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Seed-borne fungi cause several diseases of common bean (Phaseolus vulgaris L.) and soybean (Glycine max L.). The survey of seed-borne fungi of common bean and soybean was carried out on three Egyptian Governorates (Behera, Dakahlia, and Ismailia) in Egypt. Nineteen fungal species comprising therteen genera were isolated from the collected common bean and soybean seed samples, using standard blotter i,e. Alternaria alternata, Alternaria spp., Aspergillus niger, Aspergillus ochraceous, Aspergillus flavus, Botryodiplodia sp., Cladosporium sp., Colletotrichum lindemuthianum, Colletotrichum dematium, Fusarium solani, Fusarium moniliforme, Fusarum oxysporum, Macrophomina phaseolina, Myrothecium sp., Penicillium spp, Rhizoctonia solani, Stemphylium spp., Trichoderma spp. and Trichothecium sp. Pathogenicity tests proved that C. lindemuthianum and C. dematium were pathogenic to common bean and soybean. Polymerase chain reaction (PCR) has many beneficial characteristics that make it highly applicable for detecting Colletotrichum spp. of seeds. PCR diagnosis method and DNA extraction considered one of the most important steps and purity of DNA template for successful PCR assay. For the PCR amplification of C. lindemuthianum and C. dematium, two primers ClF4 and ClF5, stander blotter, agar plate, and deep freezing method were used as seed healthy testing methods. Stander blotter was proved the past and quickly method to detect seed-born of C. lindemuthianum and C. dematium. Trichoderma harzianum reduced linear growth for C. lindemuthianum and C. dematium followed by Trichoderma viride and Bacillus subtilis recording (3.3 cm and 3.9 cm, respectively) followed by Pseudomonas floursence that display a high linear growth (7.4 cm). On the other hand, fungicide Aetro 30% (Iprodione + Tebuconazole) recorded the least linear growth (0.9 cm) for C. lindemuthianum and C. dematium compared with negative control recorded (9.0 cm in diameter). Thymus plant extract caused the lowest liner growth (3.7 cm). Plant extract concentrations caused a significant reduction in the growth of C. lindemuthianum and C. dematium. The highest concentration (1.5 %) gave less fungal growth while the lowest one (0.5%) showed the highest fungal growth compared with negative control.

Colletotrichum species are known as important pathogens of plants with an impact on crop production. Some of these species are also known as a cause of rare ophthalmic infections in humans. A case of keratitis caused by Colletotrichum dematium after corneal trauma in a 56-year-old woman is presented. Infection was diagnosed based on positive microscopy and culture. The fungal isolate was identified by morphological characteristics and DNA sequencing of the ITS rDNA region, β-tubulin (tub2) and glyceraldehyde-3-phosphate dehydrogenase (gapdh) genes. The patient responded well to topical therapy with amphotericin B combined with intravenous amphotericin B but improvement was associated with the corneal collagen cross-linking. The review of the literature revealed another 13 cases of C. dematium keratitis, all but one patient having at least one keratitis risk factor in their history. Almost all patients (n = 12) were treated with topical polyene antibiotics (natamycin or amphotericin B), improvement and cure were achieved in eight of them.

In this study, a new species within the genus Colletotrichum was isolated from diseased persimmon leaves collected from Sangju and Cheongdo in the Gyeongbuk province of Korea. The disease was characterized by leaf spots with a brown to gray center surrounded by a black ring with a green halo. Black acervuli with setae and numerous curved conidia were observed on the leaf spots. Phylogenetic analysis based on a combination of multiple loci, including sequences of the internal transcribed spacers, actin, beta-tubulin, chitin synthase-1, and glyceraldehyde-3-phosphate dehydrogenase genes, revealed that the isolates were clearly distinct from other species of the Colletotrichum dematium complex, with the closest species being C. anthrisci. Cultural and morphological characteristics and pathogenicity on persimmon leaves were examined. The isolates differed from C. anthrisci in their cultural and morphological characteristics, such as the conidia and appressoria. Based on molecular phylogenetic, morphological, and cultural characteristics and pathogenicity, this fungus was demonstrated to be a new species, Colletotrichum kakivorum, and the causal agent of a leaf spot disease on persimmon in Korea.

