温度调控对番茄灰霉病菌侵染的影响

从群体的角度研究了番茄灰霉病菌对温度的适应性,结果表明灰霉病菌孢子的萌发适温在15～25℃,最适温度为20℃。15～25℃适宜菌丝生长、侵染与扩展,20℃为最适温度。30℃以上病害发展受到抑制。低温有利于病菌产孢,最适温度为15℃。变温研究表明,在一天中,随着30℃以上高温时间的增长,病菌(菌丝)的致病力呈下降趋势,6 h以上高温能够限制病害发展。     

温湿度调控对番茄灰霉病菌产生的细胞壁降解酶的影响

 番茄灰霉病菌在致病过程中能够产生4种细胞壁降解酶,以PMG酶活性最高,其次是β-葡萄糖苷酶和PG酶,Cx最少。灰霉病菌在不同温度下侵染番茄叶片时产生的致病酶活性不同,4种酶在20℃时表现了最高的活性,15℃次之,当温度达到25℃时,各种酶的活性都急剧下降,随着温度的再升高,酶活更低。随着湿度的增高,病菌产生的细胞壁降解酶的活性也增加,当相对湿度达到90%以上时,4种酶的活性也达到最高。温湿度对番茄灰霉病菌产生细胞壁降解酶的影响趋势,与其对发病的影响趋势是一致的。     

丙烷脒对番茄灰霉病菌生长发育的影响

利用电子显微技术研究了丙烷脒在活体植物上对番茄灰霉病菌Botrytis cinerea Pers.生长发育的影响。结果表明:丙烷脒对番茄灰霉病菌的生长发育有明显影响,但不同时期施药,表现出一定的差异性。扫描电镜观察发现,在先施药后接菌的情况下,番茄灰霉病菌产孢量显著下降,并且所产孢子表现出凹陷、变形等不良发育状况;在先接菌后施药的情况下,丙烷脒处理后不影响番茄灰霉病菌的产孢量,但所产孢子也表现出凹陷、变形等不良发育状况;透射电镜观察发现,在先施药后接菌的情况下,番茄灰霉病菌无法有效地侵入番茄表皮以下组织,病情得以有效控制;在先接菌后施药的情况下,药剂处理的番茄灰霉病菌可以侵入番茄表皮以下组织,但生长状况不良。不同时期丙烷脒处理后均能使番茄灰霉病菌的菌丝出现塌陷、生长点缢缩等不良生长现象;病菌菌丝细胞壁表现出不规则的加厚,尤以顶端加厚明显;线粒体异常增多,并出现基质型肿胀;病菌菌丝内细胞器液泡化,最终形成大的液泡;病菌细胞内含物外渗,出现质壁分离和空腔细胞;病菌细胞器泡囊化解体和细胞组织崩解,细胞趋于死亡等。研究表明,丙烷脒对番茄灰霉病菌的生长发育具有明显的影响,除具有保护性防病效果外,还表现出较强的治疗效果。     

番茄灰霉病菌对嘧霉胺的抗药性

2001年从辽宁省不同地区的保护地中采集番茄灰霉病果或病叶，经单孢分离共获得番茄灰霉病菌70株。采用菌丝生长速率法测定了其对嘧霉胺的敏感性。结果表明，番茄灰霉病菌已对嘧霉胺产生中等水平抗药性，抗性频率为20．0％。经室内药剂诱导获得了高抗菌株，抗性倍数最高达35．7倍。嘧霉胺与多菌灵及嘧霉胺与速克灵间不存在交互抗药性。野生抗性菌株具有较好的遗传稳定性，连续转接9次后抗药性无明显下降。不同菌株的菌丝生长速度、鲜重和渗透敏感性存在显著差异，但该差异与灰霉病菌对嘧霉胺的敏感性无相关性。抗性菌株与敏感菌株具有同样的致病能力。     

辣椒番茄灰霉病

辣椒番茄灰霉病黄绍岗（广西植保总站）辣椒番茄灰霉病是广西普遍发生的病害，造成死蔸和枯枝。南宁、梧州市郊的菜农反映，随着辣椒的连片种植，此病有加重的趋势。Ｉ症状识别辣椒番茄灰霉病可在茎杆、枝条、叶片上发生。苗期至成株期均可为害。但在辣檄、茄子上的症状及...     

