海南菠萝一种叶斑病病原菌的分离与鉴定及多基因序列分析

为明确菠萝叶斑病病原菌可可毛色二孢菌在海南省各市县的亲缘关系及遗传差异,从海南省的海口、澄迈、儋州、三亚、保亭等16个市县进行病样采集和病样分离,根据科赫氏法则鉴定,获得42株病原菌.观察形态特征,并基于多基因联合序列分析其遗传多样性.结果 表明,通过形态学鉴定和ITS与TUB2基因序列联合进化树分析发现,其中来自海口、澄迈、儋州、三亚、保亭等16个市县的16株代表病原菌均鉴定为可可毛色二孢菌(Lasiodiplodia theobromae),其分生孢子平均大小为(22.06～31.07) μm× (11.77～16.48) μm;通过ITS、TUB2、EF-1α、GAPDH、CHS-1和ACT基因拼接序列聚类分析,结果分为3个类群,海南岛的中部(儋州,昌江,白沙,五指山,万宁,琼海等地)聚为一个类群,中北部(屯昌,临高)聚为一个类群,西南部(东方,乐东,三亚等地)聚为一个类群.该结果说明来源于不同产地不同菠萝品种上的可可毛色二孢菌遗传多样性丰富,在海南省16个市县菠萝叶斑病菌中可可毛色二孢菌L.theobromae为优势种.     

烟草根黑腐病拮抗内生细菌的筛选及其抑菌作用

【目的】从烟草根、茎中分离获得对烟草根黑腐病菌(Thielaviopsis basicola)有较好控病作用的内生细菌。【方法】采用平板对峙培养,测定分离获得的306个内生细菌对烟草根黑腐病菌的抑制作用;通过菌株形态特征、生理生化特性及16S rDNA序列对菌株进行分类鉴定。【结果】筛选获得6个菌株对烟草根黑腐病菌有较强拮抗作用,室内测定其对病原菌的抑菌带宽达6.5 mm-11.0 mm,温室控病效果达11.9%-77.1%,其中来自茎部的内生细菌T295菌株对烟草根黑腐病的防效达77.1%;无菌滤液实验表明,拮抗内生细菌T295无菌滤液在实验浓度范围内对病菌菌丝生长、孢子萌发有较好地抑制作用。【结论】菌株T295对烟草根黑腐病具有较好的防治作用,经鉴定为枯草芽孢杆菌(Bacillussubtilis)。     

豌豆茎基腐病病原菌分离鉴定及其对杀菌剂的敏感性测定

豌豆(Pisum sativum)是我国重要的豆类经济作物, 病害对豌豆生产造成重大经济损失。通过形态学观察、分子鉴定以及致病性测定, 最终确定引起豌豆茎基腐病的3种病原菌分别为尖孢镰刀菌(Fusarium oxysporum)、芸苔链格孢菌(Alternaria brassicae)和格氏镰刀菌(F. grosmichelii), 优势菌株为尖孢镰刀菌, 分离率为53.6%。室内毒力测定结果表明, 5种供试杀菌剂对3种病原菌的菌丝生长均有抑制作用, 其中咯菌腈和戊唑醇的抑菌效果最好。研究结果为豌豆茎基腐病的防治提供了科学依据。     

可可毛色二孢致角膜溃疡病例分析

本文报告1例可可毛色二孢致角膜溃疡。患者男,54岁,右眼发红,疼痛加重3天。眼科检查见右眼球结膜混合充血,角膜全层灰白色浑浊,呈地图状,面不平,前房下方可见淡白色沉积,余眼内情况窥不清。取角膜刮取物标本进行真菌荧光染色镜检和培养,对培养的菌株进行形态学和分子生物学鉴定,用E-test法进行丝状真菌药敏试验。真菌荧光染色后,镜下可见有隔菌丝。培养14 d有分生孢子座产生,分生孢子位于分生孢子座里。对培养出的丝状真菌进行基因测序,测序后确定病原菌为可可毛色二孢(Lasiodiplodia theobromae,L.theobromae),临床诊断为可可毛色二孢引起的角膜溃疡。药敏试验结果显示,L.theobromae对两性霉素B和伏立康唑相对敏感。给予局部药物治疗,氟康唑滴眼液q2h滴右眼,同时使用氟康唑氯化钠注射液0.4 g qd静脉滴注。患者治疗5 d未见好转,要求出院。     

