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1.
Three hundred and eighteen Colletotrichum gloeosporioides isolates from stem-end rot and anthracnose infected avocados as well as from stem-end rot/anthracnose and soft brown rot on mango, were compared using fruit inoculations. Isolates could be categorised according to lesion size and both avocado and mango isolates produced larger lesions when inoculated on their own hosts. Cross-inoculation potential of these isolates was also compared on strawberries, peppers, guavas, papayas and citrus. All isolates produced lesions on all hosts except citrus. Factors such as area of origin and symptom type from which original isolations were made, could not be correlated with lesion development on these hosts. 相似文献
2.
Sang Ho Park Chang Won Choi Myoung Yong Shim Won Mok Park Soon Seop Hwang Jung-Mo Koo 《Biotechnology letters》2001,23(20):1719-1722
The fungus, Colletotrichum gloeosporioides, which is pathogenic to peppers produced an extracellular polysaccharide in liquid culture which possessed clay-dispersing activity. The polysaccharide could bind cationic dyes, Ruthenium Red and Alcian Blue, indicating it to be polyanionic. The polysaccharide dispersed kaolin in water and the dispersion was maintained for more than 7 days at 25 °C. Kaolin dispersion by the polysaccharide was stable from pH 3 to 10 but the addition of divalent metals at 1 mM inhibited half of the dispersion activity comparing to the control. The polysaccharide could disperse bentonite, calcium carbonate and other fine particles but did not possess emulsifying activity. 相似文献
3.
Tapia-Tussell R Quijano-Ramayo A Cortes-Velazquez A Lappe P Larque-Saavedra A Perez-Brito D 《Molecular biotechnology》2008,40(3):293-298
Colletotrichum gloeosporioides is the common causal agent of anthracnose in papaya (Carica papaya L.) fruits, and infection by this fungal pathogen results in severe post-harvest losses. In the Yucatán peninsula (Mexico)
a different Colletotrichum species was isolated from papaya fruits with atypical anthracnose lesions. The DNAs from a variety of Colletotrichum isolates producing typical and atypical lesions, respectively, were amplified by PCR with C.gloeosporioides-specific primers. All isolates from typical anthracnose lesions yielded a 450 bp PCR product, but DNAs from isolates with
atypical lesions failed to produce an amplification product. For further characterization, the rDNA 5.8S-ITS region was amplified
by PCR and processed for sequencing and RFLP analysis, respectively, to verify the identity of the papaya anthracnose pathogens.
The results revealed unequivocally the existence of two Colletotrichum species causing anthracnose lesions on papaya fruits: C. gloeosporioides and C. capsici. PCR-RFLP using the restriction endonuclease MspI reliably reproduced restriction patterns specific for C. capsici or C. gloeosporioides. The generation of RFLP patterns by MspI (or AluI or RsaI) is a rapid, accurate, and unequivocal method for the detection and differentiation of these two Colletotrichum species. 相似文献
4.
S. Jayasankar Richard E. Litz Dennis J. Gray Pamela A. Moon 《In vitro cellular & developmental biology. Plant》1999,35(6):475-479
Summary
Colletotrichum gloeosporioides Penz., the causal agent of mango anthracnose, produces a phytotoxin in vitro. The partially purified phytotoxin, presumably
colletotrichin, caused anthracnose-like symptoms on young mango leaves, was toxic to embryogenic suspension cultures of two
mango cultivars, ‘Hindi’ and ‘Carabao,’ and inhibited in vitro seed germination of two nonhosts, lettuce and tobacco. There
were linear relationships between concentration of the partially purified phytotoxin and mortality of mango embryogenic cultures.