Fungal diseases of cotton plant ( Gossypium hirsutum L.) were studied during July, 2011 to June, 2012. Eleven cotton varieties were selected for the experiment. Alternaria alternata (Fr . ) Keissler, Aspergillus niger van Tiegh, Colletotrichum gossypii Sowthworth, Colletotrichum dematium (Pers.) Grove, Curvularia clavata Jain, Fusarium sp., Gleotrichum sp., Hyalopycnis sp., Pestalotiopsis guepinii (Desm.) Stay, and a sterile fungus were isolated from infected leaves of cotton varieties CB6 and CB11. Colletotrichum gossypii was isolated from both the varieties and C. dematium was exclusively isolated from CB6. Varieties CB6 and CB11 were more susceptible than other varieties. Cotton varieties CB1, CB2, and CB3 showed negligible infection on leaves and bolls. Colletotrichum gossypii and Hyalopycnis sp. are new record for Bangladesh. Moreover, association of C. dematium, Gleotrichum sp. , P. guepinii and Hyalopycnis sp. with cotton is being reported first time. The three fungi Colletotrichum. gossypii, C. dematium and Hyalopycnis sp. are described and illustrated in this account as new Deuteromycetous records for Bangladesh. Journal of Bangladesh Academy of Sciences, Vol. 39, No. 2, 213-221, 2015

Ninety fungal strains with falcate conidia belonging to Colletotrichum spp. classified into the ribosomal groups 9-13 (the RG 9-13 spp.) and preserved at the NIAS Genebank, Japan were re-identified based on molecular phylogenetic analysis of the internal transcribed spacer (ITS) region of the rRNA gene, sequences of the glyceraldehyde 3-phosphate dehydrogenase, chitin synthase 1, histone3, and actin genes, and partial sequences of β-tubulin-2 (TUB2) genes, or by BLASTN searches with TUB2 gene sequences. Seventy strains were reclassified into nine recently revised species, C. chlorophyti, C. circinans, C. dematium sensu stricto, C. lineola, C. liriopes, C. spaethianum, C. tofieldiae, C. trichellum and C. truncatum, whereas 20 strains were grouped into four unidentified species. RG 9, 10 and 12 corresponded to the C. spaethianum, C. dematium and C. truncatum species complex, respectively, while RG 11 and 13 agreed with C. chlorophyti and C. trichellum, respectively. Phylograms derived from a six-locus analysis and from TUB2 single-locus analysis were very similar to one another with the exception of the association between C. dematium s. str. and C. lineola. Thus, TUB2 partial gene sequences are proposed as an effective genetic marker to differentiate species of RG 9-13 in Japan except for C. dematium s. str. and C. lineola. Thirty-two plant species were identified as new hosts for seven of the species found in this study except for C. circinans and C. trichellum; and two unidentified species. Colletotrichum chlorophyti, C. lineola, C. liriopes, C. spaethianum, and C. truncatum were regarded as polyphagous, whereas C. trichellum and Colletotrichum sp. (Ra), designated tentatively in this study, appeared to have specific pathogenicity to single hosts, Hedera rhombea and Raphanus sativus var. hortensis, respectively. Conidial curvature properties, "outer curvature," "inner curvature" and "height/width ratio" successfully represented conidial shape parameters. Conidial curvature properties of the species in RG 9, 10 and 12 were found to correlate with the species complexes. Discipline: Agricultural Environment Additional key words: β-tubulin-2, conidial curvature properties, molecular phylogenetic analyses, re-identification, species complex This paper reports results obtained in the NIAS Genebank project sponsored by the Ministry of Agriculture, Forestry and Fisheries, Japan. *Corresponding author: e-mail s1043@affrc.go.jp Received 24 October, accepted 3 April 2015. Introduction The genus Vermicularia Tode (1790) was established for anthracnose fungi with falcate conidia and setae in acervuli. More than 280 species have been described with nearly every host plant identified (Anonymous 2014). More species with falcate conidia were also described as species in Colletotrichum Corda (1831). Since Arx (1957) synonymized many Vermicularia as well as Colletotrichum species with Colletotrichum graminicola (Ces.) G.W. Wilson and Colletotrichum dematium (Pers.) Grove in addition to its three forma based on morphology, C. graminicola and C. dematium have been regarded as representatives of pathogens on the Poales grasses and other plants, respectively (Arx 1981, 1987, Sutton 1980, 1992). More than 230 strains of Colletotrichum in Japan, including those with falcate conidia and setae, were classified into 20 ribosomal groups (RG) based on molecular phylogenetic analyses of the

