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1.
ABSTRACT Isolates of Colletotrichum spp. from almond, avocado, and strawberry from Israel and isolates of the pink subpopulation from almond from the United States were characterized by various molecular methods and compared with morphological identification. Taxon-specific primer analysis grouped the avocado isolates within the species C. gloeosporioides and the U.S. almond and Israeli strawberry isolates within the species C. acutatum. However, the Israeli almond isolates, previously identified morphologically as C. gloeosporioides, reacted with C. acutatum-specific primers. Arbitrarily primed polymerase chain reaction and A+T-rich DNA analyses determined that each population from almond and strawberry was distinct and clonal. Sequence analysis of the complete internal transcribed spacer (ITS) region (ITS 1-5.8S-ITS 2) revealed a similarity of between 97.03 and 98.72% among almond isolates from Israel, C. acutatum almond isolates from the United States, and C. acutatum strawberry isolates from Israel. Similarity of the above populations to that of C. gloeosporioides of avocado was between 92.42 and 92.86%. DNA sequence analysis of the entire ITS region supported the phylogeny inferred from the ITS 1 tree of 14 different Colletotrichum species. Although morphological criteria indicated that the Israeli isolates from almond are unique, this population was grouped within the C. acutatum species according to molecular analyses. 相似文献
2.
Molecular identification of Colletotrichum gloeosporioides causing yam anthracnose in Nigeria 总被引：2，自引：1，他引：2
M. M. Abang S. Winter † K. R. Green P. Hoffmann H. D. Mignouna G. A. Wolf 《Plant pathology》2002,51(1):63-71
Four forms of Colletotrichum representing three distinct virulence phenotypes were found associated with foliar anthracnose of yam in Nigeria: the highly virulent (= severity of disease) slow-growing grey (SGG); the moderately virulent fast-growing salmon (FGS); the weakly virulent fast-growing grey (FGG); and the moderately virulent fast-growing olive (FGO) morphotype. Isolates of the four forms were identified as C. gloeosporioides , based on morphology. The reaction of monoconidial cultures on casein hydrolysis medium (CHM), PCR-RFLP and sequence analysis of the internal transcribed spacer region of the ribosomal DNA (ITS1-5·8S-ITS2) were used to establish the identity of the yam anthracnose pathogen(s). All yam isolates were distinguished from C. acutatum by the absence of protease activity on CHM. On ITS PCR and enzymatic digestion of PCR products, all FGS, FGO and SGG isolates produced RFLP patterns identical to those of C. gloeosporioides reference isolates, while FGG isolates revealed unique ITS RFLP banding patterns. Sequence analysis of the ITS1 region and of the entire ITS region revealed that SGG, FGS and FGO isolates were highly similar (98–99% nucleotide identity) and showed 97–100% identity to C. gloeosporioides . Less than 93% similarity of these fungal isolates to reference C. acutatum and C. lindemuthianum isolates was observed. The molecular study confirmed that foliar anthracnose of yam is caused by C. gloeosporioides . While a high similarity was found among most C. gloeosporioides fungi from yam, isolates of the FGG form did not cluster with any previously described Colletotrichum species, and probably represent a distinct species. 相似文献
3.
P. P. Than R. Jeewon K. D. Hyde † S. Pongsupasamit O. Mongkolporn P. W. J. Taylor 《Plant pathology》2008,57(3):562-572
Fungal isolates from chilli ( Capsicum spp.) fruits in Thailand that showed typical anthracnose symptoms were identified as Colletotrichum acutatum , C . capsici and C . gloeosporioides . Phylogenetic analyses from DNA sequence data of ITS rDNA and β-tubulin ( tub 2) gene regions revealed three major clusters representing these three species. Among the morphological characters examined, colony growth rate and conidium shape in culture were directly correlated with the phylogenetic groupings. Comparison with isolates of C . gloeosporioides from mango and C . acutatum from strawberry showed that host was not important for phylogenetic grouping. Pathogenicity tests validated that all three species isolated from chilli were causal agents for chilli anthracnose when inoculated onto fruits of the susceptible Thai elite cultivar Capsicum annuum cv. Bangchang. Cross-infection potential was shown by C . acutatum isolates originating from strawberry, which produced anthracnose on Bangchang. Interestingly, only C . acutatum isolates from chilli were able to infect and produce anthracnose on PBC 932, a resistant genotype of Capsicum chinense . This result has important implications for Thai chilli breeding programmes in which PBC 932 is being hybridized with Bangchang to incorporate anthracnose resistance into chilli cultivars. 相似文献
4.