Embryogenic cultures grown in the presence of the partially purified phytotoxin showed significantly lower growth rates than
the controls. Similarly, embryogenic cultures grown in the presence of 40% (vol/vol) fungal culture filtrate showed significantly
lower growth rates than unchallenged controls. Medium containing 40% (vol/vol) Czapek-Dox fungal broth did not reduce growth
of embryogenic cultures, indicating the production of phytotoxin in vitro. The results suggest that either fungal culture
filtrate or purified phytotoxin can be used as in vitro selection agents to screen for resistance to this fungus. 相似文献
5.
Theobroma cacao L. plants over-expressing a cacao class I chitinase gene (TcChi1) under the control of a modified CaMV-35S promoter were obtained by Agrobacterium-mediated transformation of somatic embryo cotyledons. Southern blot analysis confirmed insertion of the transgene in eight independent lines. High levels of TcChi1 transgene expression in the transgenic lines were confirmed by northern blot analysis. Chitinase activity levels were measured using an in vitro fluorometric assay. The transgene was expressed at varying levels in the different transgenic lines with up to a sixfold increase of endochitinase activity compared to non-transgenic and transgenic control plants. The in vivo antifungal activity of the transgene against the foliar pathogen Colletotrichum gloeosporioides was evaluated using a cacao leaf disk bioassay. The assay demonstrated that the TcChi1 transgenic cacao leaves significantly inhibited the growth of the fungus and the development of leaf necrosis compared to controls when leaves were wound inoculated with 5,000 spores. These results demonstrate for the first time the utility of the cacao transformation system as a tool for gene functional analysis and the potential utility of the cacao chitinase gene for increasing fungal pathogen resistance in cacao. 相似文献
6.
Colletotrichum acutatum is the main cause of Colletotrichum leaf disease of rubber in Sri Lanka 总被引:1,自引:0,他引:1
Colletotrichum gloeosporoides has been described as the causal agent of Colletotrichum leaf disease of rubber in Sri Lanka and other parts of the world since 1905. A study carried out on vegetative and reproductive characteristics of 52 isolates from Colletotrichum leaf disease lesions on Hevea brasiliensis in Sri Lanka revealed that only 18 isolates belong to Colletotrichum gloeosporioides. The remaining 34 isolates represented C. aculatum indicating that C. acutatum is the main cause of Colletotrichum leaf disease in Sri Lanka.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
7.
Fifty-three cassava lines were selected from breeding populations at the International Institute of Tropical Agriculture (IITA),
Ibadan, Nigeria and screened in vitro for resistance to cassava anthracnose disease (CAD). The in vitro inoculation of stem
cuttings with the fungus Colletotrichum gloeosporioides f.sp. manihotis showed significant differences (p ± 0.05) in acervuli production and in the sensitivity of the cassava lines to the fungal
infection after 7 days of incubation at 25 °C. Cassava lines 88/01084, 91/00595, 91/00475, 91/00344, 91/00684, 91/00313, 91/00422,
and 91/00344 were highly resistant, with necrotic lesion sizes less than 7 mm. In contrast pedigree lines 88/02549, 89/0008,
91/00390 and 91/00402 were highly susceptible with the largest necrotic lesion size being greater than 20 mm. Ten cassava
lines from the in vitro screening that showed varying levels of resistance to CAD were selected, based on their flowering
abilities for diallel hydridization trials, and were further screened in greenhouse and field trials for CAD resistance. The
greenhouse and field screening showed significant varietal differences (p ± 0.05) in sensitivity to the fungus. In all cases,
the progeny lines showed correlated levels of resistance irrespective of the type of screening or assessments. Correlation
analysis of the in vitro, greenhouse and field assessments showed that there was a good correspondence among all three methods
of evaluating for CAD.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
8.
Colletotrichum kahawae is the causal agent of coffee berry disease. Appressorial melanization is essential for the fungal penetration of plant cuticle. Epicatechin is abundant in green coffee berry pericarp. Inoculation of C. kahawae conidial suspension containing 1.2 mg epicatechin or catechin/ml did not affect conidial germination or appressorial formation but appressorial melanization was completely inhibited and infection by the treated conidia was less than 30% of the untreated control. Epicatechin and catechin may, therefore, prevent coffee berry disease by inhibition of the appressorial melanization of C. kahawae. 相似文献
9.
