野生番茄抗叶霉病生理指标的研究

欲获野生番茄抗叶霉病生理指标的重要数据资料 ,揭示其抗病机理。以多毛番茄、秘鲁番茄、小花番茄、多腺番茄醋栗番茄 5个野生番茄和 L 4 0 2栽培番茄为试材 ,设置接种处理和喷水作为对照。它们在接种叶霉菌生理小种1.2 .3后 ,其叶片的过氧化物酶 (POD)、多酚氧化酶 (PPO)、相对电导率、以及叶片木质素的变化情况。结果表明 ,野生番茄叶片中 POD、PPO活性、相对电导率和叶片木质素含量在接种后均有不同程度的增加基本上与抗病呈正相关 ,但各指标变化幅度和时间依各野生番茄又略有不同     

黄瓜黑星病菌核糖体基因ITS区段的克隆及序列分析

为了探讨枝孢霉属的系统发育情况,采用真菌核糖体基因转录间隔区域(ITS)通用引物,PCR扩增3株来自不同地方的黄瓜黑星病菌核糖体基因的ITS序列,并对PCR产物进行测序和序列分析。结果表明:3株黄瓜黑星病菌之间同源性为100%,ITS全长463bp,其中ITS1长154bp,5.8S rDNA长159bp,ITS2长150bp,各碱基的个数分别为G 119个、C 118个、A 120个、T 106个,GC含量为51.2%。利用MEGA4软件中的NJ法和ME法,对3个样品序列以及GenBank中登陆的枝孢霉属其他25个种构建ITS聚类分析树状图,NJ法和ME法构建的结果基本相同,枝孢霉属可以分为5个聚类组,所测的3个样品和Cladosporium cucumerinum在一个聚类组中。     

郑州地区3种冷季型草坪草根部入侵真菌鉴定

研究不同草坪草根部入侵真菌的种类对草坪病害鉴定与防治具有重要意义。本试验以河南省郑州市内8个公共草坪上的3种冷季型草坪草高羊茅(Festuca arundinacea),草地早熟禾(Poa pratensis)和多年生黑麦草(Lolium perenne)为研究材料,于2013年春季,在8个混播草坪上采用"Z"字形法随机进行根部取样,每种草在各采样地内分别取12株根样,并在实验室内分离鉴定其根部入侵真菌种类。结果表明:从288株根样中共分离到13种真菌,其中6种真菌为3种草根部共同的入侵真菌,包括:细交链孢(Alternaria alternata)、尖孢镰孢(Fusarium oxysporum)、柱孢(Cylindrocarpon destructuns)、枝孢(Cladosporium herbarum)、多隔镰孢(F.decemcellulare)、德氏霉(Drechslera sp.)。郑州地区冷季型草坪草根部入侵的主要病原真菌是细交链孢、尖孢镰孢和枝孢,不同地点和草种根部主要的入侵真菌种类有明显的不同,根部带菌率最高的是多年生黑麦草。     

Suppression of cucurbit scab on cucumber leaves by photodynamic dyes

The goal of this study was to test the ability of the photodynamic dyes bengal rose, toluidine blue and methylene blue to protect systemically cucumber plants from cucurbit scab. At the stage of one true leaf, water or aqueous solutions of the dyes were applied to the leaf as droplets. When the second leaf appeared and was fully developed, it was inoculated with a spore suspension of Cladosporium cucumerinum. It was found that all dyes (at 0.5-200 μM) significantly suppressed symptoms of the disease. The effect was preceded by development of local damage of the treated leaf. The degree of the damage as well as the disease suppression increased with dye concentration. Both indices were smaller if the plants were kept in darkness for the first day after the treatment. It is suggested that reactive oxygen photogenerated by dyes caused a local cell death, which induced resistance in distant leaves. The dyes tested, or their derivatives, may offer a base for novel disease resistance inducers.     

