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1.
苹果炭疽叶枯病菌CgCMK1基因的克隆与功能分析 总被引：1，自引：0，他引：1
苹果炭疽叶枯病是由胶孢炭疽菌(Colletotrichum gloeosporioides)引起的苹果重要叶部病害,严重威胁苹果树的生长。CMK1-MAPK途径在植物病原真菌致病过程中具有重要的作用。本研究从苹果炭疽叶枯病菌中克隆了黄瓜炭疽病菌(C. lagenarium)CMK1的同源基因CgCMK1。CgCMK1基因ORF全长1 068 bp,编码355个氨基酸。CgCMK1敲除后不影响苹果炭疽叶枯病菌营养生长、色素沉积以及脂滴的转运。ΔCgCMK1突变体产孢能力显著下降、分生孢子萌发但不产生附着胞,外源添加cAMP不能诱导ΔCgCMK1突变体形成附着胞,在ΔCgCMK1突变体中,过表达cAMP信号途径依赖的蛋白激酶催化亚基基因CgCPK1也不能恢复突变体形成附着胞。CgCMK1基因参与氧化胁迫的应答反应,但不参与离子胁迫的应答反应。ΔCgCMK1突变体对苹果叶片完全丧失致病性,即使有伤接种也不能产生病斑。CgCMK1在苹果炭疽叶枯病菌分生孢子和附着胞中均有表达,定位于细胞质。上述结果表明,CgCMK1参与调控苹果炭疽叶枯病菌的分生孢子产量、附着胞的形成、氧化胁迫应答及致病性。 相似文献
2.
苹果炭疽叶枯病是主要由胶孢炭疽菌(Colletotrichum gloeosporioides)引起的一种苹果重要叶部病害,严重威胁着苹果树的生长。本研究从构建的苹果炭疽叶枯病菌T-DNA突变体库中筛选获得一株致病力缺失的突变菌株A3083,采用hiTAIL-PCR方法克隆了该突变体T-DNA插入位点的右翼序列;通过与胶孢炭疽菌基因组序列比对分析,发现T-DNA插入位点位于1个预测的CGGC5_9603基因内,并将该基因命名为CgNVF1。CgNVF1基因全长2252 bp,含有2个内含子,编码709个氨基酸。CgNVF1定位于细胞质,在苹果炭疽叶枯病菌菌丝、分生孢子和附着胞中均有表达。通过构建CgNVF1敲除菌株和CgNVF1互补菌株,并结合表型分析,证实CgNVF1基因在苹果炭疽叶枯病菌附着胞形成及致病中具有重要的作用。 相似文献
3.
G蛋白信号调控因子(regulators of G-protein signaling,RGS)是G蛋白的一类负调控因子,在植物病原真菌生长发育及致病过程中起着重要作用。为探究胶孢炭疽病菌1个RGS基因CgRGS3的生物学功能,利用PCR技术扩增CgRGS3基因并进行生物信息学分析,通过同源重组的方法获得该基因的敲除突变体,并在突变体的基础上获得互补株,通过表型分析确定CgRGS3的生物学功能。结果表明:CgRGS3编码1个含有367个氨基酸的蛋白,包含1个RGS功能域和3个跨膜区域,表型分析发现与野生型菌株相比,敲除突变体营养生长缓慢,分生孢子产量附着胞形成率显著降低,对Cu~(2+)、Fe~(2+)、Zn~(2+)离子更加敏感,细胞壁完整性发生改变,黑色素产量降低及致病力减弱等。由此可见,CgRGS3参与调控胶孢炭疽菌的营养生长,分生孢子产生及附着胞的分化、细胞壁完整性、黑色素产生及致病性等。 相似文献
4.
解淀粉芽胞杆菌TS-1203对苹果炭疽叶枯病菌的抗生作用 总被引：1，自引：0，他引：1
为明确解淀粉芽胞杆菌TS-1203对苹果炭疽叶枯病菌的抗生作用, 采用平板对峙法和菌丝生长速率法以及孢子萌发法测定了解淀粉芽胞杆菌TS-1203对苹果炭疽叶枯病菌菌落生长和孢子萌发的抑制作用?结果表明:菌株TS-1203对苹果炭疽叶枯病菌具有显著的抑制作用, 其菌液对病菌的抑制率高达70.4%; 其发酵液对苹果炭疽叶枯病菌的抑制率随着发酵液浓度的增加而升高, 尤其当发酵液浓度为15%时, 其抑菌率为 59.0%; 发酵液处理苹果炭疽叶枯病菌孢子24 h后, 其萌发抑制率与芽管生长抑制率分别为78.2%与64.3%, 且芽管出现畸形; 利用TS-1203发酵液处理苹果离体叶片后接种炭疽叶枯病菌, 其防效为70.1%?综合分析表明, 解淀粉芽胞杆菌TS-1203对苹果炭疽叶枯病菌具有良好的抑制作用? 相似文献
5.