Jo?o Frederico M. dos Passos Pedro B. da Costa Murilo D. Costa Gilmar R. Zaffari Gilberto Nava José Itamar Boneti Andréia Mara R. de Oliveira Luciane M.P. Passaglia 《Genetics and molecular biology》2014,37(3):560-572
This study evaluated the diversity of cultivable plant growth-promoting (PGP) bacteria associated with apple trees cultivated under different crop management systems and their antagonistic ability against Colletotrichum gloeosporioides. Samples of roots and rhizospheric soil from apple trees cultivated in organic and conventional orchards in southern Brazil were collected, together with soil samples from an area never used for agriculture (native field). Bacteria were identified at the genus level by PCR-RFLP and partial sequencing of the 16S rRNA, and were evaluated for some PGP abilities. The most abundant bacterial genera identified were Enterobacter (27.7%), Pseudomonas (18.7%), Burkholderia (13.7%), and Rahnella (12.3%). Sixty-nine isolates presented some antagonist activity against C. gloeosporioides. In a greenhouse experiment, five days after exposure to C. gloeosporioides, an average of 30% of the leaf area of plants inoculated with isolate 89 (identified as Burkholderia sp.) were infected, whereas 60 to 73% of the leaf area of untreated plants was affected by fungal attack. Our results allowed us to infer how anthropogenic activity is affecting the bacterial communities in soil associated with apple tree crop systems, and to obtain an isolate that was able to delay the emergence of an important disease for this culture. 相似文献
10.
Chen Z Franco CF Baptista RP Cabral JM Coelho AV Rodrigues CJ Melo EP 《Applied microbiology and biotechnology》2007,73(6):1306-1313
Colletotrichum kahawae is the causal agent of the coffee berry disease, infecting leaves and coffee berries at any stage of their development. Colletotrichum gloeosporioides is the causal agent of brown blight, infecting ripe berries only. Both fungi secrete the same pattern of carboxylesterases
to the fermentation broth when cutin is used as carbon source. By using two different strategies composed of two precipitation
steps (ammonium sulphate and acetic acid precipitation) and two chromatographic steps, two proteins displaying carboxylesterase
activity were purified to electrophoretic homogeneity. One, with a molecular weight (MW) of 21 kDa, has a blocked N terminus
and was identified as cutinase by peptide mass fingerprint and mass spectrometry/mass spectrometry data acquired after peptide
derivatization with 4-sulphophenyl isothiocyanate. The second, with a MW of 40 kDa, displays significant carboxylesterase
activity on tributyrin but low activity on p-nitrophenyl butyrate. N-terminal sequencing for this protein does not reveal any homology to other carboxylesterases. These
two enzymes, which were secreted by both fungi, appear homologous. 相似文献
11.
Changes in phenolic metabolism after elicitation with Colletotrichum gloeosporioides (CG) has been studied in Hypericum perforatum L. (HP) cell suspension cultures. Soluble phenolics were analysed by HPLC-DAD and HPLC-DAD-MS/MS. HP cultures elicited with the CG elicitor showed a significant increase in xanthone accumulation. Xanthone accumulation increased twelve fold when the cells were primed with methyl-jasmonate (MeJ) or salicylic acid (SA), before elicitation. HP cultures exposed only to MeJ produced a set of flavonoids, the flavones which represent a substantial part (approx. 40%) of the total flavonoids accumulated in these cells. The possible importance of xanthones as a component of defence mechanism of HP against biotic stress is discussed. 相似文献
12.
