黄瓜褐斑病（Corynespora cassiicola）在广东首次报道     

蓝国兵  谭耀华  何自福  罗方芳  梁丽欢  虞皓 《植物保护》2012,38(5):197-199

2011年5月和8月,在广东省高要市和增城市黄瓜主产区发现黄瓜褐斑病,致病性测定、形态学观察和rD-NA-ITS序列分析结果表明,引起广东黄瓜褐斑病的病原菌为多主棒孢霉(Corynespora cassiicola)。本文是多主棒孢霉在广东引起黄瓜褐斑病的首次报道。  相似文献   

芝麻细菌性青枯病病原菌及其生化变种鉴定   总被引：3，自引：2，他引：1  

华菊玲  胡白石  李湘民  黄瑞荣  刘光荣 《植物保护学报》2012,39(1):39-44

芝麻细菌性青枯病是我国南方芝麻生产上的重要病害。调查研究表明,芝麻青枯病除前人报道的萎蔫、顶梢常有溃疡裂缝等典型症状外,还有植株畸形、茎秆表皮泡状突起、溃疡裂缝延伸至茎秆中下部、折断茎秆可见菌脓形成的透明细丝等症状。分离获得的病原菌菌株经菌体形态、菌落形态、培养性状、致病性、烟草过敏性反应及16S rRNA基因和16S～23S rRNA基因间区ITS序列测定,证实了芝麻青枯病是由青枯菌Ralstonia solanacearum引起。江西省15个县(市)的22个代表性菌株的生化变种鉴定显示,20株菌属于生化变种Ⅲ,占90.91%,2株属于生化变种Ⅳ,占9.09%。说明生化变种Ⅲ菌群是诱发芝麻青枯病流行的优势种群。  相似文献   

植物与病原菌互作理论研究进展     

韩长志 《河南农业科学》2012,41(11):5-8

植物病原菌与其寄主相互作用过程中,关于病原菌操控植物和植物又反抗病原菌侵染的作用机制,学术界存在多种模型和假说,从最早的Flor"基因对基因"假说到警戒假说,再从警戒假说到"诱饵"假说,再到目前学术界较为认同的Zigzag理论。对这些植物与病原菌互作理论进行了总结,着重介绍了"诱饵"假说和Zigzag理论。  相似文献   

大蒜抗叶枯病变异系的离体筛选及其抗性分析     

程智慧  牛青  孟焕文 《西北农林科技大学学报(自然科学版)》2012,40(2):109-115

【目的】利用病菌粗毒素离体筛选大蒜抗叶枯病变异系,建立抗病变异系离体筛选方法。【方法】以蒜瓣茎盘为外植体诱导愈伤组织;以大蒜叶枯病菌培养滤液制取的粗毒素为筛选剂,离体筛选大蒜抗叶枯病变异系;通过接种病菌粗毒素和病菌孢子鉴定变异株的抗病性,分析变异株的防御酶活性。【结果】大蒜叶枯病菌粗毒素对大蒜愈伤组织增殖有显著抑制作用,抑制作用随病菌粗毒素质量分数的增加而增强,不同大蒜品种愈伤组织对病菌粗毒素的抗性不同;利用不同体积分数的病菌粗毒素分步筛选分别获得大蒜品种G039变异系苗12株,G073变异系苗2株,它们对大蒜叶枯病菌粗毒素具有稳定的抗性。经病菌孢子悬浮液接种鉴定,变异系苗较其对照抗病性提高。大蒜抗叶枯病变异系苗接种病菌后叶片过氧化物酶（POD）、多酚氧化酶（PPO）和苯丙氨酸解胺酶（PAL）的活性在短时间内即达到峰值,且与抗病品种G064接近或更高,而感病品种G039的酶活性则明显低于前两者。【结论】利用不同体积分数的大蒜叶枯病菌粗毒素分步筛选可以获得大蒜抗叶枯病变异系,适宜大蒜抗叶枯病变异系分步筛选的上限粗毒素体积分数为30%;POD、PPO和PAL活性可作为大蒜抗叶枯病鉴定的生化指标。  相似文献   

草原放牧肉牛发生跛行病因分析与防治试验     

黄国成  李志明  胡明  宗泽君  赵瑞霞  红敏  韩天龙  马德林  王振学 《中国兽医杂志》2012,48(2):33-35

赤峰市巴林右旗索博日嘎镇草原放牧的肉牛大面积发生异嗜和跛行症状,经流行情况调查、牧草钙磷营养分析、血清钙磷含量测定、防治试验和大群防治结果表明,是由于严重干旱导致草场上牧草中磷含量降低,钙、磷比例严重失调,造成放牧肉牛矿物质营养缺乏性代谢病.放牧肉牛异嗜发病率平均为33.70％,其中哺乳母牛出现跛行症状的占群体的11.31％.采取以增磷为主的增磷补钙措施进行防治,迅速控制了病情的发展,群体防治总有效率达98.50％.  相似文献   

Genetic analyses of pathogen-specific mastitis     

Holmberg M  Fikse WF  Andersson-Eklund L  Artursson K  Lundén A 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2012,129(2):129-137

