共查询到10条相似文献，搜索用时 171 毫秒
1.
“早衰”是高粱生产和育种上存在的普遍现象。长期以来被认为是一种生理性病害。经4年研究证明它是草酸青霉(Penicilliem axalicum)和纤细交链孢霉(Allernaria allernala)于初花期浸染而引起的一种高粱穗部病害。主要症状是颖壳及与其连接的枝梗组织坏死,阻止了养分、水分向上输导,造成籽粒秕瘦变小。一般减产10％以上。这是国内首次报道的高粱新病害,定名为高粱青霉颖枯病,此病在初花期用多菌灵防治有较好效果。 相似文献
2.
In June 1995, a disease causing round to irregular-shaped, water-soaked, brown to blackish brown spots on mealycup sage (Salvia farinacea Benth.) was found in Atsugi-shi, Kanagawa Prefecture, Japan. The symptoms were seen only on leaves, not on neither flower
petals or stems. The disease was also found in Setagaya-ku, Tokyo, Memambetsu-cho, Hokkaido and Shimoda-shi and Matsuzaki-cho,
Shizuoka. An Alternaria sp. was frequently isolated from these diseased plants. The isolates were severely pathogenic to mealycup sage and caused
lesions on the inoculated leaves. The isolates were also weakly pathogenic on scarlet sage (S. splendens Sellow ex Roem. and Schult.) but not on any other Labiatae plants tested. Based on morphological characteristics, such as
size of conidia, chain number, and the short beak on conidia, the causal fungus was identified as Alternaria alternata (Fr.) Keissler. This report is the first on a mealycup sage disease caused by A. alternata. Because the symptom was restricted to the leaf, the common name of Alternaria leaf spot was proposed.
Received 30 August 2002/ Accepted in revised form 18 November 2002 相似文献
3.
百香果疮痂病病原菌鉴定 总被引：1，自引：0，他引：1
To identify the pathogen causing scab disease on the fruit of Passiflora Linn. in the passion fruit yard of Cenxi and Nanning cities, Guangxi province. The scab tissues collected from diseased fruits were isolated,purified,and made pathogenicity test,morphological observation, biological and molecular identification. The representive isolate B31, obtained from the diseased fruit, was selected for morphological observation and pathogen identification, and was verified as the causal agent of the scab disease through Koch’s postulates. The result of morphological observation using light microscope showed that the isolate B31 was very similar to Alternaria in terms of hyphae and spore morphology. Phylogenetic analysis results using multiple gene loci showed that identities of sequences of ITS, Alt al, TEF 1 and endoPG genes of isolate B31 were 100% identical to those of Alternaria alternata. This study clarifies that the pathogen causing scab disease of passion fruit in Guangxi is A. alternata, and this is the first report of A. alternate causing scab on passion fruit in China. 相似文献
4.
茶树链格孢叶斑病的病原鉴定 总被引：3，自引：0，他引：3
茶树是我国重要的经济作物,茶园叶病的流行会造成严重的经济损失。2017年10月到2018年1月从安徽、福建和湖北省茶区的9个茶树品种上采集代表性茶叶斑病叶,该病害的发病症状与由Colletotrichum spp.引起的茶炭疽病相似。采用组织分离法从发病叶片组织分离获得26株菌落形态一致的真菌分离物,显微镜观察结果显示,各菌株分生孢子的产生方式和形态特征相似。为进一步明确菌株的分类地位,选取2株来自安徽庐江和宣城地区的代表性菌株(EC-6和XBC1-3)进行多基因片段的PCR扩增和序列分析。结果表明,代表性菌株EC-6和XBC1-3的ITS、gpd、tef-1a基因序列分别与交链格孢Alternaria alternata参考菌株CBS 107.27的序列(KP124300, KP124157, KP125075)相似性为100%、99%和100%,结合菌株形态学观察以及柯赫氏法则验证,证实交链格孢是引起该茶树叶斑病的致病菌。这是在安徽茶区首次发现由致病性链格孢引起茶树叶斑病。 相似文献
5.
A new disease of pelargonium (Pelargonium domesticum Bailey), ivy geranium (P. peltatum (L.) L'Hér. ex Ait.) and scented geranium (P. graveolens L'Hér.), primarily causing brown spots on leaves, was found in Kawasaki-shi in Kanagawa Prefecture and Tachikawa-shi in Tokyo.
An Alternaria sp. was consistently isolated from these diseased leaves, and the isolates were pathogenic to their host leaves. Based on
morphological characteristics, the causal fungus in all three cases was identified as Alternaria alternata (Fr.) Keissler. Because Alternaria leaf spot of geranium by A. alternata has already been reported, the pathogenicity of isolates from four groups of genus Pelargonium was investigated. The isolates from scented geranium were pathogenic only to their original host, but the isolates from pelargonium,
ivy geranium and geranium were pathogenic to all groups of pelargonium. This is the first report of this disease on pelargonium,
ivy geranium and scented geranium caused by A. alternata in Japan. We propose the names for these diseases as Alternaria leaf spot of pelargonium (kappan-byo), Alternaria leaf spot
of ivy geranium (kappan-byo) and Alternaria leaf spot of scented geranium (kappan-byo).