The metabolism of the phytoalexin rapalexin A, a unique indole isothiocyanate (ITC) produced by crucifers (family Brassicaceae), was investigated. Three phytopathogenic fungal species were examined: Colletotrichum dematium (Pers.:Fr.) Grove, a broad host range pathogen, C. higginsianum Sacc., a host-selective pathogen of crucifers and C. lentis Damm, a host-selective pathogen of lentils (Lens culinaris Medik.). The metabolism of rapalexin A by C. dematium and C. higginsianum was similar, taking place via one common intermediate and two divergent pathways, but C. lentis was unable to transform rapalexin A. Both C. higginsianum and C. dematium transformed rapalexin A to two previously undescribed metabolites, the structures of which were confirmed by chemical synthesis: N-acetyl-S-(8-methoxy-4H-thiazolo[5,4-b]indol-2-yl)-L-cysteine and 4-hydroxy-3-(4-methoxy-1H-indol-3-yl)-2-thioxothiazolidine-4-carboxylic acid. That is, both fungal pathogens metabolized and detoxified rapalexin A by addition of the thiol group of L-Cys residue to the isothiocyanate carbon of rapalexin A, a transformation usually catalyzed by glutathione transferases. Coincidentally, this metabolic pathway is employed by mammals and insects to detoxify isothiocyanates and other xenobiotics. Hence, C. higginsianum could be a useful model fungus to uncover genes involved in the detoxification pathways of ITCs and related xenobiotics. Our overall results suggest that increasing rapalexin A production in specific crucifers could increase crop resistance to certain fungal pathogens.

Paclitaxel (taxol) has long been used as a potent anticancer agent for the treatment of many cancers. Ever since the fungal species Taxomyces andreanae was first shown to produce taxol in 1993, many endophytic fungal species have been recognized as taxol accumulators. In this study, we analyzed the taxol-producing capacity of different Colletotrichum spp. to determine the distribution of a taxol biosynthetic gene within this genus. Distribution of the taxadiene synthase (TS) gene, which cyclizes geranylgeranyl diphosphate to produce taxadiene, was analyzed in 12 Colletotrichum spp., of which 8 were found to contain the unique skeletal core structure of paclitaxel. However, distribution of the gene was not limited to closely related species. The production of taxol by Colletotrichum dematium, which causes pepper anthracnose, depended on the method in which the fungus was stored, with the highest production being in samples stored under mineral oil. Based on its distribution among Colletotrichum spp., the TS gene was either integrated into or deleted from the bacterial genome in a species-specific manner. In addition to their taxol-producing capacity, the simple genome structure and easy gene manipulation of these endophytic fungal species make them valuable resources for identifying genes in the taxol biosynthetic pathway.

