几种杀菌剂对茶轮斑病菌的室内毒力及田间药效

为了筛选防治茶轮斑病的化学药剂,采用菌落直径法测定了茶轮斑病菌对7种杀菌剂的敏感性,并对茶轮斑病菌高度敏感药剂进行田间药效试验。结果表明：轮斑病菌对阿米西达、世高、丙环唑、百菌清和苯菌灵高度敏感,其抑制中浓度（EC50）在0．0947～3．0630μg/mL;甲基托布津和多菌灵的 EC50分别为6．9649μg/mL 和7．0405μg/mL,表现为中度敏感（EC50＝5～20μg/mL）;田间药效以25％阿米西达SC 150 g/hm2的防效最高,达86．96％;其次为10％世高 WG 125 g/hm2、25％丙环唑 EC 112．5 g/hm2和75％百菌清WP 125 g/hm2,防效分别为81．16％、74．79％和72．38％;50％苯菌灵WP 325 g/hm2防效最低,为62．21％。     

蓝莓叶斑病病原菌鉴定及其生物学特性

为明确山东省蓝莓叶斑病病原菌的种类及其生物学特性,采用组织分离法获得菌株B1,通过形态学特征并结合r DNA-ITS序列分析对该菌株B1进行鉴定,以离体和活体叶片接种法测定菌株B1的致病性,并对其生物学特性进行研究。结果表明,菌株B1菌落呈白色绒毛状,背面淡黄色,分生孢子纺锤形,5个细胞,中间3个细胞为褐色,具有2～4根顶端附属丝;菌株B1的ITS序列与GenBank中棒状拟盘多毛孢Pestalotiopsis clavispora的相似性达99%以上,结合形态特征与rDNAITS序列分析将病原菌鉴定为棒状拟盘多毛孢,GenBank登录号为MG009201。菌株B1接种蓝莓叶片后产生褐色病斑,后期密生黑色分生孢子盘,与蓝莓田间自然发病症状一致。该菌株在5～35℃、pH 5～11范围内均可生长,最适温度范围为25～30℃,最适pH范围为5～9;但仅在25～30℃时产生分生孢子,最适产孢温度为25℃;光照条件对菌丝生长无明显影响,但连续黑暗有利于产孢;以葡萄糖为碳源时利用率最高,对乳糖利用效果最差;最适氮源为硝酸钠、硫酸铵和蛋白胨,几乎不能利用尿素。     

枇杷拟盘多毛孢生物学特性研究

从不同培养基、温度、pH值、光周期及湿度对枇杷拟盘多毛孢菌(Pestalotiopsis eriobotryfolia)生长的影响进行系统研究,为由该菌引起的病害防治提供理论依据。结果表明该菌菌落生长的适宜温度范围是12~30℃,最适温度26℃;在7种培养基中,PSA和含维生素的培养基有利于该菌落生长和产孢;菌落扩展和菌丝干重增加的最适pH是7,适合孢子萌发的pH是4;全光照有利于菌落生长和孢子萌发;分生孢子在饱和湿度中萌发率最高,24 h后孢子萌发率为44.59%;菌丝块致死温度为56℃、15 min,分生孢子致死温度为54℃、15min。     

中国拟盘多毛孢属的新组合种(Ⅲ)

本文为中国拟盘多毛孢属新组合种（Ⅰ）、（Ⅱ）的续篇，报道１１个不同的新组合种。这１１个新组合种是：３６．寄生在柑桔和黄皮树叶部的柑桔拟盘多毛孢（Ｐｅｓｔａｌｏｔｉｏｐｓｉｓｃｉｔｒｉ（Ｍｕｎｄｋ＆Ｋｈｅｓｗａｌａ）Ｙ．Ｘ．Ｃｈｅｎｃｏｍｂ．ｎｏｖ）；３７．寄生在忍冬科荚艹迷属植物的叶部的双纤毛拟盘多毛孢（Ｐｅｓｔａｌｏｔｉｏｐｓｉｓｂｉｃｉｌｉａ（Ｄｅａｒｎ＆Ｂｉｓｂｙ）Ｙ．Ｘ．Ｃｈｅｎｃｏｍｂ．ｍｏｖ．）；３８．寄生在腰果树叶部的异角状的拟盘多毛孢（Ｐｅｓｔａｌｏｔｉｏｐｓｉｓｈｅｔｅｒｏｃｏｒｎｉｓ（Ｇｕｂａ）Ｙ．Ｘ．Ｃｈｅｎｃｏｍｂ．ｎｏｖ．）；３９．寄生在月桂的叶部的孢子器型拟盘多毛孢（Ｐｅｓｔａｌｏｔｉｏｐｓｉｓｐｙｃｎｏｉｄｅｓ（Ａｌｍ．＆Ｃａｍａｒａ）Ｙ．Ｘ．Ｃｈｅｎｃｏｍｂ．ｎｏｖ．）；４０．寄生在杜鹃花科的白珠树叶部的白珠树拟盘多毛孢（ＰｅｓｔａｌｏｔｉｏｐｓｉｓｇａｕｔｈｅｒｉａｅＤｅａｒｎ＆Ｈｏｕｓｅ）Ｙ．Ｘ．Ｃｈｅｎｃｏｍｂ．ｎｏｖ．）；４１．寄生在雀梅藤和鼠李叶部的鼠李拟盘多毛孢（Ｐｅｓｔａｌｏｔｉｏｐｓｉｓｒｈａｍａｎｉ（Ｃｅｌｏｔｉ）Ｙ．Ｘ．Ｃｈｅｎｃｏｍｂ．ｎｏｖ．）；４２．     