Colletotrichum gloeosporioides is a weak pathogen of coffee that infects ripe berries at dark red stage causing necrotic lesions, but only penetrates up to the second superficial layers of the pericarp at the rose and pink stages. C. kahawae, the causal agent of coffee berry disease (CBD) and responsible for 70–80% of crop loss, infects berries at any stage of development. When green berries are first inoculated with C. kahawae and then at 2, 72 or 96 h later with C. gloeosporioides, the necrotic lesions were significantly larger than in the controls, and were much more evident when the berries were incubated at the optimum growth temperature of 28 °C for C. gloeosporioides. Isolations from the lesions induced by the first inoculations with C. kahawae followed by inoculation with C. gloeosporioides revealed that all or most of the time the recovered isolates of the latter. Thus, C. gloeosporioides can overwhelm C. kahawae under conditions of higher environmental temperature and humidity and may enhance the CBD infection process under field conditions. 相似文献
13.
Colletotrichum acutatum has become an increasingly important plant pathogen worldwide. With this background, a study was carried out to characterize
the toxicity of liquid culture media from different isolates and to identify some properties of the toxic principles. Liquid
culture media from all isolates were toxic to rubber leaves and induced the anthracnose symptoms. Toxicity of the culture
filtrate was not host specific and toxic substances were thermostable. Acetone soluble fraction of the culture filtrates retained
the toxic activity and it was effective even at a concentration of 700 μg dry mycelium mass/ml.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
14.
We have investigated the production of proteinase and phospholipase by 20 different isolates of Paracoccidioides brasiliensis. Isolates were grown in Bacto-peptone, Dextrose, pH 5.5, agar slants, at 27 °C for 30 days, and cultures were transferred
onto Petri dishes containing basis medium and bovine serum albumin fraction V and sterile egg yolk as substrates for enzyme
production, and incubated at 27 °C. After 30 days net enzyme activity was visualized and quantitavely evaluated, measuring
a ratio between colony diameter and diameter of the transparent (proteinase) or white (phospholipase) ring zone surrounding
it. Results demonstrated that all isolates had the ability to produce proteinase and phospholipase, even though variability
in enzyme production was noted among different isolates of P. brasiliensis.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
15.
An exocellular proteinase synthesized by the geophilic dermatophyte Trichophyton vanbreuseghemii has been purified and characterized. The fungus obtained from soil in Iran was cultivated in modified Czapek–Dox liquid medium
containing 0.1% bacteriological peptone and 1% glucose as the nitrogen and carbon sources. Partial purification of the proteinase
was accomplished by (NH4)2SO4 precipitation, followed by ion exchange chromatography. Analysis of the enzyme by SDS-PAGE revealed a single polypeptide
chain with an apparent molecular mass of 37 kDa. Proteinase activity was optimum at pH 8, but remained high in the range of
pH 7–11. Moreover, the partially purified enzyme presented a keratinolytic activity as evidenced by the keratin azure test.
The inhibition profile and the good activity of the enzyme towards the synthetic substrate N-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide suggested that it belonged to the chymotrypsin/subtilisin group of serine proteinases. The keratinolytic properties
of T. vanbreuseghemii suggest that this fungus may be an alternative for the recycling of industrial keratinic wastes. 相似文献
16.
Sequence of the gene encoding an alkaline serine proteinase of Bacillus pumilus TYO-67 总被引:3,自引:0,他引:3
The complete nucleotide sequence of the gene encoding an alkaline serine proteinase (aprP) of Bacillus pumilus TYO-67 was determined. The sequence analysis showed an open reading frame of 1,149 bp (383 amino acids) that encoded a signal peptide consisting of 29 residues and a propeptide of 79 residues. The deduced 3 amino acid residues, D32, H64, and S221, were identical with 3 essential amino acids in the catalytic center of subtilases. The sequence around these residues revealed that APRP was a new member of the true subtilisin subgroup of the subtilisin family. The highest homology was found in subtilisin NAT at 64.4% in the DNA sequence. The residue S189 of APRP was different from those of other subtilases. 相似文献
17.