苹果炭疽叶枯病(Glomerella cingulata)是我国苹果上新发现的一种病害,为了了解病原菌的产孢条件和产孢动态,为病害的预测预报与防控提供依据。本研究在人工控制条件下,测试了温度、湿度和光照对苹果炭疽叶枯病菌产生分生孢子和子囊孢子的影响。结果表明,苹果炭疽叶枯病新形成的病叶润湿后,在15℃~30℃下保湿培养2~6 d后可产生大量橘黄色的分生孢子堆,其中30℃下产孢量最大,产孢速度最快,仅需2 d时间。炭疽叶枯病菌在新形成的病叶上于15℃~30℃下培养20~30 d可形成子囊孢子,最适温度为25℃,子囊孢子的形成需要高湿环境或叶片润湿。炭疽叶枯病菌的单孢分离菌株于15℃~25℃下,在马铃薯葡萄糖琼脂培养基(PDA)上培养20~30 d也可形成子囊孢子,最适产孢温度25℃。紫外光、黑光和日光都能促进子囊孢子的形成。 相似文献
6.
MoHRD3基因参与调控稻瘟病菌的生长发育和致病力 总被引：1，自引：0，他引：1
稻瘟病菌(Magnaporthe oryzae)作为主要的农业病原微生物,其引起的稻瘟病严重威胁着水稻等谷类作物的生产安全。内质网相关蛋白质降解途径(Endoplasmic reticulum-associated protein degradation, ERAD)是生物体应答内质网压力的主要方式之一,其在机体生长发育过程中具有重要作用。而HRD(HMG-CoA reductase degradation)复合物作为ERAD的关键组分,主要由Hrd1、Hrd3、以及凝集素Yos9等蛋白组成,负责内质网中错误折叠蛋白的识别、转运以及泛素化过程,最终由蛋白酶体降解,从而有效缓解内质网压力,保证细胞的正常生理活动。有研究表明,Hrd3属于单次跨膜蛋白,在内质网腔中与Hrd1、Yos9相结合,负责底物的识别并起着稳定Hrd1的作用。目前Hrd3在稻瘟病菌中的生物学功能尚不清楚。本研究通过基因敲除及互补试验获得了稻瘟病菌的ΔMohrd3突变体和ΔMohrd3-C回补菌株,并以野生型为对照,对突变体的生物学表型进行了分析。结果显示,ΔMohrd3突变体的生长速率、产孢量明显下降;对大麦和水稻的致病力显著减弱。进一步胁迫试验表明,MoHRD3的缺失导致稻瘟病菌对外界盐胁迫、渗透压胁迫的耐受性增强,对内质网胁迫耐受性减弱,而对细胞壁胁迫无明显变化。同时,MoHRD3基因的缺失激活了未折叠蛋白响应途径(Unfolded protein response, UPR)。上述结果表明,MoHRD3参与调控稻瘟病菌的营养生长、无性繁殖、致病及对不同环境胁迫的响应过程。 相似文献
7.
8.
稻瘟病菌(Magnaporthe oryzae)作为主要的农业病原微生物,其引起的稻瘟病严重威胁着水稻等谷类作物的生产安全。内质网相关蛋白质降解途径(Endoplasmic reticulum-associated protein degradation, ERAD)是生物体应答内质网压力的主要方式之一,其在机体生长发育过程中具有重要作用。而HRD(HMG-CoA reductase degradation)复合物作为ERAD的关键组分,主要由Hrd1、Hrd3、以及凝集素Yos9等蛋白组成,负责内质网中错误折叠蛋白的识别、转运以及泛素化过程,最终由蛋白酶体降解,从而有效缓解内质网压力,保证细胞的正常生理活动。有研究表明,Hrd3属于单次跨膜蛋白,在内质网腔中与Hrd1、Yos9相结合,负责底物的识别并起着稳定Hrd1的作用。目前Hrd3在稻瘟病菌中的生物学功能尚不清楚。本研究通过基因敲除及互补试验获得了稻瘟病菌的ΔMohrd3突变体和ΔMohrd3-C回补菌株,并以野生型为对照,对突变体的生物学表型进行了分析。结果显示,ΔMohrd3突变体的生长速率、产孢量明显下降;对大麦和水稻的致病力显著减弱。进一步胁迫试验表明,MoHRD3的缺失导致稻瘟病菌对外界盐胁迫、渗透压胁迫的耐受性增强,对内质网胁迫耐受性减弱,而对细胞壁胁迫无明显变化。同时,MoHRD3基因的缺失激活了未折叠蛋白响应途径(Unfolded protein response, UPR)。上述结果表明,MoHRD3参与调控稻瘟病菌的营养生长、无性繁殖、致病及对不同环境胁迫的响应过程。 相似文献
9.