C. Garrido M. Carbú F. J. Fernández-Acero N. Boonham A. Colyer J. M. Cantoral G. Budge 《Plant pathology》2009,58(1):43-51
Real-time PCR (TaqMan®) assays were developed for the specific detection and discrimination of Colletotrichum spp., C. acutatum and C. gloeosporioides causing anthracnose in strawberry using the most divergent area of the internal transcribed spacers (ITS1 and ITS2) and 5·8S ribosomal RNA (rRNA) gene region. The specificity of the new assays was tested using DNA from six species of Colletotrichum and nine fungal species commonly found associated with strawberry material, and additionally by comparing the sequences with those from databases using a blast search. The sequences only showed identity with homologous sequences from the desired target organisms. The new assays were 10–100 times more sensitive than conventional PCR methods previously published for the diagnosis of strawberry anthracnose. When real-time PCR was compared with ELISA methods, PCR improved the sensitivity of the identification by obtaining positive results for samples of strawberry plant material that tested negative with ELISA. The development of C. acutatum was monitored using artificially infected strawberry crowns from two strawberry cultivars (Camarosa and Ventana) and a real-time PCR assay specific for this species between January and June 2006. The amount of C. acutatum detected using real-time PCR varied significantly by month ( P < 0·001), but not by cultivar ( P = 0·394). The new assays were shown to be useful tools for rapid detection and identification of these pathogens and to allow rapid and accurate assessment of the casual agents of anthracnose in strawberry. 相似文献
5.
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
6.
M.P. Martín F. García-Figueres 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(8):733-741
Morphological and cultural features and restriction fragment length polymorphism analysis of ITS regions, including 5.8S rDNA, from 26 isolates of Colletotrichum species revealed that isolates from olive fruits, previously identified as C. gloeosporioides, belong to two taxa: C. acutatum and C. gloeosporioides. Comparison of both ITS sequence data with reference isolates confirmed the presence of both species in olives affected by anthracnose disease. 相似文献
7.
Denoyes-Rothan B Guérin G Délye C Smith B Minz D Maymon M Freeman S 《Phytopathology》2003,93(2):219-228
ABSTRACT Ninety-five isolates of Colletotrichum including 81 isolates of C. acutatum (62 from strawberry) and 14 isolates of C. gloeosporioides (13 from strawberry) were characterized by various molecular methods and pathogenicity tests. Results based on random amplified polymorphic DNA (RAPD) polymorphism and internal transcribed spacer (ITS) 2 sequence data provided clear genetic evidence of two subgroups in C. acutatum. The first subgroup, characterized as CA-clonal, included only isolates from strawberry and exhibited identical RAPD patterns and nearly identical ITS2 sequence analysis. A larger genetic group, CA-variable, included isolates from various hosts and exhibited variable RAPD patterns and divergent ITS2 sequence analysis. Within the C. acutatum population isolated from strawberry, the CA-clonal group is prevalent in Europe (54 isolates of 62). A subset of European C. acutatum isolates isolated from strawberry and representing the CA-clonal and CA-variable groups was assigned to two pathogenicity groups. No correlation could be drawn between genetic and pathogenicity groups. On the basis of molecular data, it is proposed that the CA-clonal subgroup contains closely related, highly virulent C. acutatum isolates that may have developed host specialization to strawberry. C. gloeosporioides isolates from Europe, which were rarely observed were either slightly or nonpathogenic on strawberry. The absence of correlation between genetic polymorphism and geographical origin in Colletotrichum spp. suggests a worldwide dissemination of isolates, probably through international plant exchanges. 相似文献
8.