SUMMARYThe aim of the present investigation was to evaluate the antifungal activities of plant extracts which can be used to control bean and cowpea anthracnose. Acetone, ethyl acetate and water extracts of Ipomoea batatas, Carica papaya, Allium sativum, Syzygium cordatum, Chlorophytum comosum and Agapanthus caulescens were screened in vitro for their antifungal activities against Colletotrichum lindemuthianum and Colletotrichum dematium of common bean and cowpea using the agar disc infusion and microtitre double-dilution techniques. The same extracts were then tested for antifungal activity in vivo as seed treatments against anthracnose disease. The water extracts of Carica and Syzygium were active against C. lindemuthianum and had minimum inhibitory concentrations (MICs) of 1·56 mg/ml. Syzygium, Allium and Chlorophytum water extracts were active against C. dematium and MICs were 3·13, 6·25 and 12·5 mg/ml, respectively. The MICs of Allium, Syzygium and Agapanthus acetone extracts were 0·78, 3·13 and 6·25 mg/ml, respectively, against C. lindemuthianum and 0·78, 6·25 and 3·13 mg/ml against C. dematium. Agapanthus water extracts and all the acetone extracts tested in vivo effectively reduced the incidence and severity of bean anthracnose disease in the greenhouse. Agapanthus acetone, Allium water, and both acetone and water extracts of Carica and Syzygium performed well in vivo in reducing cowpea anthracnose disease and compared well with reductions due to the application of the synthetic fungicide fludioxonil+mefenoxam (the commercial product Celest® XL) applied at 25 gai/l and also with levels in the non-inoculated control. The Agapanthus, Carica, Syzygium and Allium extracts were active on both Colletotrichum spp. in vitro and also reduced anthracnose disease of bean and cowpea and are potential seed treatments in anthracnose disease control. The easy seed treatment process and the accessibility of plants used in the present study could lead to high adoption of the use of the plant extracts as seed treatments by resource-poor, smallholder farmers.

Colletotrichum gloeosporioides, Colletotrichum acutatum, Colletotrichum coccodes, and Colletotrichum dematium are the four main species of Colletotrichum that cause tomato anthracnose. In Serbia, the occurrence of anthracnose on tomato fruit has been recorded during the last several years. Typical fruit symptoms include dark, sunken, and circular lesion with orange conidial masses. Pathogen isolates were obtained from a diseased tomato fruits, on PDA medium forming a white to gray colonies. The cultures developed black acervuli around the center of the colony. Conidia were hyaline, aseptate, and fusiform or rarely cylindrical. Appressoria were smooth, simple, clavate to ovate, and varied from light to dark brown. Pathogenicity tests with representative isolates were conducted on symptomless, detached tomato fruits. All tested isolates caused anthracnose lesions on tomato fruit after 7 days of incubation. Koch’s postulates were fulfilled by reisolation from inoculated tomato fruits. PCR analysis (using species-specific primer pair, CaInt2/ ITS4) of genomic DNA from tomato isolates resulted in an amplification product of 490 bp, specific for C. acutatum, further confirming the identity of the pathogen. Based on morphological and molecular characteristics, the isolates from tomato fruit were determined as C. acutatum.

Colletotrichum spp. are casual agents of anthracnose on various economically important crops. To cope with the pitfalls of identifying the fungi by morphotaxonomic criteria, the application of heteroduplex mobility assay (HMA) of internal transcribed spacer (ITS) regions as a biochemical tool was explored. The ITS regions of 29 Colletotrichum isolates including Colletotrichum gloeosporioides, Colletotrichum acutatum, Colletotrichum musae, Colletotrichum graminicola, Colletotrichum capsici, Colletotrichum dematium, Colletotrichum lindemuthianum and three unidentified species of Colletotrichum, were PCR amplified. Comparison of the ITS sequences from 15 Colletotrichum isolates revealed a greater DNA divergence within ITS1 region than that within ITS2. The DNA distance and sequence identity within intra-species ranged from 0.0 to 1.1% and from 98.9 to 100%, respectively; whereas those within inter-species ranged from 1.46 to 13.43% and 90.02 to 98.56%, respectively. From the correlation of DNA distance and relative heteroduplex mobility observed among 15 reference isolates, a formula for estimation of distances of a tested DNA sequence was developed for estimation of DNA distances of a compared strain. The phylogenetic analysis of ITS regions of 29 Colletotrichum isolates using DNA distance inferred from relative heteroduplex mobility divided them into 5 distinctive species groups, namely CG, CA, CC, CM and CL, similar to that assembled based on DNA sequences analysis. Our results show that HMA of ITS regions is a relatively rapid and convenient method for species-specific identification of Colletotrichum spp. The potential use of the established techniques for identification of anthracnose and even other fungal diseases are discussed.

