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1.
 近些年链格孢属真菌的分类有了长足的进展,但柑橘褐斑病和黑腐病的病原却还是存在着一些争议。本研究从中国柑橘果实上收集了49株黑腐病菌菌株,并选取了8株从柑橘叶片上分离的具代表性的褐斑病菌菌株,基于Alta1 、endoPG、LSU、OPA10-2、OPAl-3和OPA2-1 等6个基因位点串联序列构建系统发育树。结果表明,柑橘黑腐病和褐斑病都可由不止一种链格孢菌引起,均以Alternaria alternata为主。两种病害的病原菌之间不能通过该系统发育树区分,但在致病性上存在差异,且能通过扩增ACT毒素合成基因进行区分。为了使两种病害的病原更加方便阐述,作者建议以它们的主要类群对其进行命名,柑橘褐斑病病原学名还是遵循前人的称呼,为the tangerine pathotype of A. alternata,即链格孢菌橘致病型,而柑橘黑腐病病原应为A. alternata,即链格孢菌。  相似文献   

2.
为明确在福建省南平市的橘柚和三明市的温州蜜橘上发现的疑似柑橘褐斑病的病原菌种类,采用组织分离法获得纯化菌株,通过回接法验证菌株的致病性,利用形态学特征对病原菌进行初步鉴定,并采用最大似然法以多聚半乳糖醛酸酶基因endoPG为靶标对本研究以及国内外已报道的链格孢菌株构建系统发育树,分析其遗传多样性。结果表明,从病组织中共分离获得26株纯培养菌株,经形态学鉴定均为链格孢菌Alternaria spp.。利用分生孢子液接种橘柚离体嫩叶发现,有22株菌株能侵染橘柚叶片并产生与田间相似的褐斑病症状,确认该病害为链格孢引起的柑橘褐斑病。系统发育树分析结果显示,分离所得的26株菌株均聚在已报道的4个柑橘链格孢进化分支Clade1~Clade4中,其中21株菌株聚在国内特有的分支Clade4中,有3株菌株和1株菌株分别聚在国内外兼有的分支Clade3和Clade1中,1株菌株聚在国外特有的分支Clade2中,表明在福建省采集的这些柑橘褐斑病菌均为链格孢菌,且遗传多样性较丰富。  相似文献   

3.
由交链格孢菌橘致病型(Alternaria alternata tangerine pathotype)引起的柑橘链格孢褐斑病(Alternaria brown spot,ABS)是柑橘上的主要病害,目前主要采用杀菌剂防治。本研究以采自中国各柑橘链格孢褐斑病发生区的54个交链格孢菌橘致病型菌株为供试群体,采用刃天青微平板法测定了病原菌孢子萌发和菌丝生长对戊唑醇和苯醚甲环唑的敏感性。结果表明:刃天青微平板法最佳体系中的培养基为完全培养基(CM),刃天青终浓度为40 μmol/L,孢子浓度为105个/mL。戊唑醇和苯醚甲环唑的有效抑制中浓度(EC50)范围分别为0.304~0.885 μg/mL和0.367~0.873 μg/mL,平均值分别为0.562和0.609 μg/mL。正态分布检测结果显示:这2种药剂抑制交链格孢菌橘致病型群体的EC50值均符合正态分布,因此认为所得EC50值可作为病原菌对戊唑醇和苯醚甲环唑的敏感性基线。本研究结果可为田间防治褐斑病和监测交链格孢菌对戊唑醇和苯醚甲环唑的抗药性奠定基础。  相似文献   

4.
文章描述玉米链格孢菌叶枯病田间为害症状、病原茵的培养与传播,分析了宾川县玉米链格孢菌叶枯病发生条件和提出了综合防治技术措施.并应用于玉米田间生产,取得了显著的效果.  相似文献   

5.
红橘褐斑病病原为链格孢菌Alternarin alternatar (Fr.)Keissle。既可寄生,又可腐生,在很广的温湿度条件下都能生存,繁殖速度快。潜伏时间短,发生时间长,为害重。防治困难,甚至有人认为不可防治。该病自2007年暴发以来,应用常年使用的多菌灵、三唑酮、丙环唑、甲基硫菌灵等唑类杀菌剂防治效果很不理想。笔者2011年选用市场上易购的高效、低毒、环保非唑类杀菌剂百菌清、腐霉利、嘧霉胺、多抗.锰锌、福美双等药剂对红橘褐斑病进行了田间防治试验。  相似文献   

