上海地区种植的21个番茄品种抗细菌性溃疡病的鉴定

番茄溃疡病是由密执安棒形杆菌密执安亚种引起的番茄最具毁灭性病害之一,选育和种植抗耐病品种是防治该病最经济有效的防治手段。本研究收集上海种植的21个番茄品种进行温室育苗,在苗期和成株期分别采用打顶法接种进行抗病性测定。分级调查病情,根据病情指数划分反应型,确定供试品种的抗感类型。在供试的21个番茄品种中,只有欧宝318、粉丽、浙粉202和世纪粉冠王表现为中度感病,其余全为高感品种,没有免疫、抗病或耐病品种。     

东北地区番茄细菌性溃疡病的发生和病原鉴定研究

 1988~1989年从北京市、辽宁和黑龙江省等地调查采集的患溃疡病的病株和病果上分离到17个细菌菌株,接种番茄幼苗、果实及叶片,均能产生典型的溃疡病症状,各菌株致病力无明显差异。各菌株经细菌染色反应,形态特征,培养性状,生理生化反应,血清学反应(ELISA法)及蛋白质凝聚丙烯酰胺胶电泳等鉴定,认为番茄溃疡病的病原细菌是:密执安棒杆菌密执安亚种(Clavibacter michiganense subsp.michiganense (Smith) Davies et al.)。试验表明病原细菌可经种子带菌传染,病残体和病土壤可能是初侵染菌源。抗病性测定45个番茄品种均属感病品种。寄主范围除番茄外,尚能侵染茄子、龙葵和心叶烟。     

番茄溃疡病鉴定研究

1985年7月在北京市发现番茄溃疡病,其病原细菌为Clavibacter michiganense subsp.michiganense,这个病害在国内未曾正式报道。寄主植物除番茄外,尚可侵染其它茄属植物。该病害为害严重,随种子传播蔓延,我国已列为危险性检疫病害。从病株和病果实上分离到病原细菌,其培养和生化性状与标准菌株完全一致。蘸根法接种番茄幼苗,7天后出现典型萎蔫症状。有较强的致病力。     

番茄溃疡病一步法快速超灵敏检测技术研究

对种子携带的番茄细菌性溃疡病菌(Clavibacter michiganensis subsp,michiganensis)进行简单抽提和纯化,不经过DNA提取而以病原菌为模板直接进行一步法PCR检测,对纯菌液Direct-PCR最低检出限为2600个细菌/mL,而Nested-PCR最低检出限可达到13个细菌/mL;对种子提取液,Direct-PCR不能检出,而Nested-PCR最低检出限可达到3×105个细菌/mL.一步法Nested-PCR可在12h内对番茄种子携带的番茄溃疡病菌进行准确的定性鉴定.并且方法方便快速,成本低,灵敏度高,适用于种子携带番茄溃疡病菌的快速鉴定.     

猕猴桃品种对细菌性溃疡病的抗性机制

研究了安徽省猕猴桃主栽品种金魁(高抗)、早鲜(中抗)、魁蜜(抗病)、华美2号(感病)、秦美(中感)和金丰(高感)对细菌性溃疡病的抗性机制.结果表明:形态结构抗性方面,感病品种的皮孔密度和长度及气孔密度、长度和宽度都明显高于抗病品种,抗、感品种间皮孔、气孔的排列方式也存在一定差异.相关分析表明,皮孔密度和长度及气孔密度、长度和宽度与品种发病率都有较高的相关性,尤其以皮孔长度和气孔长度相关性最高,r分别为0.9278和0.9794;生理生化抗性方面,品种未感染溃疡病菌前,芽中的POD酶活性与品种抗性存在规律性不强,一年生枝条、叶片中的POD酶活性与品种抗性有密切关系.品种感染溃疡病菌后,POD酶活性均升高,但抗病品种中酶活提高倍数高于感病品种.一年生枝条上病斑越大,POD酶活性越高.POD同工酶谱带表现出与酶活相一致的规律.     

