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水稻细菌性条斑病Xanthomonas campestris pv.oryzicola是国家规定的植物检疫对象。该病发生以后,一般病田可减产10％～20％,重病田可达4～6成。近年来,该病在我国南部稻区呈传播蔓延趋势,已危及水稻生产的安全。尤其在杂交水稻制繁种基地,一旦发现该病,则直接影响水稻种子的使用,其后果更为严重。实践表明,水稻细菌性条斑病可随带病种 相似文献
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辣椒疫霉菌研究概况 总被引：1，自引：0，他引：1
由辣椒疫霉（Phytophthora capsici Leonian）引起的辣椒疫病是一种世界性病害。除危害辣椒外,也可侵染番茄、茄子、黄瓜、西瓜、南瓜等作物。该病于1918年首次在美国被发现,现已遍及世界各地的辣椒种植区。近年随着保护地栽培面积的不断扩大,该病的发生有逐年加重的趋势,在我国青海、新疆、浙江、湖北、上海等10几个省市自治区均有发生。疫病在气候条件适宜的情况下,短期内就可暴发,使辣椒生产遭受严重的经济损失。由于辣椒疫病是多循环的病害,在一个生长季可以发生多次接种体的产生和多次再侵染,因此感病部位接种体的传播在疫病的流行过程中发挥着重要的作用。 相似文献
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云杉落针病Lophodermium piceae（Fuckel）Von Hoehnel是高山林区云杉人工林的一种重要叶部病害,该病在川西高山部分林区人工更新的云杉幼林中发生严重．且有逐年发生面积加大和为害加重的趋势。为有效控制该病的为害蔓延,现介绍该病的发生规律和防治方法。 相似文献
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近年来,随着我国农村产业结构的调整和黄瓜栽培面积的不断扩大,灰霉病已成为黄瓜生产上的一种重要病害。该病由灰葡萄孢菌(Botrytis cinerea)侵染所致,可危害茄子、番茄、辣椒、西葫芦、莴苣、草莓等多种蔬菜。目前,该病在淮安黄瓜产区普遍流行,防治不及时,可减产10%～30%,严重的则达50%以上。 相似文献
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番茄溃疡病菌PCR快速检测技术 总被引：2，自引：0，他引：2
番茄溃疡病是一种严重危害番茄生产的细菌性病害，许多国家将其列为检疫性病害。利用ITS通用引物扩增了番茄溃疡病菌（Clavibacter michiganensis subsp．michiganensis）的ITS序列，并进行克隆测序。根据序列比较结果设计了引物BT1和BT2，该引物特异性好，能专一扩增出268bp电泳条带，而马铃薯环腐病菌等不同亚种、不同属的细菌及健康的番茄材料均无扩增条带。从接种但未显症番茄苗叶片及人工模拟染菌种子上提取总DNA，以此为模板均能稳定地扩增出特异性目的条带。该方法直接对种子或植株进行检测，不需进行病原菌分离培养，快速简便，适用于出入境检验检疫及种苗健康检测领域。 相似文献
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Frida Kleitman Isaac Barash Annette Burger Naim Iraki Yunis Falah Guido Sessa Dan Weinthal Laura Chalupowicz Karl-Heinz Gartemann Rudolf Eichenlaub Shulamit Manulis-Sasson 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(4):463-475
Clavibacter michiganensis subsp. michiganensis (Cmm) strains, collected during the last decade from different locations in Israel, were analyzed by macrorestriction pulsed-field
gel electrophoresis (PFGE). Fifty-eight strains from Israel and 18 from other sources were differentiated into 11 haplotypes
with either VspI or DraI restriction enzymes. The strains from Israel formed four distinct groups among which groups A (16 strains) and B (32 strains)
constituted the major clusters. These two groups originated from the Besor region, which is the main area for growing tomatoes
under cover. Rep-PCR, with either ERIC or BOX primers, confirmed results obtained by PFGE. PCR with primers based on three
genes – ppaA, chpC and tomA – that spanned the pathogenicity island of the reference strain NCPPB382, produced the expected products with the tested
pathogenic strains. Plasmid analysis of representative strains revealed different profiles of one or two plasmids. However
all the strains, including five non-pathogenic ones, reacted positively in PCR with primers based on celA gene, which resides on the plasmid pCM1 of NCPPB382. Southern hybridization of total DNA with a 3.2-kb BglII-fragment of pCM1 containing the celA gene was positive when carried out with 31 strains, but the size of the reacting band was not always the same as that of
pCM1, suggesting that the plasmids carrying celA may differ in size. Comparison between the colonization rates of strain Cmm42 (group A) and of Cmm32 (group B) did not show any significant differences. The high diversity of the Cmm strains, on the one hand, and the presence of two persistent groups in the Besor region, on the other hand, suggests that
the primary inoculum originated each year from residual plants in the soil rather than from infested seeds, in spite of extensive
control measures taken by the growers in this area. 相似文献
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不同来源番茄溃疡病菌致病力差异研究 总被引：1，自引：0，他引：1