北京地区番茄灰霉病菌对嘧霉胺的抗药性检测

为了检测北京地区番茄灰霉病菌对嘧霉胺的抗药性,指导生产上科学用药,从北京12个区、县采集番茄灰霉病样150份,分离纯化获得109个番茄灰霉病菌(Botrytis cinerea)的单孢菌株,采用菌丝生长速率法测定了番茄灰霉病菌对嘧霉胺(pyrimethanil)的抗药性。所测菌株中嘧霉胺抗性菌株出现的比例高达82.57%,且以高抗菌株为主,占78.89%,抗性水平最高的菌株EC50是最敏感菌株的5 096倍;不同区县番茄灰霉病菌对嘧霉胺的抗药性存在差异,门头沟区、密云县、延庆县、怀柔区和平谷区、大兴、通州和顺义8个区县的高抗菌株所占比例达66.67%～100%,海淀、朝阳和房山3个区未检测到高抗菌株。上述结果说明北京地区番茄灰霉病菌对嘧霉胺的抗药性非常普遍,且以高抗菌株为主,生产上应替换新型杀菌剂防治番茄灰霉病。     

8种杀菌剂对番茄灰霉病菌的毒力及田间番茄灰霉病菌对咯菌腈的敏感性

为了解决番茄灰霉病菌的抗性问题,筛选出理想的替代药剂,采用菌丝生长速率法测定了山东寿光和河北徐水两地番茄灰霉病菌对不同类型杀菌剂的敏感性。两地的番茄灰霉病菌对咯菌腈、氟啶胺均高度敏感,对其他不同作用方式的杀菌剂表现出不同的敏感性。用同样方法检测了不同地区的106株番茄灰霉菌对咯菌腈的敏感性,结果显示其EC50值分布在0.003 9～0.044 9μg/mL之间,平均EC50值为(0.014 2±0.008 1)μg/mL。咯菌腈可作为防治番茄灰霉病的候选药剂。     

喜树碱对番茄灰霉病菌的病理反应

以番茄灰霉病菌为供试菌种,采用电导率法、吸光度法和电镜分析法对经过喜树碱（CPT）处理的番茄灰霉病菌进行病理反应研究。试验结果表明经200 mg/L CPT溶液处理后,番茄灰霉病菌菌丝细胞膜的通透性增加了30.7%,细胞外蛋白质浓度提高了13.5%。番茄灰霉病菌经CPT溶液处理后,还原糖和可溶性蛋白的含量随着处理时间的增长先升高后降低最后趋于平缓,在0～1 h之间增长最快。CPT处理后的番茄灰霉病菌的菌丝畸形,出现膨大或缢缩,菌丝生长点缢缩,细胞中的空腔增多,线粒体增多且线粒体嵴变得模糊,细胞核有降解的现象。     

番茄灰霉病在果实上的侵染部位及防治新技术

 通过发病规律及人工接种研究,明确了番茄灰霉病菌Botrytis cinerea初侵染番茄果实的主要部位为残留的花瓣处及柱头处,随后扩展到果蒂部、脐部,最后蔓延到果实的其它部位。据此,在国内外首次提出了一种防治番茄果实灰霉病的新方法,在番茄用2,4-D蘸花后7~15 d(幼果直径10~20 mm)摘除残留的花瓣及柱头,防效达80%以上,对番茄单果重无影响。     

啶菌噁唑对番茄灰霉病菌的抑菌作用研究

采用生物测定方法研究了啶菌噁唑对番茄灰霉病菌Botrytis cinerea不同发育阶段的影响。结果表明:其对菌落扩展、芽管伸长、分生孢子产生和菌核形成均具有显著的抑制活性,其中啶菌噁唑对P-9菌株菌丝生长和芽管伸长的EC50值分别为0.193和0.154 μ g/mL,0.5 μ g/mL的啶菌噁唑对菌丝生长和芽管伸长的抑制率大于77%,对分生孢子和菌核萌发的抑制率分别低于10％和40%,表明药剂对分生孢子萌发无明显抑制作用。紫外吸收分析显示,啶菌 NFDA1 唑可破坏细胞的膜结构,促使菌体核酸和蛋白外渗。离体叶片毒力测定结果表明,120 μ g/mL的啶菌 NFDA1 唑可有效抑制番茄灰霉病病斑扩展,抑制率达83.74%。     

温湿度对枯草芽胞杆菌B36菌株可湿性粉剂防治番茄灰霉病效果的影响

本文研究了温湿度对枯草芽胞杆菌B36菌株可湿性粉剂防治番茄灰霉病效果的影响。结果表明：枯草芽胞杆菌B36菌株可湿性粉剂在相对湿度90%时,对番茄灰霉病保护和治疗效果最高,分别达82.9%和61.63%;在相对湿度100%时,对番茄灰霉病保护和治疗效果最差,分别达32.87%和31.63%。当相对湿度为90%,温度在30 ℃∥20 ℃条件下,对番茄灰霉病的保护和治疗效果分别为82.48%和63.01%;温度在25 ℃∥15 ℃条件下,对番茄灰霉病的保护和治疗效果分别为45.06%和23.85%。表明湿度及温度对枯草芽胞杆菌B36菌株可湿性粉剂防治番茄灰霉病的效果具有较大影响。     