种传番茄溃疡病菌直接PCR和免疫捕捉PCR检测方法之比较

用PBS和种子研磨后的普通病原提取液稀释番茄溃疡病菌纯菌液,并以梯度纯菌液和带菌种子提取液作为模板进行直接PCR和免疫捕捉PCR,比较2种方法在纯菌液和带菌种子提取液中的检测灵敏度,找到一种高特异性、高灵敏度、简便快捷的方法用于检测番茄种子携带的番茄溃疡病菌。结果显示在纯菌液中直接PCR灵敏度为104cfu/mL,免疫捕捉PCR为102cfu/mL;在带菌种子提取液中直接PCR灵敏度为106cfu/mL,免疫捕捉PCR为104cfu/mL;免疫捕捉PCR比直接PCR灵敏度高100倍,尤其在实际种子检测中优势更明显,而且检出时间短,重复性好。     

棚室番茄溃疡病的综合防治技术探讨

采取选用抗病品种,实施种子检疫、种子处理、棚室及土壤消毒防病以及栽培措施防病和化学药剂防病等综合防治手段,是预防和治疗番茄溃疡病的有效途径。发病株率可控制在7.5%以下。     

番茄细菌性溃疡病的生态学和防治及其病原体的检测方法

当番茄叶片上的病原菌〔Claribacter michiganensis 的亚种(ssp.) michiganensis〕种群密度高于10~6cfu/g时,细菌性溃疡病就发生;而种群密度低于10~3～10~5cfu时则不会发生。在露地降雨条件下有利细菌增殖和传播,使病害加重。在塑料大棚下栽培番茄,是防治其细菌性溃疡病的可行方法之一。SMCMM培养基可用于该病害的生态学研究,而ELISA可对该致病菌(C.m.ssp.michiganensis)进行检测及快速诊断其所致病害。     

番茄溃疡病疫情监测与防控技术

本文描述了番茄溃疡病发病症状、病菌形态及特点、致病机理,介绍了病原菌分离鉴定方法及当前流行的分子检测技术,同时对番茄溃疡病预防控制提出了方法。     

湘西地区猕猴桃细菌性溃疡病抗性资源筛选及其抗性机理研究

由Pseudomonas syringae pv.actinidiae(Psa)引起的溃疡病是猕猴桃生产中威胁最大的细菌性病害。种植抗病品种是防治猕猴桃溃疡病最有效途径,猕猴桃抗源是抗病育种的物质基础。本试验通过离体接种,在室内评价了4个不同种的7个猕猴桃资源及品种对溃疡病的抗性。结果表明:供试材料离体叶片、枝条接种溃疡病菌后,其发病时间、病斑大小、发病率差异明显。按病斑大小排序,其抗性强弱依次为毛花猕猴桃‘M9808’>对萼猕猴桃‘S9801’>美味猕猴桃‘M-06’>美味猕猴桃‘米良1号’>中华猕猴桃‘Z-12’>中华猕猴桃‘东红’>中华猕猴桃‘红阳’(CK)。其中,毛花猕猴桃‘M9808’抗病性最强,表现为发病最晚,离体叶片、枝条分别于接种后10 d、20 d发病,比对照推迟了8 d、10 d;病斑最小,为对照的1/25、1/11;发病率最低,为对照的1/28、1/10。抗病性相关酶活性比对发现,不同材料的PAL、CAT、POD酶活性差异较大,抗性材料均高于感病材料,且峰值出现时间早于感病材料。其中,毛花猕猴桃‘M9808’的PAL峰值最高,接种后5 d出现,比对照早10 d;CAT、POD峰值接种后10 d出现,比对照早5 d。说明毛花猕猴桃‘M9808’对溃疡病抗性最强,可作为今后猕猴桃抗病育种或抗性砧木的理想材料。这为猕猴桃抗病育种提供了理论依据,为猕猴桃溃疡病的防控提供了参考。     

