉴定菌株ZF128为贝莱斯芽胞杆菌Bacillus velezensis。抑菌谱测定结果显示,ZF128对5种病原真菌和5种病原细菌都具有显著拮抗效果。光学显微观察发现,菌株ZF128处理的病原菌菌丝生长受到抑制并出现膨胀变粗现象。发酵试验表明,菌株ZF128在甘露醇培养基中发酵上清液对马铃薯枯萎病菌的抑制效果最好。盆栽试验结果证明,接种菌株ZF128后马铃薯发病明显减轻,防效为82.46%。此外,定殖和促生试验表明,菌株ZF128能在马铃薯根际和根部有效定殖30d以上,处理组马铃薯株高、根长、地上部和地下部鲜重及叶绿素含量等指标均显著高于对照组。综上,菌株ZF128生防性状优良,是一株具有潜在应用价值的芽胞杆菌。 相似文献
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P. Skelsey J. G. Elphinstone G. S. Saddler S. J. Wale I. K. Toth 《Plant pathology》2016,65(4):570-576
Potato blackleg, caused by Pectobacterium and Dickeya species, is one of the most significant bacterial diseases affecting potato production globally. Although it is generally accepted to be a seedborne disease, the processes underlying the spread of disease largely remain unknown. Spatial point pattern analysis was applied to blackleg occurrence in seed potato crops in Scotland during the period of 2010–2013 (approximately 8000 blackleg‐affected crops), to assess whether its distribution was random, regular or aggregated, and the spatial scales at which these patterns occurred. Blackleg‐affected crops derived from mother stocks with symptoms were omitted from the analyses in order to examine the statistical evidence for horizontal transmission of blackleg. The pair correlation function was used to test for global spatial autocorrelation, and results indicated significant (P < 0·05) clustering of incidence at a wide range of spatial scales. Strength of clustering (degree of aggregation) among blackleg‐affected crops was notably larger at spatial scales of 25 km or less. A hot‐ and coldspot analysis was performed to test for local spatial autocorrelation, and statistically significant clusters of high and low values of disease were found across the country. These analyses provide the first quantitative evidence of localized and large‐scale spatial clustering of potato blackleg. Understanding the mode(s) of inoculum dispersal will be important for developing new management strategies that minimize host–pathogen contacts in potato and numerous other crops affected by pathogenic Pectobacterium and Dickeya species. 相似文献
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Pectobacterium atrosepticum, P. carotovorum subsp. brasiliensis, P. carotovorum subsp. carotovorum, and P. wasabiae were detected in potato stems with blackleg symptoms using species- and subspecies-specific polymerase chain reaction (PCR). The tests included a new assay for P. wasabiae based on the phytase gene sequence. Identification of isolates from diseased stems by biochemical or physiological characterization, PCR, and multi-locus sequence typing (MLST) largely confirmed the PCR detection of Pectobacterium spp. in stem samples. P. atrosepticum was most commonly present but was the sole Pectobacterium sp. detected in only 52% of the diseased stems. P. wasabiae was most frequently present in combination with P. atrosepticum and was the sole Pectobacterium sp. detected in 13% of diseased stems. Pathogenicity of P. wasabiae on potato and its capacity to cause blackleg disease were demonstrated by stem inoculation and its isolation as the sole Pectobacterium sp. from field-grown diseased plants produced from inoculated seed tubers. Incidence of P. carotovorum subsp. brasiliensis was low in diseased stems, and the ability of Canadian strains to cause blackleg in plants grown from inoculated tubers was not confirmed. Canadian isolates of P. carotovorum subsp. brasiliensis differed from Brazilian isolates in diagnostic biochemical tests but conformed to the subspecies in PCR specificity and typing by MLST. 相似文献
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M. C. M. PÉROMBELON Y. BERTHEAU M. CAMBRA D. FRECHON M. M. LOPEZ F. NIEPOLD P. PERSSON A. SLETTEN I. K. TOTH J. W. L. VAN VUURDE J. M. VAN DER WOLF 《EPPO Bulletin》1998,28(1-2):141-155
Contamination of seed potato tubers by Erwinia carotovora subsp. atroseptica is widespread with the bacteria usually sited superficially in lenticels and suberized wounds. As seed contamination level is related to blackleg incidence, seed health is best assessed by determining the number of cells of E. c. atroseptica per mL of tuber-peel extract. The relative specificity, sensitivity and ease of use of four recently developed microbiological, immunological and molecular methods to detect and/or quantify tuber contamination are discussed in relation to the testing of commercial seed stock. Sensitivities of all four methods are at or below the threshold level for blackleg development (< 103 cells mL-1 ), but there are differences regarding their specificity and ease of use. Three of them allow enumeration of most live cells of the bacterium, using specific monoclonal and polyclonal antibodies against the predominant serogroup I: (a) immunomagnetic separation of E. c. atroseptica before viable count on a selective-diagnostic growth medium, crystal violet pectate, (b) immunofluorescence staining and counting of colonies in pour-plate medium in tissue culture plates and (c) enrichment of the bacterium in peel-extract dilutions directly in microtitre plates prior to DAS-ELISA. In the fourth method, both live and dead cells are detected, but not quantified, by PCR amplification of target sequences using specific primers for E. c. atroseptica regardless of serogroup. 相似文献