Received 11 December 2000/ Accepted in revised form 19 July 2001 相似文献
6.
壶瓶枣褐斑病病原菌的鉴定 总被引：1，自引：0，他引：1
近几年来,山西红枣发生了1种严重的果实病害,症状表现为果顶或果肩部位形成红褐色的病斑。本研究以壶瓶枣为材料,对病菌进行分离。通过室内和田间致病性测定以及人工接种后再分离病菌,证明编号为CN535的真菌菌株为该病的致病菌。该病菌在PDA上7d菌落直径达69.2~73.5mm,基内菌丝和气生菌丝均发达,具明显的浅灰与墨绿色的同心轮纹;分生孢子单生或短链生,具纵横隔膜和短喙,大小为(22.5~40.0)μm×(8.0~13.5)μm,为典型的Alternaria属真菌特征。其rDNAITS序列分析结果表明该菌与A. alternata、A. tenuissima、A. longipes、A. mali和A. citri的同源性均为100%。用2对链格孢菌的专用引物AAF2/AAR3和Aalt-F/Aalt-R分别扩增出相对应的341和450bp的片段。综合形态特征和分子分析结果,确定壶瓶枣褐斑病的病原菌为A. alternata (Fries) Keissler。 相似文献
7.
8.
2019年-2020年在北京地区桃园病害调研普查时发现一种桃树病害的新发症状-新叶坏死,主要症状表现为当年新生枝条顶端新叶和生长点腐烂坏死。为明确这种新叶坏死症状是否由病原菌侵染引起,从北京平谷2个乡镇3个桃园采集35份病梢样品,经病样组织分离和菌株纯化,选取12个代表性菌株进行形态学鉴定、系统进化分析以及致病性测定。结果显示,通过形态学鉴定和多基因(ITS,Alt a1,gpd)系统发育分析,以上分离株均鉴定为链格孢Alternaria alternata;3株代表性菌株的致病性测定验证了A.alternata是引起新叶坏死症状的病原菌,并且该病原菌也能导致桃枝条和果实发病,产生黑斑病症状。这是首次报道A.alternata除了引起桃果实黑斑症状之外,还可以引起桃树新叶坏死症状,结果进一步丰富了链格孢侵染桃树的症状多样性,为链格孢引起的病害的整体防控提供了理论基础。 相似文献
9.
木霉几丁质酶对烟草赤星病菌的作用 总被引：10，自引：0，他引：10
以指形管培养法分别测定几丁质酶粗酶液和纯化的几丁质酶混合液(2种几丁质酶)对烟草赤星病菌孢子萌发的抑制作用。结果表明,较高浓度(25 2U)几丁质酶粗酶液在48h内强烈抑制孢子萌发和芽管伸长,或致芽管畸形和细胞壁破裂;几丁质酶混合液对赤星病菌的孢子萌发也表现出明显的抑制作用,但在相同或相近酶活性条件下,纯化的几丁质酶混合液(9 4U)和粗酶液(12 6U)对赤星病菌孢子萌发的抑制率(处理24h时)分别为46%和84 3%,前者明显低于后者。采用孢子液悬滴法接种烟苗(K 326)叶片测定木霉几丁质酶对赤星病菌致病性的影响。结果表明,几丁质酶粗酶液浓度越高,对孢子萌发抑制时间越长,抑制率越高;其浓度为4 9、9 8、19 5U/ml的抑制率7d时分别为36 8%、56 2%和57 6%。 相似文献
10.
SALAMIAH Hajime AKAMATSU Yukitaka FUKUMASA-NAKAI Hiroshi OTANI Motoichiro KODAMA 《Journal of General Plant Pathology》2001,67(2):97-105
The genetic controls of host-specific toxin (HST) biosynthesis and the pathogenicity of A. alternata pathogens have been limited by the asexual nature of the life cycle of these fungi. We used a protoplast fusion system for
A. alternata to analyze the genetics of HST production and its relation to the specific pathogenicity of these pathogens. Drug-resistant
transformants were isolated by genetic transformation, using vectors conferring resistance to hygromycin B and geneticin,
for the A. alternata apple pathotype (AM-toxin producer) and A. alternata tomato pathotype (AAL-toxin producer), respectively. Protoplasts of the respective transformants were fused by electrofusion.
The majority of resultant stable fusants produced both AM- and AAL-toxins and were pathogenic to susceptible cultivars of
both apple and tomato. Pulsed-field gel electrophoresis analysis demonstrated that these fusants (or hybrids) carried small
1.7-and 1.1-Mb chromosomes, characteristic of the parental strains of the apple and tomato pathotypes, respectively. Detection
of the AMT gene, involved in AM-toxin biosynthesis, by polymerase chain reaction revealed that all fusants pathogenic to apple maintained
this gene. Microfluorimetry analysis using propidium iodide staining suggested that the fusants might be diploid.
Received 14 November 2000/ Accepted in revised form 11 December 2000 相似文献