Colletotrichum dematium is an endophytic fungus recovered from a Pteromischum sp. growing in a tropical forest in Costa Rica. This fungus makes a novel peptide antimycotic, colutellin A, with a MIC of 3.6 microg ml(-1) (48 h) against Botrytis cinerea and Sclerotinia sclerotiorum. Collutellin A has a mass of 1127.7 Da and contains residues of Ile, Val, Ser, N-methyl-Val and beta-aminoisobutryic acid in nominal molar ratios of 3 : 2 : 1 : 1 : 1, respectively. Independent lines of evidence suggest that the peptide is cyclic and sequences of Val-Ile-Ser-Ile and Ile-Pro-Val have been deduced by MS/MS as well as Edman degradation methods. Colutellin A inhibited CD4(+) T-cell activation of interleukin 2 (IL-2) production with an IC(50) of 167.3+/-0.38 nM, whereas cyclosporin A in the same test yielded a value of 61.8 nM. Inhibition of IL-2 production by collutellin A at such a low concentration indicates the potential immunosuppressive activity of this compound. In repeated experiments, cyclosporin A at or above 8 microg ml(-1) exhibited high levels of cytotoxicity on human peripheral blood mononuclear cells, whereas collutellin A or DMSO (carrier) alone, after 24 and 48 h of culture, exhibited no toxicity. Because of these properties collutellin A has potential as a novel immunosuppressive drug.

Biological control is an accepted important component of current plant disease management strategies. Introduction of bacterized seeds carrying bacterial isolates with proven growth-promotion capabilities and antagonistic characteristics offer a valid alternative to chemical protectants. Root colonization of disease-susceptible (PS 1024) and moderately resistant (PS1042) varieties of soyabean (Glycine Max L) by fluorescent pseudomonad (FLPs) strains GRP3, PEn-4, PRS1, and WRS-24 was studied in relation to natural occurrence of anthracnose caused by Colletotrichum dematium (Pers Ex Fr.) Grove. Rhizoplane population of FLPs was maintained at a critical level (5.3 cfu) up to 30 days of plant growth, followed by a steep decline. Indigenous FLPs population, however, remained nearly unchanged (3.0 to 2.4 log g(-1) root) between 30 days and 75 days of plant growth. The relative FLPs population in rhizosphere was lower than that in rhizoplane. Although intervarietal difference was observed, the root/shoot length remained unaffected. Compared to nonbacterized control, dry root weight was improved by FLPs treatment. Severity of foliar anthracnose was reduced significantly after FLPs treatment in the variety PS 1042. Because the point of FLPs treatment (seed bacterization) was away from the site of disease appearance (leaf), operation of induced systemic resistance in strains PEn-4 and GRP3 appears imminent.

Colletotrichum dematium is the cause of a new fungal stem disease on cowpea in South Africa. The pre-penetration and infection process of this fungus on cowpea stems was studied by light microscopy and SEM. Conidia began germinating at 6 h post inoculation (hpi), forming appressoria directly or at the ends of germ-tubes. By 14 hpi appressoria had melanized and direct penetration of host tissue had begun. At 20 hpi infection vesicles formed in epidermal cells. Thick, knotted primary hyphae formed from these vesicles and entered adjacent cells. At ‡40 hpi C. dematium produced secondary hyphae which were highly branched, and grew extensively inter- and intracellularly. After approximately 48 hpi light brown lesions appeared on the stem, associated with the invasion of secondary hyphae into cells and cell necrosis. Acervuli with one or two melanized setae were visible on lesions by 70 hpi.