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Elizabeth Ngadze Carrie L. Brady Teresa A. Coutinho Jacquie E. van der Waals 《European journal of plant pathology / European Foundation for Plant Pathology》2012,134(3):533-549
Soft rot and blackleg can cause severe economic losses in potato production in South Africa and Zimbabwe depending on climatic conditions. The aim of the study was to identify the predominant bacteria causing potato soft rot and blackleg in these countries. Samples, comprising of stems and tubers from potato plants with blackleg and soft rot symptoms were collected from 2006?C2009 from potato production areas where disease outbreaks occurred. The isolates from these plants and tubers yielded Gram negative, pectinolytic bacteria on crystal violet pectate and inoculated tubers. Identification was based on biochemical and phenotypic characteristics, rep-PCR, Amplified Fragment Length Polymorphisms and sequences of gyrB and recA genes. Isolates from Zimbabwe were identified as Pectobacterium carotovorum subsp. brasiliensis (Pcb) (21 isolates), Dickeya dadantii subsp. dadantii (Dd) (20 isolates), P. c. subsp. carotovorum (Pcc) (16 isolates) and P. atrosepticum (Pa) (4 isolates). Pcb, Pcc and Dd subsp. dadantii were isolated from samples collected from all the regions, while Pa was isolated from Nyanga the coolest region in Zimbabwe. In South Africa, however, Pcb was the most common causal agent of soft rot and blackleg. P. atrosepticum was the only pathogen isolated from samples collected in Nyanga, Zimbabwe, and was not isolated from any South African samples. AFLP analysis separated the Pcb strains into 12 clusters, reflecting subdivision in terms of geographic origin, and Pcc isolates were clearly differentiated from Pcb isolates. A large degree of DNA polymorphism was evident among these 12 clusters. The study identified all the pathogens associated with the blackleg/soft rot disease complex. 相似文献
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Johanna J. van der Merwe Teresa A. Coutinho Lise Korsten Jacqueline E. van der Waals 《European journal of plant pathology / European Foundation for Plant Pathology》2010,126(2):175-185
In South Africa during the 2006/2007 potato growing season, outbreaks of blackleg occurred, causing severe economic losses
in commercial potato production fields. Symptoms were initially observed on only one stem per plant, on which the top leaves
rolled upwards, wilted and became necrotic. As symptoms progressed to the lower leaves with subsequent leaf desiccation, a
light to dark brown discolouration of the vascular system at the stem base developed, followed by external darkening. Under
prevailing wet and humid conditions stems became slimy and pale. In the stems, the pith became necrotic and hollow. These
symptoms were similar to those described in Brazil, where the causal agent was identified as a new subspecies, Pectobacterium carotovorum subsp. brasiliensis (Pbcb). Isolations from plants showing typical blackleg symptoms were made on CVP medium. Sequences and phylogenetic analysis of
the partial 16S–23S rDNA intergenic spacer region indicated that the isolates were Pbcb. Comparison of PCR-RFLP patterns of the 16S–23S rDNA of isolates to reference cultures confirmed the identity of the South
African blackleg strains as Pbcb, identical to strain 8 isolated in Brazil. This is the first report of Pbcb in South Africa and it appears to be the most important causal agent of blackleg in South Africa. The disease poses a major
potential threat to the South African potato industry especially in terms of seed exports, tuber quality and yield. 相似文献
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马铃薯黄萎病是一种重要的世界性土传兼种传维管束病害,危害大且防治困难。利用活体微生物杀菌剂是防治作物土传病害的有效措施之一。本研究通过盆栽试验评价了微生物杀菌剂枯草芽胞杆菌可湿性粉剂对马铃薯出苗和生长的安全性,在河北省马铃薯主产区开展田间小区试验,研究了该制剂有效防治马铃薯黄萎病的使用方法和适宜施用剂量,并在河北省涞源县、围场县和永年区3县区分别开展了田间示范应用。盆栽试验和田间试验结果表明,枯草芽胞杆菌可湿性粉剂15、30和45 kg/hm2拌种处理对马铃薯出苗安全,对马铃薯生长没有不良影响;田间小区试验表明,在围场县试验田中,该制剂30 kg/hm2拌种处理单独使用或30 kg/hm2拌种加15 kg/hm2初花期滴灌使用均能显著减轻马铃薯黄萎病的发生,分别增产15.53%和17.10%;在新乐市试验田,枯草芽胞杆菌可湿性粉剂30 kg/hm2拌种处理显著增加马铃薯产量16.38%。田间示范应用结果表明,枯草芽胞杆菌可湿性粉剂30 kg/hm2拌种处理在涞源县和围场县防治马铃薯黄萎病效果显著,防效分别为84.22%和72.93%,两地分别显著增产24.30%和9.27%;在邯郸市永年区,相比化学药剂对照处理,枯草芽胞杆菌可湿性粉剂30 kg/hm2拌种处理显著增加马铃薯产量19.73%。本研究表明,枯草芽胞杆菌可湿性粉剂对马铃薯黄萎病具有显著的防治效果和显著的增产效果,为该制剂在马铃薯生产中高效应用提供了科学依据。 相似文献