由辣椒尖孢炭疽菌(Colletotrichum acutatum)侵染引起的炭疽病是辣椒生产中最具有破坏性的真菌病害,严重影响辣椒的品质和产量。本研究以辣椒尖孢炭疽病菌HHDL02为对象,采用1 mol·L-1 NH4Cl 2%的酶裂解液裂解分生孢子萌发2 h的芽管,裂解2～3 h可以高效制备原生质体,结合PEG介导转化法成功将GFP基因导入,其转化菌株菌落形态、菌丝生长速率、分生孢子形态、孢子萌发、附着胞形成、产孢量和致病性与野生型菌株无明显差异,且后代荧光信号遗传稳定。PEG介导的原生质体转化适合辣椒尖孢炭疽菌遗传操作,有助于其致病机理的研究。 相似文献
10.
为明确苹果炭疽叶枯病病原菌围小丛壳Glomerella cingulata的侵染致病特征,在分离获得该病原菌的基础上,采用形态学观察、ITS序列分析和致病性测定对其进行了鉴定,并利用光学和扫描电子显微镜对病原菌在嘎啦苹果叶片上的侵染过程进行了研究.结果表明,在陕西咸阳地区分离获得的9株病原菌均为围小丛壳G.cingulata.25 ℃下接种9 h后,分生孢子中间产生隔膜,双胞化,并萌发产生芽管和附着胞;24 h后分生孢子的2个细胞均可萌发并形成芽管及附着胞,部分芽管顶端可产生次级分生孢子;48 h后次级分生孢子萌发形成附着胞;72 h后,附着胞下形成的侵染钉可直接入侵寄主,在表皮细胞内形成初生菌丝和次生菌丝,此时叶片表面已出现褐色斑点.接种7 d后叶片病斑处出现分生孢子盘和子囊壳.表明陕西省近年出现的苹果炭疽叶枯病病原菌为围小丛壳G.cingulata,该病菌在嘎啦叶片上的一些特殊侵染行为可能是导致该病害易在短时间内暴发的重要原因. 相似文献
11.
Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. is an important fungal pathogen known to cause glomerella leaf spot (GLS). The objective of this study was to analyze the infection of C. gloeosporioides on leaves of apple cv. Fuji (resistant) and cv. Gala (susceptible) and apply proteomics techniques to study the apple defense responses 48 h after inoculation (h.a.i.). On both of cultivars, C. gloeosporioides started to germinate at 3 h.a.i. on adaxial surface and produced appressoria adhering to epidermal cell juxtapositions. Histological analysis showed more stratified parenchyma in leaves of cv. Fuji than cv. Gala associated with differences in the chemical composition of cell walls. Total and unique proteins expressed by cvs. Fuji and Gala at 3, 12, 24 and 48 h.a.i. were detected by comparative proteomes analysis. A total of 42 unique proteins expressed at 24 and 48 h.a.i. were identified by MALDI/TOF mass spectrometry, and most of these proteins were identified as directly involved in defense responses. 相似文献
12.