Two cases of fungal keratitis, one caused by Fusarium oxysporum and the other by Colletotrichum dematium, that failed treatment with topical voriconazole 1% are presented. These cases are noteworthy in that topical voriconazole was unable to eradicate the corneal infection in both cases, despite relatively low MIC90 tested for each species of 8 and 1 microg/mL, respectively.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:01:17Z No. of bitstreams: 1 S0103-90162012000100004.pdf: 168537 bytes, checksum: 7331cc1d99b0ee8af55d9f90981f727c (MD5) Made available in DSpace on 2013-08-22T19:01:17Z (GMT). No. of bitstreams: 1 S0103-90162012000100004.pdf: 168537 bytes, checksum: 7331cc1d99b0ee8af55d9f90981f727c (MD5) Previous issue date: 2012-02-01 Made available in DSpace on 2013-09-30T20:01:09Z (GMT). No. of bitstreams: 2 S0103-90162012000100004.pdf: 168537 bytes, checksum: 7331cc1d99b0ee8af55d9f90981f727c (MD5) S0103-90162012000100004.pdf.txt: 37706 bytes, checksum: 1ce4fc7b4394f7533c9a4d960f7fa43a (MD5) Previous issue date: 2012-02-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:16:26Z No. of bitstreams: 2 S0103-90162012000100004.pdf: 168537 bytes, checksum: 7331cc1d99b0ee8af55d9f90981f727c (MD5) S0103-90162012000100004.pdf.txt: 37706 bytes, checksum: 1ce4fc7b4394f7533c9a4d960f7fa43a (MD5) Made available in DSpace on 2014-05-20T13:16:26Z (GMT). No. of bitstreams: 2 S0103-90162012000100004.pdf: 168537 bytes, checksum: 7331cc1d99b0ee8af55d9f90981f727c (MD5) S0103-90162012000100004.pdf.txt: 37706 bytes, checksum: 1ce4fc7b4394f7533c9a4d960f7fa43a (MD5) Previous issue date: 2012-02-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Adequate procedures to evaluate seed vigor are important. Regarding the electrical conductivity test (EC), the interference in the test results caused by seed-borne pathogens has not been clarified. This research was carried out to study the influence of Phomopsis sojae (Leh.) and Colletotrichum dematium (Pers. ex Fr.) Grove var. truncata (Schw.) Arx. fungi on EC results. Soybean seeds (Glycine max L.) were inoculated with those fungi using potato, agar and dextrose (PDA) medium with manitol (-1.0 MPa) and incubated for 20 h at 25 °C. The colony diameter, index of mycelial growth, seed water content, occurrence of seed-borne pathogens, physiological potential of the seeds, measured by germination and vigor tests (seed germination index, cold test, accelerated aging and electrical conductivity), and seedling field emergence were determined. The contents of K+, Ca2+, and Mg2+ in the seed and in the soaking solution were also determined. A complete 2 × 4 factorial design with two seed sizes (5.5 and 6.5 mm) and four treatments (control, seeds incubated without fungi, seeds incubated with Phomopsis and seeds incubated with Colletotrichum) were used with eight (5.5 mm large seeds) and six (6.5 mm large seeds) replications. All seeds submitted to PDA medium had their germination reduced in comparison to the control seeds. This reduction was also observed when seed vigor and leached ions were considered. The presence of Phomopsis sojae fungus in soybean seed samples submitted to the EC test may be the cause of misleading results. UNESP FCAV Depto. de Produção Vegetal UNESP FCAV Depto. de Fitossanidade UNESP FCAV Depto. de Produção Vegetal UNESP FCAV Depto. de Fitossanidade

Two novel triterpenoid glycosides have been isolated from butanolic seeds extract of two varieties of Lathyrus plants, i.e. Lathyrus ratan and Lathyrus aphaca. Their structures were elucidated as 3-O-[β-D-glucuronopyranosyl-(1 → 4)-α-L-arabinopyranosyl-(1 → 2)-α-L-arabinopyranosyl]-olean-11,13(18)-dien-28-oic acid (1) and 3-O-{β-D-xylopyranosyl-(1 → 2)-β-D-glcopyranosyl-(1 → 4)-[β-D-glucopyranosyl-(1 → 2)]-β-D-xylopyranosyl}-2,16α-dihydroxy-4-hydroxymethyl urs-12-en-28-oic acid (2) on the basis of spectral evidences, i.e. FTIR, (1)H-NMR, (13)C-NMR, ESI-MS and FAB-MS data. The isolated saponins were tested for their antifungal activity. Compound 1 showed maximum inhibition against Colletotrichum dematium (77.8%), whereas compound 2 showed maximum inhibition against Alternaria alternata (53.9%).