番茄灰霉病菌拮抗放线菌的筛选、鉴定及其活性评价

从安徽省寿县农田土壤中分离筛选到1株对番茄灰霉病菌Botrytis cinerea有强拮抗作用的放线菌菌株HNU-1。根据菌体形态特征、培养特征、细胞壁组分、生理生化特性和16S rRNA基因序列分析,将该菌株鉴定为吸水链霉菌Streptomyces hygroscopicus。菌株HNU-1发酵滤液可抑制灰霉病菌菌丝生长和分生孢子萌发,且浓度越高,抑制能力越强;当发酵滤液稀释6.67倍时则完全抑制灰霉病菌菌丝生长和分生孢子萌发。盆栽试验结果表明,菌株HNU-1发酵滤液6.67倍稀释液对番茄灰霉病的预防与治疗效果分别为87.8%和77.9%,均显著高于50%多菌灵可湿性粉剂500倍稀释液。     

河南省番茄灰霉病菌对3种杀菌剂的抗药性检测

为了明确河南省番茄灰霉病菌对苯并咪唑类杀菌剂多菌灵、二甲酰亚胺类杀菌剂腐霉利和氨基甲酸酯类杀菌剂乙霉威的抗药性状况,2013年从河南省不同保护地中采集番茄灰霉病病果或病叶,经单孢分离共获得番茄灰霉病菌菌株139株。采用最低抑制浓度法（MIC）测定了其对多菌灵、腐霉利和乙霉威的抗药性。结果显示：番茄灰霉病菌对多菌灵、腐霉利和乙霉威产生抗性菌株的频率分别为81. 29%、80.58%和93.53%; 所测菌株对3类杀菌剂的抗性类型有BenRDicSNPCS、BenRDicRNPCS、BenRDicSNPCR、BenSDicRNPCR、BenSDicSNPCR和BenRDicRNPCR 6种,所占比例分别为2. 88%、3.60%、3.60%、5.04%、13.67%和71. 22%。表明河南省番茄灰霉病菌已对多菌灵、腐霉利和乙霉威产生抗药性,迫切需要筛选新的杀菌剂防治番茄灰霉病。     

4种杀菌剂及其复配剂对番茄灰霉病菌的毒力

采用菌丝生长速率法测定了咯菌腈、氟啶胺、啶酰菌胺和苯醚甲环唑4种杀菌剂及其两元复配剂对番茄灰霉病菌的毒力。结果显示,咯菌腈、氟啶胺、啶酰菌胺和苯醚甲环唑对番茄灰霉病菌的有效抑制中浓度(EC50)分别为:0.018 0、0.018 1、1.896 8和2.087 4μg/mL。复配剂啶酰菌胺∶苯醚甲环唑1∶5、1∶3和1∶1,咯菌腈∶苯醚甲环唑1∶5增效作用最明显;复配剂咯菌腈∶苯醚甲环唑1∶3,咯菌腈∶氟啶胺1∶3,啶酰菌胺∶咯菌腈5∶1,啶酰菌胺∶苯醚甲环唑3∶1具有增效作用,SR值范围为1.5~4.05,其中以复配剂啶酰菌胺∶苯醚甲环唑1∶5增效作用最好,其SR值为4.05;其余不同配比的各组合复配剂具有相加作用,其SR值范围为0.5~1.46。表明咯菌腈、氟啶胺、啶酰菌胺和苯醚甲环唑4种不同作用机制的杀菌剂可以交替或复配使用,以阻止或延缓灰霉病菌抗药性的进一步加剧,为灰霉病的综合防控和抗药性治理提供理论依据。     

Structure and Expression In planta of Botrytis cinerea Ubiquitin Genes

To identify genes of the necrotrophic pathogenic fungus Botrytis cinerea that are expressed during infection of tomato leaves, a differential screening of a genomic library with radioactively labelled cDNA was performed. This resulted in the identification of a B. cinerea gene, denominated Bcubi4, which encodes a precursor protein consisting of four identical head-to-tail repeats of a 76aa ubiquitin unit. Subsequently a gene denominated Bcubi1CEP79, encoding a single ubiquitin unit joined to a Carboxyl Extension Protein of 79 amino acids, was isolated. The expression of the two ubiquitin genes was studied during pathogenesis of B. cinerea on tomato. Bcubi1CEP79, but not Bcubi4, mRNA was transiently induced at 16h after inoculation. The increased expression of the Bcubi1CEP79 gene at this stage of pathogenesis might be required for enhanced ribosomal biogenesis.     