ABSTRACT Morphological characteristics and vegetative compatibility groups (VCGs) of 486 isolates of Glomerella cingulata, Colletotrichum gloeosporioides, and C. acutatum collected from apple leaves with Glomerella leaf spot (GLS) symptoms and fruit with bitter rot symptoms in the United States and Brazil were studied. From this collection, 155 isolates of G. cingulata (93 from fruit, 61 from leaves, and 1 from buds), 42 isolates of C. gloeosporioides from fruit, and 14 isolates of C. acutatum (10 from fruit and 4 from leaves) were studied using mitochondrial (mt)DNA restriction fragment length polymorphism (RFLP) haplotypes. A subset of 24 isolates was studied by examining the sequence of a 200-bp intron of the glyceraldehyde 3-phosphate dehydrogenase (GDPH) nuclear gene. In addition, 98 isolates were tested for pathogenicity on leaves of cvs. Gala and Golden Delicious in the greenhouse, and 24 isolates were tested for pathogenicity on fruit of cv. Gala in growth chambers. In total, 238 and 225 isolates of G. cingulata were separated into four distinct morphological types and six VCGs, respectively. Five morphological types and six VCGs were identified among 74 and 36 isolates of C. gloeosporioides, respectively. Three morphological types and four VCGs were identified among 74 and 23 isolates of C. acutatum, respectively. Seven different mtDNA RFLP haplotypes were observed within isolates of G. cingulata, two within isolates of C. gloeosporioides, and two within isolates of C. acutatum. Phylogenetic trees, inferred based on maximum likelihood and maximum parsimony methods using the intron sequence, produced similar topologies. Each species was separated into distinct groups. All isolates tested were pathogenic on fruit, though only isolates with specific VCGs and haplotypes were pathogenic to leaves. Vegetative compatibility was a better tool than molecular characters for distinguishing isolates of G. cingulata pathogenic on both leaves and fruit from the ones pathogenic only on fruit. Isolates of G. cingulata capable of causing both GLS and bitter rot were included in haplotypes and groups based on the sequence analysis of the 200-bp intron that also included isolates capable of causing bitter rot only. Additionally, isolates of G. cingulata from the United States and Brazil which cause GLS were included in different haplotypes and sequence analysis groups. Therefore, one hypothesis is that isolates of G. cingulata from the United States capable of causing both GLS on foliage and bitter rot on fruit may have arisen independently of Brazilian isolates of G. cingulata capable of causing both GLS and bitter rot, and the two groups of isolates may represent distinct populations. 相似文献
13.
Ulvan is an algal polysaccharide known for its ability to induce resistance to plant diseases such as the Glomerella leaf spot of apple caused by Colletotrichum gloeosporiodes. This study was aimed at investigating microscopically, in tests in vitro and in vivo, whether ulvan interferes in the development of pre-infective structures of C. gloeosporioides. Conidial germination and appressoria formation were monitored hourly on agar and cellophane, and at 48 h on water- and ulvan-treated susceptible as well as resistant apple leaves. Amendment of agar with ulvan (10 mg ml?1) enhanced the germination and resulted in longer germ tubes at 7 h of incubation. On cellophane it significantly delayed appressoria formation up to 8 h, but later after 14 h increased the number of appressoria per conidium. Spraying of susceptible leaves with ulvan 6 days before inoculation decreased disease severity by 50%. This was associated with inhibition of appressoria formation and stimulus in growth of germ tubes, without interfering with conidial germination, when compared with both water-treated control and resistant plants. Appressorium formation occurred preferentially on anticlinal walls of epidermal cells and its location was not influenced by host resistance or by ulvan treatment. This study suggests a new mode of action for ulvan interfering with appressorium formation that could protect apple plants against C. gloeosporioides infection. 相似文献
14.
Epidemics of apple powdery mildew were monitored on leaves of vegetative extension shoots in a mixed-cultivar orchard in 1979. 1980 and 1981. Cultivars Cox's Orange Pippin. Golden Delicious. Ida Red and Suntan were very susceptible but little mildew developed on cv. Discovery in any year. Results with cvs Crispin and Spartan were less consistent due, in part, to differing patterns of vegetative growth. The rankings of cultivars for disease incidence (proportion of leaves with mildew), number of colonies and mildewed area were similar, and were also consistent on fungicide-sprayed and unsprayed trees in 1981. Less disease occurred on fungicide-treated Golden Delicious than on Cox's Orange Pippin. Most infections occurred on the rolled leaves at the shoot tip. Spore production was greatest on leaves at positions -1 to -4 where leaf 0 was the youngest and leaf - 1 the adjacent and older unrolled leaf. 相似文献
15.
从波斯婆婆纳发病植株上采得的胶孢炭疽菌菌株QZ－97a，经种下寄主专化性研究，可进一步鉴定为胶孢炭疽菌婆婆纳专化型（Colletotrichum gloeosporioides Penz Sacc.f.sp.veronicae S.Qiang et Q.Zeng）。通过扫描电镜观察，发现它在波斯婆婆纳叶片上6h后开始萌发，12h开始形成附着胞，菌丝侵入表皮的位置不仅是气孔，还有表皮细胞连接处，42h叶片就开始溃烂。菌株QZ－97a的专化性强，侵染速度快，侵染力较强，再次表明它具有开发为真菌除草剂的潜力。 相似文献
16.