采用打顶法接种、半选择性培养基再分离发病植株中的病原菌,以及特异性PCR验证方法,对来自3个国家9个不同地区的46株番茄溃疡病菌进行了致病性测定,以病情指数评价不同菌株的致病力。结果显示,分离自我国河北滦平县、内蒙古包头市等地的24株菌株的病情指数达到75以上,属于强致病力水平;11株菌株的病情指数为50~75,属于中等致病力;而9株菌株的病情指数为50以下,属于弱致病力;检测同时证实,有2株属于无致病力菌株。强致病力、中等致病力、弱致病力和无致病力菌株占供试菌株总数的比例分别为52.2%、23.9%、19.6%和4.3%,表明供试的46株番茄溃疡病菌存在不同程度的致病力差异。 相似文献
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对来自全国若干省市的番茄细菌性溃疡病菌(Clavibacter michiganensis subsp.michiganensis)的33个菌株进行rep-PCR分析。结果表明,用引物BOX分别扩增出6～15条多态性条带,条带大多数集中在500～2800bp之间;用引物ERIC扩增的条带不清晰,可能是反应条件不适合,也可能是其不适合对番茄细菌性溃疡病菌进行多态性分析;BOX-PCR表明番茄细菌性溃疡病菌菌株具有丰富的遗传多态性和较大的遗传变异,对产生的指纹图谱进行分析:在遗传距离为0.18时,测试的33个菌株可划分为Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ和Ⅶ等7个遗传相似组群,其中Ⅵ组群包含的菌株最多。研究还表明番茄细菌性溃疡病菌的遗传分群与菌株的地理来源关系密切,但与该病的发病年份上没有必然联系,这也从另一侧面说明了该病害是土壤带菌引起的。 相似文献
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ABSTRACT Hydathodes of tomato leaves served as extremely efficient infection courts for the bacterial canker pathogen, Clavibacter michiganensis subsp. michiganensis. Chlorotic lesions developed at the tips of leaflet lobes about 2 weeks after inoculation of guttation droplets. Lesions expanded along the leaflet margins and became necrotic. Movement of C. michiganensis subsp. michiganensis from the inoculated leaflet into the rachis was slow and erratic. Histological observations revealed that pathogen populations first developed within large intercellular spaces lying beneath the stomata, which serve as water pores in tomato hydathodes. Bacteria were first observed within vessels of the large marginal fimbriate veins 7 days after inoculation. By 14 days after inoculation, large populations could be seen within the vessels; and by 21 days after inoculation, tissue collapse was widespread and masses of bacteria could be seen in the intercellular spaces and within necrotic cells. 相似文献
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Chalupowicz L Zellermann EM Fluegel M Dror O Eichenlaub R Gartemann KH Savidor A Sessa G Iraki N Barash I Manulis-Sasson S 《Phytopathology》2012,102(1):23-31
The vascular pathogen Clavibacter michiganensis subsp. michiganensis is responsible for bacterial wilt and canker of tomato. Pathogenicity of this bacterium is dependent on plasmid-borne virulence factors and serine proteases located on the chromosomal chp/tomA pathogenicity island (PAI). In this study, colonization patterns and movement of C. michiganensis subsp. michiganensis during tomato infection was examined using a green fluorescent protein (GFP)-labeled strain. A plasmid expressing GFP in C. michiganensis subsp. michiganensis was constructed and found to be stable in planta for at least 1 month. Confocal laser-scanning microscopy (CLSM) of inoculated stems showed that the pathogen extensively colonizes the lumen of xylem vessels and preferentially attaches to spiral secondary wall thickening of the protoxylem. Acropetal movement of the wild-type strain C. michiganensis subsp. michiganensis NCPPB382 (Cmm382) in tomato resulted in an extensive systemic colonization of the whole plant reaching the apical region after 15 days, whereas Cmm100 (lacking the plasmids pCM1 and pCM2) or Cmm27 (lacking the chp/tomA PAI) remained confined to the area surrounding of the inoculation site. Cmm382 formed biofilm-like structures composed of large bacterial aggregates on the interior of xylem walls as observed by CLSM and scanning electron microscopy. These findings suggest that virulence factors located on the chp/tomA PAI or the plasmids are required for effective movement of the pathogen in tomato and for the formation of cellular aggregates. 相似文献
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