云南葡萄病害研究初报

 本文报道云南22种葡萄真菌性病害,国内未报道的病害有9种,其中5种有描述和附图,即葡萄小褐斑病Anaphysmene sp,叶斑病Discosia sp,黑星病Fusicladium viticis,枝枯病Massamia phomeioides,大叶斑病Pestalotiopsis sp,后3种进行单孢分离接种;另4种为省内未报道的病害,即葡萄灰霉病Botrytis cinerea,黑点病Septoria sp,黑斑病Alternaria viticola,叶枯病Monochaetia uniseta,亦进行描述并附图。     

猕猴桃褐腐病生防菌株GMH31发酵条件的优化

利用从药用植物牡蒿(Artemisia japonica)中分离筛选出的1株猕猴桃褐腐病生防菌株GMH31,采用含毒介质平板法进行抑菌试验,通过单因子试验和正交试验,对该菌株的最适发酵培养基成分(包括碳源、氮源、无机盐离子、微量元素)及发酵条件(包括发酵时间、温度、pH、转数、装液量、接种量)进行了优化。结果显示:尤韦可拟盘多毛孢菌株GMH31培养基组分最佳配比为麦芽糖35 g/L、氯化铵12 g/L、K_2HPO_40.1 g/L、甘氨酸0.015 g/L,最佳发酵条件为培养时间14 d、培养温度26℃、初始pH 6.0、摇床转速120 r/min、250 m L装液量100 m L、接菌量为装液量的6%。在最佳发酵培养基和培养条件下,GMH31菌株发酵滤液对猕猴桃褐腐病菌的抑制率提高了16.45%。     

Characteristics of Pestalotiopsis Associated with Hardy Ornamental Plants in the UK

Pestalotiopsis isolates obtained from the foliage, stem-base and roots of hardy ornamentals grown on commercial nurseries in the UK were identified and characterised according to pathogenicity and colony morphology. All 18 isolates were identified as Pestalotiopsis sydowiana on the basis of conidia morphology, and confirmation of identification was made by experts at CABI Bioscience. Isolates were pathogenic on the host from which originally isolated. Typical symptoms included foliar browning of foliage and stems, and the presence of black or greenish-black acervuli on diseased tissue. Isolates were not host specific and infected other species of hardy ornamentals. Three colony types on potato dextrose agar were distinguished according to colour and production of acervuli by individual isolates.Three selected isolates of P. sydowiana were characterised by examining the effects of growth media, temperature, pH, and water potential on hyphal extension. Isolates grew well on commonly used growth media, including PDA, Sabouraud dextrose agar (SDA), V8 juice agar (V8), malt extract agar (MEA) and Czapek Dox agar (CDA). The optimum temperature for growth on PDA was in the range 20–25°C, with little or no growth occurring below 5°C or above 30°C. Hyphal extension occurred over a pH range between 2.6–8.6, with optimum values occurring at pH 5.5. In general, decreases in osmotic and matric potential caused a reduction in growth. Hyphal extension on media adjusted osmotically as NaCl ceased between –9.9 and –10.5MPa. Isolates were more tolerant of osmotic than matric potential, with no growth occurring at –6.5MPa on media adjusted with polyethylene glycol.     

石楠拟盘多毛孢致病毒素的初步分离纯化

为了获得引起草莓根腐病的石楠拟盘多毛孢(Pestalotiopsis photiniae)产生的致病毒素组分,利用中压硅胶柱层析、高效液相C-18制备柱层析和sephadex LH-20层析对粗毒素进行了分离纯化,以离体叶盘针刺法检测分离所得组分的致病活性。结果显示:经中压硅胶柱层析和高效制备液相色谱得到了FrⅢ1和FrⅢ2两个组分,其中FrⅢ1有较强活性;用sephadex LH-20对FrⅢ1进一步纯化后又得到了两组活性组分FrⅣ1-2和FrⅣ3-4,其中组分FrⅣ3-4的活性明显强于组分FrⅣ1-2;HPLC分析发现这两组组分又分别含有2个和5个组分,7个组分均在C-18柱层析过程中出峰时间较早,说明该毒素的极性较大。     

滇重楼稻曲拟盘多毛孢叶斑病病原鉴定及其生物学特性测定

为明确滇重楼Paris polyphylla var. yunnanensis (Franch) Hand.-Mazz一种新的叶斑病病原菌, 以云南省丽江市玉龙纳西族自治县中药材种植基地内发现的一种新真菌性病害为供试研究材料, 经单孢分离培养?形态特征观察?致病性测定?多基因系统发育分析(ITS?tub2?tef1)和生物学特性测定, 对病原物进行分类鉴定?研究结果表明, 病原物CL107形态符合Pestalotiopsis sp.种属典型特征; 菌株CL107-ITS(accession no. MK156295)?CL107-BT(accession no. MN015425)?CL107-EF1(accession no. MN022941)与参比标准菌株P.oryzae CBS 353.69同源性分别为100.00%?100.00%?98.92%, 可将稻曲拟盘多毛孢P.oryzae确定为滇重楼叶斑病病原物?生物学特性研究表明, PDA培养基?pH 8.0?28℃?全黑暗条件有利于菌株CL107菌丝生长和分生孢子形成, 以葡萄糖为碳源有利于纯化菌株菌丝生长和产孢; 以酵母提取物为氮源有利于纯化菌株菌丝生长, 以牛肉膏为氮源有利于纯化菌株产孢?本研究首次报道稻曲拟盘多毛孢P. oryzae可侵染滇重楼植株, 引起真菌性叶斑病, 明确影响病害发生的环境因子, 为该叶斑病的诊断与防治提供科学依据和理论指导?