砂仁叶枯病是一种发生普遍而严重的病害。该病有四种症状类型:叶枯型、斑枯型、星斑型和叶鞘病斑。以前者为主。根据病原菌的形态、培养性状、致病性及寄主范围鉴定为围小丛壳菌(Clomerella cingulata (Stonem.) Spauld.et Schrenk),分生孢子阶段为盘长孢状刺盘孢(Co-lletotrichum gleosporioides (Penz.) Sacc.)。病菌生长量和产孢量依培养和光照条件而异。寄主范围广,在参试的23科39种植物中,有9科15种植物发病。 相似文献
17.
ABSTRACT The causal organism responsible for the recent outbreak of almond and peach anthracnose in California was identified and characterized as Colletotrichum acutatum. Isolates of C. acutatum from almond were found to be similar to California strawberry isolates and South Carolina peach and apple isolates of C. acutatum based on conidial morphology, temperature relationships, fungicide sensitivity, and polymerase chain reaction (PCR) methods using DNA species-specific primers. On almond, blossoms and immature or mature fruit were affected by the disease, causing direct losses of crop. On peach, the disease was observed only on mature fruit. Pathogenicity of almond and peach isolates of C. acutatum was demonstrated on wound- and nonwound-inoculated almond or peach fruit by fulfilling Koch's postulates. Conidial morphology of isolates was variable, depending on the medium or substrate used to culture the isolates. Isolates of C. acutatum from strawberry, almond, and peach were grouped together based on a similar response to temperature, with an optimal growth rate at 25 degrees C (generally less than 10 mm/day), whereas isolates of C. gloeosporioides from citrus and papaya had an optimal growth rate at 30 degrees C (generally greater than 10 mm/day). In fungicide disk assays, isolates of C. acutatum from strawberry, peach, and apple, as well as almond and peach isolates from California, were less sensitive to benomyl at 300, 600, or 1,200 mug/ml. In contrast, C. gloeosporioides isolates from citrus and papaya were very sensitive to benomyl at all concentrations evaluated. All isolates of both species were sensitive to captan (300, 600, or 1,200 mug/ml). Oligonucleotide primers were synthesized for C. acutatum, C. fragariae, or C. gloeosporioides using published DNA sequences from the internal transcribed spacer 1 region of ribosomal DNA. Thirty-two Colletotrichum isolates from almond fruit produced DNA products with a C. acutatum primer (CaInt-2) that matched products and approximate molecular weight of known C. acutatum isolates. No PCR products were produced with primers for C. gloeosporioides or C. fragariae. Isolates from citrus and papaya produced DNA products only with primers from C. gloeosporioides or C. fragariae. Thus, worldwide, anthracnose of almonds may be caused by either C. gloeosporioides, as previously reported, or by C. acutatum, as indicated in this study. 相似文献
18.
枯草芽孢杆菌BS80-6对苹果采后炭疽病的控病效果及作用机制 总被引：6，自引：3，他引：3
为提高枯草芽孢杆菌的生防效果,通过离子束诱变筛选出BS80-6菌株.利用生物测定方法研究BS80-6菌株及不同处理方法在不同贮藏温度下对采后苹果炭疽病的控制效果和作用机制.结果表明,BS80-6能显著提高对苹果炭疽菌的抑制作用.枯草芽孢杆菌BS80-6对苹果果实炭疽病的防治效果以活菌液效果最好,菌丝生长抑制率为80.14%,孢子萌发抑制率为98.65%,控病效果为60.34%;灭菌液和过滤液对苹果炭疽菌也有一定的抑制效果.贮藏温度明显影响BS80-6对苹果炭疽病的防治效果;接种方式对控病效果影响显著,先接拮抗菌再接病菌的防效好于先接病菌再接拮抗菌. 相似文献
19.
HOG-MAPK(high osmolarity glycerol mitogen-activated protein kinase)信号途径是真菌MAPK途径中参与渗透压响应的一条重要通路,在植物病原菌生长发育及致病过程中发挥着重要的作用。Sho1(synthetic high osmolarity-sensitive protein1)是HOG-M APK信号途径上游的一个重要感受器,在不同真菌中常具有不同的功能。本研究从胶孢炭疽菌中克隆了Sho1的同源基因,命名为Cg Sho1,该基因编码一个291个氨基酸的蛋白,含有4个跨膜结构域和一个SH3功能域。利用同源重组的方法获得了该基因的敲除突变体,与野生型相比,敲除突变体表现为营养生长缓慢,菌丝稀疏且疏水性增强,产孢量下降,对氧化压力和渗透压更加敏感,致病力明显减弱。上述结果表明,Cg Sho1参与调控胶胞炭疽菌的营养生长、分生孢子产量、氧化应激反应、渗透压响应及致病性。 相似文献