6.
2007年以来红橘褐斑病Alternaria alternata(Fr.)Keissler在重庆万州暴发、蔓延,为害程度逐年加重,发病面积不断扩大。该病在当地主要为害红橘(品种大红袍),椪柑、伊予柑(橘和柚的杂交种)也可发病,但与严重发病的红橘同在一个橘园的甜橙并不受害。该病在红橘春梢期、幼果期和果实膨  相似文献   

7.
王艳  陈秀蓉  杨成德 《植物保护》2013,39(4):116-118
对2004年以来甘肃省百合科、苋科、木犀科、大戟科、桔梗科药用植物链格孢属引起的病害进行了鉴定,结果如下:芍药叶斑病病原为细链格孢[Alternaria alternata (Fr.:Fr.)Keissler],青葙叶斑病病原为青葙链格孢[A.ce-losiae (Tassi)O.Sǎvul],连翘灰斑病病原为A.forsythiae Harter,引起连翘灰斑病、甘遂褐斑病病原为甘遂链格孢(A.kansuiae T.Y.Zhang&.Z.Zhang),沙参黑斑病的病原为茄链格孢[A.solani(Ellis et Martin)Sorauer].  相似文献   

8.
<正>葡萄褐斑病又称叶斑病,是葡萄生产上的一种常见病害,根据病斑大小和病原物不同分为大褐斑病和小褐斑病。我国各地报道的葡萄褐斑病主要以大褐斑病为主,其病原为葡萄拟尾孢菌Pseudocercospora vitis(梁春浩等,2009),主要为害葡萄叶片,可造成叶片早期脱落,光合作用下降。目前该病的鉴别主要通过技术人员实地观察,主观性强,传统的病原分离培养和鉴定虽然结果准确,但需较  相似文献   

9.
青海省樱桃叶斑病病原菌的分离与鉴定   总被引:2,自引:0,他引:2  
为明确引起青海省樱桃叶斑病病原菌的种类,本研究从西宁市城北区、海东市乐都区和贵德县的樱桃上采集有叶斑症状的叶片,采用组织分离法分离出病原菌,通过观察病原菌的形态特征,结合rDNA-ITS、EF-1α和Alt a 1基因序列分析对病原菌的种类进行了鉴定,并用柯赫氏法则进行验证。结果表明,共获得279株病原菌菌株,分属链格孢Alternaria alternata、细极链格孢A.tenuissima和刺盘孢属Colletotrichum spp.,分离频率分别为84.95%、5.02%和10.03%。采用柯赫氏法则进行离体叶片致病性测定,接种叶片100%发病,说明引起青海省樱桃叶斑病的病原菌为链格孢、细极链格孢和刺盘孢属真菌,且链格孢为主要病原菌。该研究结果可为青海省樱桃叶斑病的综合防治提供理论依据。  相似文献   

10.
外来杂草在海南的危害及病害调查   总被引:2,自引:0,他引:2  
对海南13种外来杂草展开调查,其中分布广泛、危害最为严重的是飞机草和假臭草。在9种外来杂草上共分离获得17种真菌,分别是侵染假臭草的链隔孢(Alternaria sp.)、镰刀菌(Fusarium sp.),侵染飞机草的飞机草泽兰尾孢(Cerospora eupatorii Peck.)、炭疽菌(Colletotrichum sp.)和链格孢(Alternaria sp.),侵染蟛蜞菊的链隔孢(Alternaria sp.)和炭疽菌(Colletotrichum sp.),侵染空心莲子草的假隔链格孢(Nimbya alternantherae)和镰刀菌(Fusarium sp.),侵染小飞蓬的弯孢(Curvularia sp.)和链格孢(Alternaria sp.),侵染阔叶丰花草和胜红蓟的弯孢(Curvularia sp.),侵染三叶鬼针草的弯孢(Curvularia sp.)和黑孢霉(Nigrospora sphaerica),侵染凤眼莲的链格孢(Alternaria sp.)和炭疽菌(Colletotrichum sp.)。  相似文献   