ABSTRACT This study was conducted to identify the species of Colletotrichum infecting tamarillo, mango, and passiflora in Colombia and to assess whether cross-infection between host species is occurring. Isolates of Colletotrichum spp. from tamarillo (n = 54), passiflora (n = 26), and mango (n = 15) were characterized by various molecular methods and by morphological criteria. Morphological characterization grouped the tamarillo isolates as C. acutatum and the passiflora and mango isolates as C. gloeosporioides. Species-specific primer analysis was reliable and confirmed grouping of the tamarillo isolates (besides Tom-6) as C. acutatum and the mango isolates (besides Man-76) as C. gloeosporioides. However, DNA of the passiflora isolates was not amplified by either C. acutatum- or C. gloeosporioides-specific primers, but reacted with a new primer, Col1, designed according to the internal transcribed spacer (ITS) 1 region of these isolates. Isolates Tom-6 and Man-76 also reacted positively with the Col1 primer. All the isolates reacting with the C. acutatum- and C. gloeosporioides-specific primers failed to react with primer Col1. Isolate Pass-35 from passiflora did not react with any of the taxon-specific primers. Arbitrarily primed polymerase chain reaction (ap-PCR), random amplified polymerase DNA (RAPD)-PCR, and A+T-rich DNA analyses delineated representative isolates into subgroups within the designated species. Molecular analyses indicated that the C. acutatum tamarillo isolates were uniform or clonal, whereas the C. gloeosporioides mango isolates and Colletotrichum passiflora isolates were heterogeneous. Likewise, sequence analysis of the complete ITS (ITS1-5.8S-ITS2) region identified certain isolates to their respective species: tamarillo isolates as C. acutatum; mango isolates as C. gloeosporioides; passiflora, Tom-6, and Man-76 isolates as a Colletotrichum sp. as yet undefined; and the Pass-35 isolate as an additional undefined Colletot-richum sp. Molecular analyses of the population of Colletotrichum isolates from passiflora, Tom-6 from tamarillo, and Man-76 from mango indicate that this population may not be host specific. 相似文献
9.
A total of 264 Stylosanthes spp. plants collected from 78 Stylosanthes spp. populations in seven southern Mexican states were analysed for the presence of Colletotrichum spp. Isolates were obtained from 64 plants collected from 36 Stylosanthes populations; 198 isolates produced straight conidia, while 72 isolates produced falcate conidia. Molecular identification was performed to confirm the identity of C. gloeosporioides for the straight-spored isolates. PCR amplifications using the primer CgInt, synthesized from an ITS1 fragment specific to C. gloeosporioides , and the universal primer ITS4 generated the target fragment for 120 Mexican isolates with straight conidia. The endonucleases Ava II and Sma I were used for restriction of the entire amplified ITS1 region of these 120 isolates. The tree constructed from the restriction data grouped 118 Mexican C. gloeosporioides isolates into three clusters containing reference isolates from Africa and Australia, and generated two additional clusters for two Mexican isolates. Conidial shape and growth rate on solid medium were used as the major morphological criteria for distinguishing types A and B. On the basis of 32 other morphological characteristics, a phenogram grouped the colonies into three main clusters. These clusters were partially related to the Stylosanthes species from which they were isolated, and to the molecular groups. 相似文献
10.
ABSTRACT In recent years, almond anthracnose has developed into a major problem for the California almond industry. The identification of the causal pathogen as Colletotrichum acutatum was confirmed using species-specific primers and restriction fragment length polymorphisms of ribosomal DNA in comparative studies with isolates of C. acutatum from strawberry and C. gloeosporioides from citrus. Two distinct clonal subpopulations among the almond isolates of C. acutatum were identified. These two subpopulations differed in their colony appearance (pink versus gray cultures), conidial morphology, virulence in laboratory inoculation studies, temperature relationships for growth, and molecular fingerprints using random and simple-repeat primers in polymerase chain reactions. Both subpopulations were commonly isolated from the same orchard or even the same fruit. In other orchards, one subpopulation predominated over the other subpopulation. Using random, simple-repeat, and species-specific primers, isolates of the almond anthracnose pathogen from Israel were very similar to the California isolates that produce gray colonies. In addition to fruit, the pathogen was isolated from blighted blossoms, water-soaked or necrotic leaf lesions, symptomless peduncles, and spurs and wood from branches showing dieback symptoms, indicating that the amount of tissue that may be infected is more extensive than previously considered. Overwintering fruit mummies were identified as inoculum sources for early spring infections. Growth studies using almond kernels with different moisture contents indicated that postharvest damage of stored kernels likely originates from preharvest field infections. 相似文献
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12.