一种六妹羊肚菌的新型柄腐病害

近年来,四川等地种植的六妹羊肚菌先后爆发柄腐病害,造成严重经济损失。本研究对该病害发生情况进行了调查,从四川、河南、甘肃、贵州4个省收集的12份六妹羊肚菌柄腐病子实体,分离纯化得到37株真菌和3株细菌。根据柯赫氏法则,对所有分离纯化得到的疑似病原菌进行了回接试验,最终确定GJB-3菌株为柄腐病的病原菌。经ITS、RPB2和EF1α序列分析,结合菌落形态和显微特征鉴定柄腐病的病原菌为Fusarium nematophilum。本研究为后期羊肚菌生产病害防控提供了有效的基础数据。     

一株苹果树腐烂病病原菌的分离与初步鉴定

苹果树腐烂病已成为严重影响甘肃产区苹果产量和品质的重要病害之一,为确定其致病的致病菌,对采自甘肃省镇原县的苹果树腐烂病病枝,以组织分离和离体枝条接种的方法进行病原菌的分离和致病性测定。结果获得了一株苹果树腐烂病致病菌,通过培养特征、显微形态和rDNA-ITS序列分析综合鉴定及菌体回接实验,初步确定致病菌菌株P1为黑腐皮壳菌(Valsa mali)。     

多肉植物翡翠景天黑腐病病原菌

福建漳州是景天科Crassulaceae多肉植物翡翠景天Sedum morganianum主产地。近年来,该植物黑腐病发病严重,为鉴定其病原菌,从福建漳州3个翡翠景天种植基地采集典型病株并分离病原菌,基于形态学观察及rDNA-ITS、actin、EF-1α基因序列分析和致病性测定,界定该病原菌为山扁豆生棒孢Corynespora cassiicola。该菌引起多肉植物翡翠景天黑腐病为世界首次报道。     

邳州地区霉腐蒜头致病性真菌的分离鉴定

[目的]分离鉴定江苏邳州地区霉腐蒜头的致病真菌,为防控该地区蒜头腐败,延长蒜头贮藏期提供理论指导。[方法]对江苏邳州霉腐大蒜的腐败真菌采用点接法培养分离纯化,科赫氏法则和粘片法对蒜头霉腐微生物菌落形态、菌丝显微结构进行观察,并进行分子生物学鉴定。[结果]分离得到7株菌株,确定病原菌A为芽枝霉菌(Cladosporium cladosporioides),B为黑霉菌(Cladosporium cladosporioide),C为鲜绿青霉菌(Penicillium verrucosum),D为白腐菌(Trametes versicolor),E、G为芽枝状枝孢霉菌(Cladosporium cladosporioide),F为青霉菌(Penicillium chrysogenum),H为烟曲霉菌(Aspergillus funigatus)。[结论]导致江苏邳州地区大蒜霉腐的真菌主要是芽枝霉菌(Cladosporium cladosporioides)、黑霉菌(Cladosporium cladosporioide)、鲜绿青霉菌(Penicillium verrucosum)、白腐菌(Trametes versicolor)、芽枝状枝孢霉菌(Cladosporium cladosporioide)、青霉菌(Penicillium chrysogenum)、烟曲霉菌(Aspergillus funigatus)。     