11.
A new disease of peach (Prunus persica Batsch var. vulgaris Maxim.), causing brown, sunken lesions and brownish to blackish brown spots with cracks on peach fruits, was found in Okayama prefecture, Japan, in 1995. The disease was observed not only on peach fruits but also on twigs and leaves. An Alternaria sp. was consistently isolated from these diseased fruits, twigs and leaves. The isolates were pathogenic to peach fruits and leaves. Based on the morphological characteristics, the causal fungus was identified as Alternaria alternata (Fr.) Keissler. After cross-inoculation with isolates from peach, Japanese pear and apple, the isolates were found to be pathogenic only to their original host. This is the first report on a peach disease caused by a host-specific A. alternata; therefore, the common name of black spot (`Kokuhanbyo' in Japanese) was proposed. Received 25 June 1999/ Accepted in revised form 12 October 1999  相似文献   

12.
Brown spot disease on pear caused by Stemphylium vesicarium may affect leaves and fruits. Inoculum sources present on orchard floors play an important role in the epidemiology of pear brown spot. The pathogen can overwinter on plant residues and multiply and spread on the residues during the growing season. In the Netherlands, brown spot characteristically occurs only in a fraction of the orchards per season. Until now, no tools are available for Dutch pear growers to predict the risk of brown spot in specific orchards. As a consequence, preventive fungicide sprayings are common. The concentration of DNA of pear-pathogenic S. vesicarium was quantified by a specific TaqMan-PCR assay for various types of plant residues present on orchard floors to evaluate their importance as potential inoculum source. The pathogen was often found in residues of pear leaves, grasses and weeds, but only occasionally in mummies and prunings. Studies of the population dynamics showed that S. vesicarium decreased in dead pear leaves during early winter whereas pathogen populations developed with irregular pattern during the growing season on residues of weeds and grasses. Based on DNA concentrations of S. vesicarium in plant residue samples taken in 78 to 106 orchards in the springs of 2010, 2011 and 2012, the risk of brown spot development could be predicted for individual orchards. Such a risk prediction will allow growers to adapt their fungicide spray schedules to avoid unnecessary sprays in low-risk orchards.  相似文献   

13.
山茱萸褐斑病病原鉴定   总被引:1,自引:0,他引:1  
 山茱萸(Cornus officinalis)为山茱萸科(Cornaceae)山茱萸属植物, 其成熟干燥果肉(俗称枣皮)为我国常用名贵中药材。河南省南阳市(西峡、内乡和南召等县)为我国山茱萸主产区之一, 仅西峡县截止1990年已发展到500万株, 年产枣皮315万kg, 产值达4 200万元, 居全国首位。近年, 作者对西峡县山茱萸产区进行病害调查时发现, 由链格孢菌(Alternaria sp.)引起的山茱萸褐斑病发生普遍, 该病严重发生时可致植株95%以上叶片枯死, 落果率高达87%, 造成山茱萸大幅减产, 给当地果农带来严重经济损失。迄今, 未见链格孢菌引起的山茱萸病害报道。本研究对该病的病原菌进行分离鉴定, 以期为病害的防控提供依据。  相似文献   

14.
During the last three years, a new disease was observed in northwestern Greece on Minneola trees, hybrid of mandarin and grapefruit. On May small brown necrotic leaf spots surrounded by yellow halo areas of various sizes appeared and covered a major portion of the leaves with extension of necrosis into the veins. On young fruits small, slightly depressed black spots were the first symptoms, which later became 2–7 mm in diameter. Brown spots were observed on the leaves and fruits in several orchards in the same area, causing leaves and fruits to drop. In some orchards over 50% of the fruits were affected. From the fruit and leaf spots the typical small-spore species Alternaria alternata was isolated. Pathogenicity tests were performed by artificially inoculating fruits of Minneola, common mandarin and Clementine. The symptoms of the disease were reproduced only on fruits of Minneola hybrids by the specific strain of the fungus Alternaria alternata pv. citri. Different citrus susceptibility tests indicated that mandarins Minneola, Nova and Page were very susceptible to tested isolates while Clementine SRA and Poros Clementine were not. All lemons and lime Seedless were not susceptible. Grapefruit New Hall was not susceptible, while the Star Ruby was. Orange Lane Late, Navel Late, Oval Poros, Olinda, Navel Athos were not susceptible and only Moro showed reaction being slightly susceptible only to one isolate.  相似文献   