Genetic and Pathogenic Analyses of Colletotrichum gloeosporioides Isolates from Strawberry and Noncultivated Hosts 总被引：2，自引：0，他引：2
ABSTRACT Colletotrichum crown rot of strawberry in Florida is caused primarily by Colletotrichum gloeosporioides. To determine potential inoculum sources, isolates of Colletotrichum spp. from strawberry and various noncultivated plants growing in the areas adjacent to strawberry fields were collected from different sites. Species-specific internal transcribed spacer primers for C. gloeosporioides and C. acutatum were used to identify isolates to species. Random amplified polymorphic DNA (RAPD) markers were used to determine genetic relationships among isolates recovered from noncultivated hosts and diseased strawberry plants. Selected isolates also were tested for pathogenicity on strawberry plants in the greenhouse. In all, 39 C. gloeosporioides and 3 C. acutatum isolates were recovered from diseased strawberry crowns, and 52 C. gloeosporioides and 1 C. acutatum isolate were recovered from noncultivated hosts. In crown inoculation tests, 18 of the 52 C. gloeosporioides isolates recovered from noncultivated hosts were pathogenic to strawberry. Phylogenetic analysis using RAPD marker data divided isolates of C. gloeosporioides from noncultivated hosts into two separate clusters. One cluster contained 50 of the 52 isolates and a second cluster contained 2 isolates that were homothallic in culture. Isolates from strawberry were interspersed within the cluster containing the 50 isolates that were recovered from noncultivated hosts. The results are not inconsistent with the hypothesis that C. gloeosporioides isolates obtained from strawberry and noncultivated hosts adjacent to strawberry fields are from the same population and that noncultivated hosts can serve as potential inoculum sources for Colletotrichum crown rot of strawberry. 相似文献
13.
The first recorded outbreak of anthracnose ( Colletotrichum acutatum ) on ornamental lupin in the United Kingdom occurred in 1989. Seedborne infection by Colletotrichum acutatum was investigated after seed was implicated in the origin of the outbreaks and infection was found on seed of three of 14 cultivars tested. In pathogenicity tests, typical anthracnose symptoms developed only on plants of Lupinus spp; there were slight symptoms on Pisum sativum Vicia sativa and Lathyrus odoratus , but none on Vicia faba, Phaseolus coccineus, P. vulgaris and Onobrychis viciifolia 相似文献
14.
Internal transcribed spacers (ITS) of the ribosomal RNA gene (rDNA) were sequenced for 236 isolates covering 25 Colletotrichum species collected in Japan. The Japanese isolates could be grouped into 20 ribosomal groups (RGs) based on the sequences of
ITS1, correlating the species identified by the morphology. Colletotrichum gloeosporioides sensu lato separated into three RGs that were morphologically different. Colletotrichum destructivum, C. linicola and C. higginsianum were possibly conspecific. Colletotrichum dematium sensu lato including C. capsici and other species that produce falcate conidia except for graminicolous ones were separated into three RGs that were difficult
to distinguish morphologically. In the phylogenetic study using ITS2 and the 28S rDNA domain 2 region, topologies compiled
by neighbor-joining and maximum-parsimony methods were almost the same, reflecting the conidial morphology. The phylogenetic
group 1 (PG1) produced conidia with acute ends, e.g., C. acutatum, C. destructivum and C. graminicola; PG2 produced those with obtuse ends, e.g., C. gloeosporioides, and C. orbiculare. Colletotrichum theae-sinensis, which produced the smallest conidia, was grouped as PG3, far from other species, indicating it should not belong to Colletotrichum. Grouping and phylogenetic analysis using ribosomal DNA was an effective tool to classify and identify Colletotrichum species without using morphology.
Received 15 July 2002/ Accepted in revised form 12 November 2002 相似文献
15.
ABSTRACT Isolates of Colletotrichum spp. from diseased strawberry fruit and crowns were evaluated to determine their genetic diversity and the etiology of the diseases. Isolates were identified to species using polymerase chain reaction primers for a ribosomal internal transcribed spacer region and their pathogenicity was evaluated in bioassays. Isolates were scored for variation at 40 putative genetic loci with random amplified polymorphic DNA and microsatellite markers. Only C. acutatum was recovered from diseased fruit. Nearly all isolates from crowns were C. gloeosporioides. In crown bioassays, only isolates of C. gloeosporioides from strawberry caused collapse and death of plants. A dendrogram generated from the genetic analysis identified several primary lineages. One lineage included isolates of C. acutatum from fruit and was characterized by low diversity. Another lineage included isolates of C. gloeosporioides from crowns and was highly polymorphic. The isolates from strawberry formed distinctive clusters separate from citrus isolates. Evaluation of linkage disequilibrium among polymorphic loci in isolates of C. gloeosporioides from crowns revealed a low level of disequilibrium as would be expected in sexually recombining populations. These results suggest that epidemics of crown rot are caused by Glomerella cingulata (anamorph C. gloeosporioides) and that epidemics of fruit rot are caused by C. acutatum. 相似文献
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云南葡萄产区葡萄炭疽病病原鉴定及致病力分析 总被引：11，自引：6，他引：5
为了明确引起云南葡萄产区炭疽病的病原种类,利用形态鉴定和特异性引物分子检测相结合的方法对从云南省主要葡萄产区采集的60株炭疽病菌菌株进行了鉴定。葡萄炭疽病菌菌株的菌落形态和生长速率与对照菌株尖孢炭疽菌Colletotrichum acutatum差异不明显,但其分生孢子大小显著小于尖孢炭疽菌,附着胞深褐色,球形或不规则形。胶孢炭疽菌Colletotrichum gloeosporioides特异性引物CgInt/ITS4从供试葡萄炭疽病菌菌株基因组DNA中扩增出1条约500 bp的特异性条带,而尖孢炭疽菌特异性引物CaInt2/ITS4对葡萄炭疽病菌无扩增条带。研究表明,引起云南葡萄主产区炭疽病的病原为胶孢炭疽菌;供试胶孢炭疽菌对红提葡萄均有致病力,但菌株致病力差异较大,对番茄和草莓存在交叉侵染的能力,且对多菌灵的敏感性较尖孢炭疽菌高。 相似文献
19.