A. R. Kayumov N. P. Balaban A. M. Mardanova S. V. Kostrov M. R. Sharipova 《Microbiology》2006,75(5):557-562
The biosynthesis of the subtilisin-like serine proteinase of Bacillus intermedius 3–19 by the recombinant strain Bacillus subtilis AJ73(pCS9) was found to be enhanced under salt stress conditions (growth in a medium containing 1 MNaCl and 0.25 M sodium citrate). In a recombinant strain of B. subtilis deficient in the regulatory proteins DegS and DegU, which control the synthesis of degradative enzymes, the expression of the proteinase gene was inhibited. In contrast, in the strain B. subtilis degU32(Hy), which provides for the overproduction of proteins positively regulated by the DegS-DegU system, the biosynthesis of the subtilisin-like proteinase of B. intermedius 3–19 increased by 6–10 fold. These data suggest that the DegS-DegU system is involved in the positive regulation of the expression of the subtilisin-like B. intermedius proteinase gene in recombinant B. subtilis strains. 相似文献
18.
Fruit anthracnose of ugurassa caused by Colletotrichum acutatum is hereby reported for the first time in Sri Lanka and it is proposed that C. acutatum is considered together with C. gloeosporioides, as a causal agent of this disease. C. acutatum was characterised by fusiform conidia and white to orange colonies with slight shades of light mouse grey aerial mycelia. C. gloeosporioides produced grey colonies with a dark mouse grey centre and conidia were cylindrical. The other differences between the ugurassa isolate of C. acutatum and C. gloeosporioides were slower growth at temperatures ranging from 15-30 degrees C and extremely high tolerance of two fungicides, carbendazim and thiophanate methyl. 相似文献
19.
蓝光诱导的胶孢炭疽菌(Colletotrichum gloeosporioides)类胡萝卜素积累 总被引:1,自引:0,他引:1
胶孢炭疽菌(Colletotrichumgloeosporioides)为一种丝状真菌,蓝光照射可诱导类胡萝卜素的积累。光镜下观察表明,蓝光可诱导胶孢炭疽菌菌丝积累色素颗粒,而黑暗和红光处理却无此现象。类胡萝卜素的积累受蓝光光照强度的影响。28℃且蓝光为6.5μmol.m-2.s-1时,类胡萝卜素积累量可随光照时间延长呈增长趋势,在第5天达到最高峰为71.8μg/g FW,随后含量下降。此外,胶孢炭疽菌在黑暗中预培养的时间也影响蓝光的诱导反应。 相似文献
20.
Kotlova EK Ivanova NM Yusupova MP Voyushina TL Ivanushkina NE Chestukhina GG 《Biochemistry. Biokhimii?a》2007,72(1):117-123
An extracellular thiol-dependent serine proteinase was isolated from culture medium filtrate of the microscopic fungus Paecilomyces lilacinus with a yield of 33%. The enzyme is inactivated by specific inhibitors of serine proteinases, phenylmethylsulfonyl fluoride, as well as by chloromercuribenzoate and mercury acetate, but is resistant to chelating agents. The proteinase has broad specificity, hydrolyzes proteins and p-nitroanilides of N-acylated tripeptides, exhibiting maximal activity in hydrolysis of substrates containing long hydrophobic and aromatic residues (norleucine, leucine, phenylalanine) as well as arginine at the P1 position. The enzyme has a molecular weight of 33 kD. The enzyme is most active at pH 10.0-11.5; it is thermostable and is characterized by broad optimum temperature range (30-60 degrees C), displaying about 25% of maximal activity at 0 degrees C. The N-terminal sequence of the enzyme (Gly-Ala-Thr-Thr-Gln-Gly-Ala-Thr-Gly/Ile-Xxx-Gly) has no distinct homology with known primary structures of serine proteinases from fungi and bacilli. Based on its physicochemical and enzymatic properties, the serine proteinase from P. lilacinus can be classified as a thiol-dependent subtilisin-like enzyme. 相似文献