凡纳滨对虾黑鳃病病原的分离鉴定及耐药性分析

旨在鉴定凡纳滨对虾(Litopenaeus vannamei)越冬亲虾出现黑鳃病的病原并对该病原进行耐药性分析。采用平板分离法从濒死的病虾病灶(鳃丝)分离到一株优势菌株,综合菌体的形态学鉴定以及真菌ITS-rDNA基因序列进行分析。结果显示,优势菌株与腐皮镰刀真菌(Fusarium solani)的序列同源性达99%以上,构建的系统发育树与腐皮镰刀真菌聚为一类,最终确定分离的优势菌株为腐皮镰刀真菌。进一步根据柯赫氏法则进行人工感染试验,证实其为病原菌且具有较强的致病性,病虾出现黑鳃,以5.0×105 CFU/mL浓度感染的对虾(25μL/尾)7 d致死率为53.33%。选取11种常见药物,采用琼脂稀释法和参照美国国家临床试验标准委员会(NCCLS)的M38-A2方案进行药物敏感试验,初步筛选后发现该菌株对克霉唑、益康唑、特比萘芬、制霉菌素、那他霉素、酮康唑等6种药物敏感,且益康唑的最小抑菌浓度(MIC)为1μg/mL,特比萘芬MIC为4μg/mL,对克霉唑、那他霉素的MIC为8μg/mL,对咪康唑、伊曲康唑的MIC为16μg/mL。本研究确定了分离到的优势菌株的致病性、耐药性和分类地位,为凡纳滨对虾越冬亲虾黑鳃病的防控提供了参考。     

一个新的体外快速鉴定十字花科黑腐病菌Ⅲ型效应物的报告质粒的构建

植物病原菌侵染寄主的过程就是病原菌和寄主植物相互作用的过程.在这个相互作用过程中,Ⅲ型分泌系统和Ⅲ效应物与病原菌致病密切相关.大部分革兰氏阴性植物病原菌通过Ⅲ型分泌系统定向的把效应物蛋白传递到宿主细胞,效应物蛋白进入植物体引起致病或过敏反应.本研究将百日咳杆菌的腺苷酸环化酶基因连接至含启动子的pLAFRJ载体上,从而构建出一个新的体外快速鉴定Ⅲ型效应物的报告质粒pJJA,并用已鉴定为Ⅲ型效应物基因的十字花科黑腐病菌XC1553的启动子和信号区验证该报告质粒,证明这个系统是可以工作的.该报告质粒为进一步精确筛选鉴定十字花科黑腐病菌Ⅲ型效应物提供了材料.     

Investigation of the mechanism of temperature sensitivity of the electroreceptors of ampullae of lorenzini

In experiments on Black Sea skates (Raja clavata), the potential of the receptor epithelium of the ampullae of Lorenzini and spike activity of single nerve fibers connected to them were investigated during electrical and temperature stimulation. Usually the potential within the canal was between 0 and –2 mV, and the input resistance of the ampulla 250–400 k. Heating of the region of the receptor epithelium was accompanied by a negative wave of potential, an increase in input resistance, and inhibition of spike activity. With worsening of the animal's condition the transepithelial potential became positive (up to +10 mV) but the input resistance of the ampulla during stimulation with a positive current was nonlinear in some cases: a regenerative spike of positive polarity appeared in the channel. During heating, the spike response was sometimes reversed in sign. It is suggested that fluctuations of the transepithelial potential and spike responses to temperature stimulation reflect changes in the potential difference on the basal membrane of the receptor cells, which is described by a relationship of the Nernst's or Goldman's equation type.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. I. M. Sechenov, Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Pacific Institute of Oceanology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Neirofiziologiya, Vol. 12, No. 1, pp. 67–74, January–February, 1980.     

Principles of organization and evolution of systems of regulation of functions

Evolution of living organisms is closely connected with evolution of structure of the system of regulations and its mechanisms. The functional ground of regulations is chemical signalization. As early as in unicellular organisms there is a set of signal mechanisms providing their life activity and orientation in space and time. Subsequent evolution of ways of chemical signalization followed the way of development of delivery pathways of chemical signal and development of mechanisms of its regulation. The mechanism of chemical regulation of the signal interaction is discussed by the example of the specialized system of transduction of signal from neuron to neuron, of effect of hormone on the epithelial cell and modulation of this effect. These mechanisms are considered as the most important ways of the fine and precise adaptation of chemical signalization underlying functioning of physiological systems and organs of the living organism