Five species of Colletotrichum are recognized on Xanthium. Examination of the type and other collections, and cultural studies, show that the common anthracnose fungus on X. spinosum in eastern Australia is C. orbiculare, the cucurbit anthracnose organism. Other hosts of C. orbiculare include some cvs of safflower (Carthamus tinctorius) and other genera of Asteraceae and Apiaceae. On X. occidentale in Queensland and New South Wales, C. acutatum occurs commonly on stem lesions in close association with the rust Puccinia xanthii. Study of the type collection of C. xanthii, described from the United States of America in 1892, has shown it to be identical to C. acutatum. Telia of Puccinia xanthii were also present in the American collection. Colletotrichum dematium has been found on stem and cotyledon lesions of X. occidentale and C. coccodes has been isolated once from cotyledon spots on the same host. In the United States, isolates of C. truncatum pathogenic to soybean (Glycine max) have been reported from field-infected Xanthium spp. These findings are discussed in the light of various taxonomic and nomenclatural problems in Colletotrichum, including (i) species concepts, particularly in C. gloeosporioides sensu lato, (ii) the value of host range as a taxonomic character, (iii) the nomenclature of C. acutatum, and (iv) concealment of information in synonym lists.

Objetivou-se neste trabalho, acompanhar pela microscopia eletrônica de varredura, os processos de infecção, colonização e reprodução de diferentes isolados de Colletotrichum spp. em plântulas de cafeeiro. Plântulas da cultivar Rubi produzidas por cultura de embrião foram inoculadas com 5µL de suspensão de esporos ajustada para 10(6) conídios mL-1, na região do hipocótilo e folhas, após ferimento com agulha entomológica. Os isolados avaliados foram Colletotrichum gloeosporioides (IH), obtido de ramos e (IF) de folhas de planta de café com sintomas de mancha manteigosa, C. dematium (ID) de cafeeiro sadio e C. gloeosporioides (IM) de casca de manga com sintomas de antracnose. Duas horas após as inoculações (HAI), fragmentos de folhas e hipocótilos foram transferidos para microtubos de 1,5mL contendo solução fixadora de Karnovsky modificado. As demais amostras foram coletadas 3, 5, 12, 16, 24, 48, 72, 96, 114 e 144 HAI. Os conídios de todos os isolados aderiram preferencialmente nas depressões dos órgãos inoculados, formando um septo e germinando cinco HAI (C. gloeosporioides) e doze HAI (C. dematium) emitindo tubos germinativos, tanto nas extremidades como lateralmente. Apressórios globosos, trilobulados, em forma de pé e de vírgula foram produzidos apenas por C. dematium (ID), 12 HAI; enquanto que C. gloeosporioides (IF), produziu apressórios globosos 24 HAI; os demais isolados não produziram apressórios. C. gloeosporioides isolados IH, IF e IM produziram células conidiogênicas 48 HAI. Acérvulos foram produzidos 72 HAI, por C. gloeosporioides (IH) e 96 horas por C. dematium. O isolado IM colonizou tecidos de plantas de cafeeiro, produzindo conidióforos, no entanto, sem produção de acérvulo. Os isolados mais agressivos foram IH e IF. The objective of this work was to follow the process of infection, colonization and reproduction of different isolates of Colletotrichum spp. in coffee plantlets, obtained by embryo culture, using scanning electron microscopy. The embryo explants were obtained from coffee seeds cv. Rubi. Plants produced in vitro were inoculated with 5µL of a 10(6) conidia.mL-1 spore suspension, on the hypocotyl region and leaves, wounding with an entomological needle. Isolates of Colletotrichum gloesporioides were obtained from stem (IS) and leaves (IL) from plants with symptoms of greasy leaf spot, and from mangos with symptoms of anthracnose (IM). Isolates of Colletotrichum dematium were obtained from healthy coffee plants. Three hours after inoculation (h.a.i.), leaves and hypocotyl fragments were transferred to 1.5mL-microtubes containing modified Karnovsky's fixative solution. Further samples were collected at 3, 5, 12, 16, 24, 48, 72, 96, 114 and 144 h.a.i. Conidia of all isolates adhered more frequently in the depressions of hypocotyls and guard-cells, forming a septum 5 h.a.i. Germ tubes were observed 12 h.a.i. starting from the extremities as well as laterally in the conidia. Appressoria were produced by C. dematium (globoses, trilobullated and foot and comma-shaped), and C. gloeosporioides, respectively globoses, 24 h.a.i. C. gloeosporioides (IH and IF) produced conidiogenic cells 48 h.a.i. Acervuli were produced 72 h.a.i. by C. gloeosporioides (IH), 96 h.a.i. by C. dematium. C. gloeosporioides isolated from mango colonized coffee plant tissues, producing conidiogenic cells without production of acervuli. The most aggressive isolates were IS and IL.