拮抗菌Z-L-22不同剂型对番茄溃疡病的防治效果

以对番茄溃疡病菌拮抗效果良好的西唐链霉菌(Streptomyces setonii)菌株Z-L-22为研究对象,开发出3种大田应用剂型——水剂、颗粒剂和片剂,确定了片剂最佳发酵组分,并测定不同剂型在温室和棚室对番茄溃疡病的防治效果。温室试验结果表明,10×发酵液稀释液、固体发酵物5g和片剂1g于番茄定植时施用,对番茄溃疡病防效可达到80%以上;棚室番茄定植75d后,经过水剂、颗粒剂、片剂处理后的番茄发病率和严重度均显著低于硫酸链霉素处理和空白对照。其中片剂由于具有成本低、易储存运输、持效期长等优点,有很高的开发价值。     

Effects of nutrient solution pH on the survival and transmission of Clavibacter michiganensis ssp. michiganensis in hydroponically grown tomatoes

The effect of pH on the survival of Clavibacter michiganensis ssp. michiganensis and its transmission via roots of tomato in hydroponic culture was studied in laboratory and greenhouse experiments. In a laboratory experiment, C . m. ssp. michiganensis could not survive for 24 h in nutrient solutions with a pH of 4·0 or 4·5, while 1, 14, 51 and 62% of inoculum survived at pH 5·0, 5·5, 6·0 and 6·5, respectively. When tomato plants were inoculated with C . m. ssp. michiganensis through wounds on the stems, the bacteria moved downward from the inoculation site to the roots and infectious bacteria were released from the roots into the nutrient solution. Of two pH regimes tested in greenhouse nutrient-film technique (NFT) culture, the C . m. ssp. michiganensis population was significantly lower in pH 5·0 than in pH 6·5 in most sampling data. In treatments in which C . m. ssp. michiganensis was introduced by transplanting two root-inoculated plants, significantly more plants developed canker at pH 6·5 (34 out of 48 plants) than at pH 5·0 (11 out of 48 plants). When the bacterium was introduced by transplanting two stem-inoculated plants at pH 6·5, seven out of 24 plants developed canker. The potential of pH manipulation in controlling tomato bacterial canker in hydroponic culture is discussed.     

不同来源番茄溃疡病菌致病力差异研究

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。     

Quantification of viable cells of Clavibacter michiganensis subsp. michiganensis using a DNA binding dye and a real-time PCR assay

Viable cells of Clavibacter michiganensis subsp. michiganensis (CMM), the causal agent of bacterial canker of tomato, were discriminated from the dead cells by quantitative real-time polymerase chain reaction (PCR), after the bacterial solution was treated with the DNA binding dye ethidium monoazide (EMA). The primers and TaqMan probe, based on the 16S-23S rDNA spacer sequences, were highly specific for CMM at the subspecies level. The detection limit of the direct real-time PCR was 10³ colony forming units per mL (cfu mL⁻¹) in samples and with an apparent sensitivity of 2 cfu of target cells in PCR reaction solution. Application of this method allows for selective quantification of viable cells of CMM and facilitates monitoring the pathogen in tomato seeds.     

Susceptibility of Commercial Tomato Cultivars to Bacterial Wilt in Hydroponic System

Commercially available tomato cultivars were hydroponically cultured for inoculation, with Ralstonia solanacearum (K-101), which causes bacterial wilt, by pouring an inoculum suspension into the nutrient solution. Cultivar susceptibility to the bacteria was evaluated, based on the highest percentage of wilting. Because the length of time for wilt appearance varied among cultivars, some cultivars appeared to be suppressive to the translocation and/or multiplication of the invading pathogen. Thus, this hydroponic inoculation system is effective for examining levels of susceptibility in tomato cultivars to bacterial wilt. Received 13 December 2000/ Accepted in revised form 27 March 2001