E.E. Kuramae-Izioka C.R. Lopes N.L. Souza M.A. Machado 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(4):323-329
Brazilian isolates of Colletotrichum spp. from citrus orchards affected by postbloom fruit drop were examined for colony colour, mycelial growth, benomyl-resistance, pathogenicity, and genetic variability by random amplified polymorphic DNA (RAPD) analysis. All isolates were obtained from flowers and persistent calyxes from different citrus hosts from Sao Paulo, Brazil. DNA polymorphisms detected after amplification with random 10-mer primers were used to classify the isolates into two groups. Group I isolates grew rapidly on potato-dextrose agar (PDA) and were sensitive to benomyl, and group II isolates grew slowly on PDA and were benomyl-resistant. Colletotrichum acutatum was analyzed by RAPD and had high genetic similarity with group II isolates of Colletotrichum from citrus. Probably, the group I is C. gloeosporioides and group II is C. acutatum. 相似文献
20.
为明确甘肃省枸杞炭疽病菌对甾醇脱甲基抑制剂类药剂 (DMIs) 的敏感性,采用菌丝生长速率法测定了采自甘肃省靖远县3个地区及景泰县3个地区共102株枸杞炭疽病菌对苯醚甲环唑、戊唑醇、丙环唑及氟硅唑的敏感性,分别就不同年份、不同地区间胶孢炭疽复合种和尖孢炭疽复合种对4 种 DMIs 杀菌剂的敏感性差异进行了分析。结果表明:供试46 株枸杞胶孢炭疽复合种整体上对苯醚甲环唑、戊唑醇、丙环唑和氟硅唑仍表现为敏感,EC50值分别在0.28~1.20、0.11~2.98、0.32~2.84和0.35~3.85 μg/mL之间;而56株尖孢炭疽复合种对4种药剂的敏感性则出现了不同程度分化,部分菌株疑似已出现敏感性下降现象,其中,对苯醚甲环唑、戊唑醇、丙环唑和氟硅唑敏感性最低的菌株EC50值分别为1.63、3.80、6.21和4.74 μg/mL。不同年份间采集的枸杞胶孢炭疽复合种和尖孢炭疽复合种对4种杀菌剂的敏感性均存在显著差异,2017年采集的菌株敏感性相对更低,4种杀菌剂对胶孢炭疽复合种的平均EC50值分别为 (0.84 ± 0.03)、(1.23 ± 0.13)、(1.19 ± 0.09) 和 (1.69 ± 0.17) μg/mL,对尖孢炭疽复合种的平均EC50值分别为 (1.06 ± 0.03)、(2.25 ± 0.15)、(2.43 ± 0.20) 和 (2.85 ± 0.19) μg/mL。不同地区枸杞炭疽病菌对4种杀菌剂的敏感性表现不同,其中靖远县五合镇的胶孢炭疽复合种对4种杀菌剂敏感性最低,平均EC50值分别为 (0.79 ± 0.12)、(1.28 ± 0.87)、(1.39 ± 1.05) 和 (1.74 ± 1.04) μg/mL,景泰县草窝滩镇的胶孢炭疽复合种对苯醚甲环唑和丙环唑敏感性最高,平均EC50值为 (0.28 ± 0.10) 和 (0.46 ± 0.10) μg/mL,对戊唑醇和氟硅唑敏感性最高的胶孢炭疽复合种来自景泰县寺滩乡,平均EC50值为 (0.42 ± 0.16) 和 (0.65 ± 0.09) μg/mL;不同地区间采集的尖孢炭疽复合种对4种杀菌剂的敏感性则不存在显著差异。研究结果可为甘肃省枸杞炭疽病防治中杀菌剂的合理使用及延缓抗药性发展提供依据。 相似文献