The aims of this study were to investigate the presence of genetic variation for susceptibility to pathogen-specific mastitis and to examine whether haplotypes of an identified quantitative trait locus with effect on unspecific mastitis resistance had different effects on specific mastitis pathogens. Bacteriological data on mastitis pathogens were obtained from the diagnostic laboratory at the Swedish National Veterinary Institute. The data were mainly from subclinical cases of mastitis but also clinical cases were included. Variance components were estimated for incidence of the six most frequent pathogens using Markov Chain Monte Carlo methodology via Gibbs sampling. Genetic variation for susceptibility to pathogen-specific mastitis was higher compared to estimates of general resistance to clinical mastitis in most other studies. However, because of the non-random nature of data collection, comparisons to other studies should be made by caution. The effect of haplotype on the risk of being infected by a given mastitis pathogen, relative to other pathogens, was studied using an allele substitution model. Although there were no significant haplotype substitution effects on the resistance to any of the six mastitis pathogens, there was a significant difference between the effects of two of the haplotypes regarding the risk of acquiring a Streptococcus dysgalactiae infection.  相似文献   

副猪嗜血杆菌外膜蛋白表型分析     

朱必凤  杨旭夫  彭凌  韦昭玉 《兽医大学学报》2012,(11):1656-1661,1668

采用SDS-PAGE测定了82个副猪嗜血杆菌分离株细胞外膜蛋白（OMP）,比较不同临床背景分离株的OMP表型差异,分析了OMP与毒力菌株的相关性。结果表明,外膜蛋白分为3种类型：PAGEⅠ、PAGEⅡ和PAGEⅢ型。约34％患病猪分离株属于PAGEI型,只有约9％健康猪分离株属于PAGEI型,说明36000-40000蛋白与菌株的毒力相关。  相似文献   

冀东地区奶牛隐性乳房炎病原菌的分离鉴定     

高桂生  高光平  邵新华  史秋梅  张艳英  梁银聚 《中兽医医药杂志》2012,31(4):17-19

通过LMT法、乳汁pH检验法和体细胞直接计数等方法相结合,对冀东地区3个大型奶牛场、8个奶牛养殖户选取的1 021头奶牛进行隐性乳房炎流行病学调查与病菌分离鉴定。结果表明,隐性乳房炎发病率为60.63%(619/1021),乳房炎阳性乳样品中细菌分离率达88.21%(546/619)。从543头隐性乳房炎患牛的阳性乳区乳样中分得细菌共4类14种菌82株,其中葡萄球菌36株,占43.90%;链球菌33株,占40.24%;肠杆菌类8株,占9.76%;棒状杆菌5株,占6.10%。冀东地区奶牛隐性乳房炎主要病原菌为金黄色葡萄球菌和无乳链球菌。  相似文献   

Influence of maternal immunity on vaccine efficacy and susceptibility of one day old chicks against Egyptian highly pathogenic avian influenza H5N1     

Abdelwhab EM  Grund C  Aly MM  Beer M  Harder TC  Hafez HM 《Veterinary microbiology》2012,155(1):13-20

In Egypt, continuous circulation of highly pathogenic avian influenza (HPAI) H5N1 viruses of clade 2.2.1 in vaccinated commercial poultry challenges strenuous control efforts. Here, vaccine-derived maternal AIV H5 specific immunity in one-day old chicks was investigated as a factor of vaccine failure in long-term blanket vaccination campaigns in broiler chickens. H5 seropositive one-day old chicks were derived from breeders repeatedly immunized with a commercial inactivated vaccine based on the Potsdam/H5N2 strain. When challenged using the antigenically related HPAIV strain Italy/98 (H5N2) clinical protection was achieved until at least 10 days post-hatch although virus replication was not fully suppressed. No protection at all was observed against the Egyptian HPAIV strain EGYvar/H5N1 representing a vaccine escape lineage. Other groups of chicks with maternal immunity were vaccinated once at 3 or 14 days of age using either the Potsdam/H5N2 vaccine or a vaccine based on EGYvar/H5N1. At day 35 of age these chicks were challenged with the Egyptian HPAIV strain EGYcls/H5N1 which co-circulates with EGYvar/H5N1 but does not represent an antigenic drift variant. The Potsdam/H5N2 vaccinated groups were not protected against EGYcls/H5N1 infection while, in contrast, the EGYvar/H5N1 vaccinated chicks withstand challenge with EGYvar/H5N1 infection. In addition, the results showed that maternal antibodies could interfere with the immune response when a homologous vaccine strain was used.  相似文献   

贡柑黑腐病病原菌的分子鉴定     

覃旭  邓明学  阳廷密  谭有龙  张素英  门友均  唐明丽  张戈壁 《中国南方果树》2012,41(2):10-13

贡柑黑腐病是近年来在贡柑上发生的一种新型病害,该病害可导致嫩梢快速枯死,大量嫩叶脱落,严重影响树势和产量。本研究从病区采集发病枝叶,对贡柑黑腐病病原菌进行分离、纯化,并采用rDNA-ITS序列分析技术对其进行分子鉴定。结果表明,贡柑黑腐病病原菌为链格孢属Alternaria Nees真菌,rDNA-ITS序列与GenBank中芸薹链格孢菌A.brassicae(Berk.)Sacc.和柑桔链格孢菌A.citri Ellis et Everhart的ITS序列的同源性为99%。结合形态学特征,推断该病原菌为柑桔链格孢菌。  相似文献