Resistance profiles of Botrytis cinerea populations to several fungicide classes on greenhouse tomato and strawberry in Lebanon

Tomato and strawberry are the most important protected crops in Lebanon and are seriously affected by grey mould disease, caused by Botrytis cinerea. In the present study, the fungicide sensitivity assays revealed medium to high frequencies of B. cinerea isolates resistant to benzimidazoles, dicarboximides, and anilinopyrimidines on tomato and strawberry. Fludioxonil- and boscalid-resistant mutants were uncommonly found at generally low frequency on both crops. Resistance to fenhexamid was detected in only one site on tomato but in most sites on strawberry with high frequencies, and the occurrence of resistance to QoI fungicides was ascertained on both crops. The majority of the tested isolates (>90%) exhibited multiple fungicide resistance, and isolates resistant to the seven antibotrydial fungicide classes were detected on strawberry in three locations. A high level of resistance was shown by B. cinerea mutants resistant to boscalid, fenhexamid, and QoI fungicides, while two levels of moderate and high resistance to anilinopyrimidines were identified. Genetic analysis revealed point mutations in the target genes commonly associated with resistance in B. cinerea isolates, with all mutants resistant to dicarboximides, fenhexamid, boscalid, and QoI fungicides carrying single-nucleotide polymorphims in BcOS1 (I365S/N, Q369P, and N373S), Erg27 (F412V/I), SdhB (H272R/Y), and cytb (G143A) genes, respectively. The general incorrect use of fungicides has caused the development and spread of fungicide resistance as a widespread phenomenon on protected tomato and strawberry in Lebanon. The implementation of appropriate antiresistance strategies is highly recommended.     

Fungal and plant gene expression during synchronized infection of tomato leaves by Botrytis cinerea

An inoculation procedure was developed to obtain efficient and synchronous infection on detached tomato leaves by Botrytis cinerea. In spray-inoculated leaves incubated at 20 °C, the infection process consisted of three phases: the formation of primary necrotic lesions (until 20 hpi), a quiescent phase (20-72 hpi), and the expansion of a proportion of the primary lesions (from 72 hpi onwards), resulting in full tissue maceration. At 4 °C, the infection progressed slowly but steadily without inducing necrotic responses in the host. The actin and -tubulin genes of B. cinerea were cloned, characterized and used as probes on blots containing RNAs from leaves at various stages of the infection. The genes displayed a similar expression pattern throughout the infection and the hybridization signal reflected the amount of fungal biomass. The actin mRNA accumulated to higher levels than the -tubulin mRNA. Tomato PR protein mRNAs (chitinase, -1,3-glucanase and PR-1) were induced during the infection, albeit with different kinetics and to different levels. At 20 °C, -1,3-glucanase and PR-1 mRNAs were induced more rapidly than chitinase mRNAs. At 4 °C, mRNAs encoding extracellular -1,3-glucanase and intracellular, as well as extracellular chitinase were hardly induced.     

生防细菌FD6的鉴定及其对番茄灰霉病菌的作用机制

拮抗细菌FD6分离自福建闽侯青口青菜根围土壤,采用凹玻片法和离体叶片接种法测定菌株FD6的抑菌能力,经16S rDNA序列比对和相关生理生化性状分析,对生防细菌FD6进行了鉴定,并通过PCR扩增、薄层层析、薄层色谱生物自显影等探讨FD6产生抗生素的种类及其抑菌效果。结果表明,FD6的细菌悬浮液可显著抑制灰霉病菌分生孢子萌发,抑制率达99%,FD6培养滤液的抑制率仅为31%;细菌悬浮液对番茄灰霉病防效达59.7%。FD6的16S rDNA序列与假单胞菌属Pseudomonas的相似性达99%,系统进化树显示与荧光假单胞菌P.fluorescens遗传距离最近,结合生理生化表型特征将FD6菌株鉴定为荧光假单胞菌P.fluorescens。菌株FD6可产生硝吡咯菌素、2,4-二乙酰基间苯三酚、藤黄绿脓菌素、嗜铁素、氢氰酸和蛋白酶等抗菌物质,不产生吩嗪-1-羧酸,其中,硝吡咯菌素可直接抑制番茄灰霉病菌孢子萌发和菌丝的生长。