番茄叶霉病研究进展

番茄叶霉病是威胁保护地番茄生产的一种严重病害,为世界病害,可直接导致番茄减产,并严重影响番茄品质。根据国内外关于番茄叶霉病的研究情况,综述了番茄叶霉病的发病症状;病原菌的生物学特性,包括病菌的形态特征以及适宜菌丝和孢子的生长温度(20￣25℃)以及湿度(85%以上)等条件;病害的发生条件和流行规律;不同地区病菌生理小种的分化情况;生产上应选用毛粉802、双抗2号等抗病品种;番茄与病菌之间的作用机制;番茄Cf及ECP等抗病基因的克隆、结构和功能及病害防治等方面的研究情况。     

番茄抗叶霉病基因Cf12 的分子标记筛选及种质资源鉴定

 以番茄抗叶霉病的品种05HN36为母本,以感病品种051355为父本配置杂交组合,以亲本及其F₂分离群体为研究材料,采用AFLP技术筛选与抗叶霉病基因Cf12连锁的分子标记。通过对545对引物进行筛选,获得了6个连锁的AFLP标记：E86M51-C、E46M50、E95M59-D、E35M81、E78M36-C和E47M50-C,连锁遗传距离分别为5.1、8.9、9.1、9.2、10.2和10.8 cM。将E86M51-C转化为SCAR标记并应用于种质资源筛选,获得了16份含有该标记的番茄材料,为抗叶霉病育种提供材料基础。     

中国枝孢属研究Ⅻ

 报道枝孢属 Cladosporium Link ex Fries 4个新记录种:马丁枝孢 C. martianoffianum Thum,兰科枝孢 C. orchidis E.A.&;M.B.Elis,狭孢枝孢 C. stenosporum Berkeley&;Curtis和黑星状枝孢 C. venturicides Saccardo;附有它们的形态特征和显微结构图.研究标本存云南农业大学植病所真菌标本室(MHYAU).     

Summer Variation in the Concentration of Steroidal Sapogenins in and the Degree of Fungal Infection on Narthecium ossifragum plants from Møre og Romsdal County,Norway

Thirty-nine leaf samples ofNarthecium ossifragum collected from eight sites in More og Romsdal County, Norway, during June–September 1997 and 41 leaf samples collected at five sites in the same county during June–August 1998 were analysed for the concentrations of steroidal sapogenins using GC-MS. The 1998 samples were also examined for fungal elements (conidia and hyphae) after incubation in a moist chamber for 10–14 days. The highest 1997 and 1998 leaf sapogenin concentrations (4881 and 7115 mg/kg dry matter, respectively) were 13–14 times greater than the lowest sapogenin concentrations found (344 and 531 mg/kg dry matter, respectively). The results did not reveal systematic differences in sapogenin concentrations between the two seasons, or between samples harvested early or late in the same seasons, or between sapogenin concentrations in plants harvested at different sites.Cladosporium magnusianum was the predominant fungus found in the samples. The degree of fungal infection on the samples was in generally low, but the number ofC. magnusianum colonies in the moist chamber preparations and fungal elements (conidia and hyphae) in leaf washings and on leaves tended to increase with time. Factor analysis and multiple regression analysis performed on the chemical and fungal results suggest that sporulation may have occurred in the fungi in response to increase in sapogenin concentrations.     

瓜枝孢弱毒菌株基因组分析

经高温筛选到具有弱致病性的瓜枝孢菌株2R、3R。经稳定遗传特性试验表明,菌株2R经15代繁殖后弱致病性仍然得到稳定遗传。采用RAPD和AFLP技术在全基因组水平分析了高温诱导产生的瓜枝孢弱毒菌株的变化。结果表明AFLP技术可以有效地揭示弱毒菌株的DNA的变异,瓜枝孢经50℃高温处理后基因组发生了显著的变化。AFLP图谱分为三种：一种是弱毒菌株和野生型菌株的扩增谱带基本相同;另一种是弱毒菌株产生的谱带一部分与野生型菌株相同,同时出现新的扩增片段;第三种情况是弱毒菌株有新的DNA片段产生,但是与野生型菌株相同的大部分主带消失。256个AFLP引物组合在扩增2R/2Q和3R/3Q时（瓜枝孢弱毒菌株2R和3R,野生型菌株2Q和3Q）,分别在2910和2216个位点上有DNA片段产生,2R与2Q以及3R与3Q的遗传相似性分别为24.81%和43.68%。