15.
欧李[ Cerasus humilis( Bge.) Sok.]为蔷薇科樱桃属果树,别名钙果,原产中国,分布于我国的黑龙江、辽宁、内蒙古、河北、山东、山西等省区.多生长在向阳山坡或沙丘边缘,资源相当丰富.欧李株高0.3~1.5m,多为0.5~0.7m左右,是目前世界上最矮小的木本果树.果实可鲜食或加工,含糖、蛋白质、维生素C,特别是矿质元素铁和钙的含量很高,每100果肉干分别含有58和360 mg种仁可作药用,中药称之为"郁李仁"可消毒化肿.  相似文献   

16.
烟草不同发育阶段对赤星病的抗性表现与综合防治技术   总被引:4,自引:0,他引:4  
人工接种结果表明,随着烟叶自下而上逐渐成熟、衰老,抗病性下降。不同抗性类型的品种,其绿色叶片对病害均表现免疫或近免疫,近成熟叶片高抗,成熟衰老叶片表现为感病,与品种田间抗病性结果一致。田间结果表明,采用增施钾肥、适时打顶和下部叶片近成熟期摘除1~3片底脚叶等措施,提高烟草品种抗病性、配合有效的农药品种综合防治烟草赤星病,在重病区布局抗病品种能有效地推迟病害的发生时期,减慢病情的发展速度,且能减少农药施用量和施用次数,减少环境污染。  相似文献   

17.
Stemphylium vesicarium (teleomorph: Pleospora herbarum) is the causal agent of brown spot disease in pear. The species is also able to cause disease in asparagus, onion and other crops. Saprophytic growth of the fungus on plant debris is common. The objective of this study was to investigate whether isolates of S. vesicarium from different hosts can be pathogenic to pear. More than hundred isolates of Stemphylium spp. were obtained from infected pear fruits, dead pear leaves, dead grass leaves present in pear orchard lawns as well as from necrotic leaf parts of asparagus and onion. Only isolates originating from pear orchards, including isolates from dead grass leaves, were pathogenic on pear leaves or fruits in bioassays. Non-pathogenic isolates were also present in pear orchards. Stemphylium vesicarium from asparagus or onion, with one exception, were not pathogenic to pear. Analysis of the genetic variation between isolates using Amplified Fragment Length Polymorphism (AFLP) showed significant concordance with host plants. Isolates from asparagus or onion belonged to clusters separate from the cluster with isolates from pear or grass leaves collected in pear orchards. Multilocus sequencing of a subset of isolates showed that such isolates were similar to S. vesicarium.  相似文献   

18.
Farmers' fields were surveyed for a new disease on broad bean in different parts of Shimane Prefecture. The disease was found in all surveyed fields. The fungus frequently associated with diseased broad bean leaves having the characteristic leaf spot symptom was identified as Alternaria tenuissima, based on morphological characteristics. The initial lesion was brown, water soaked, circular to slightly irregular. Then the lesion enlarged and became concentric. Mature leaves had coalescing necrosis surrounded by yellowing. Older leaves of the plant were particularly affected. In a later stage of the disease, the leaves became blighted from the margin to the center and most of the diseased plants defoliated. In severely infected fields, circular to irregularly shaped lesions also appeared on stems and pods, and plants defoliated completely. All tested isolates were pathogenic to broad bean leaves. Different isolates of the fungus varied in pathogenicity on different broad bean cultivars. In a comparison of symptoms of the disease and morphological characteristics of the isolated fungus with other broad bean diseases, this disease represented a new, as yet undescribed disease of broad bean in Japan. Therefore, we propose the name "leaf spot of broad bean" and "Soramame hanten-by?" in Japanese. Received 12 April 2001/ Accepted in revised form 18 October 2001  相似文献   

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