The potential use of the ribosomal DNA internal transcribed spacer (ITS) sequences in understanding the phylogeny and systematics of Colletotrichum species has been evaluated. Sequence data from a limited number of isolates revealed that in Colletotrichum species the ITS 1 region (50.3% variable sites) shows a greater degree of intra- and inter-specific divergence than ITS 2 (12.4% variable sites). Nucleotide sequences of the ITS 1 region from 93 isolates representing 18 Colletotrichum species were determined. Data for 71 of these isolates where molecular and morphological identities concurred were used for phylogenetic analysis. The size of the ITS 1 region varied from 159 to 185 base pairs. Maximum intraspecific divergence was recorded with C. acutatum (5.8%), and C. capsici showed the greatest level of interspecific divergence (8.9–23.3%). Parsimony and distance analyses gave similar tree topologies. The bootstrapped consensus parsimony tree divided the 18 Colletotrichum species into six phylogenetic groups, designated 1–6. These groups, however, are not congruent with species clusterings based on spore shape. For example, the straight cylindrical spored species were represented both in groups 1 and 6; group 6 also included the falcate fusiform spored species C. capsici. The molecular evidence suggests refinement of the species concepts of some of the taxa examined. In group 6, divergence between C. gloeosporioides and C. fuscum (0.6–3.0%) or C. kahawae (0.6–3.0%) or C. fragariae (0.6–4.2%) overlap the divergence (3.6%) within C. gloeosporioides. It is suggested that C. fuscum as well as C. kahawae and C. fragariae fall within the group species C. gloeosporioides. ITS 1 data enabled clear distinction (7.1%) of Colletotrichum isolates from maize and sorghum into C. graminicola and C. sublineolum, respectively (group 2). Species such as C. acutatum, C. coccodes, C. dematium, and C. trichellum can be clearly distinguished based on ITS 1 sequence divergence, but C. destructivum cannot be confidently separated (98% homology) from C. linicola. Colletotrichum dematium f. truncatum is distinct (12.9%) from C. dematium and should probably be called C. truncatum. Key words : Colletotrichum species, rDNA, ITS 1, nucleotide sequence, phylogeny, systematics.

Botrytis allii and Collectotrichum dematium are onion pathogens which can infect in the field and cause decay in storage. Some phenolics can hinder development of these fungi, but the effect of cytokinins is not clear. Cytokinins (kinetin or 6-benzyladenine) or phenolics (caffeic or chlorogenic acids) were added to agar at concentrations of 0 to 10(-3) M. Cultures were continuously irradiated with fluorescent light or maintained in the dark for 6 days. On unamended media, final mycelial elongation was 45 or 17.8 mm and sporulation was 28 or 10.6 x 10(4) spores/ml for Botrytis and Colletotrichum, respectively. For Botrytis, mycelial elongation was slightly (5%) but significantly increased and sporulation increased by 21% by incubation on phenolics as compared to cytokinins. Mycelial extension of Colletotrichum was not affected by amendment. Sporulation of Colletotrichum on kinetin was 16 to 28% greater than on the other amendments. As amendments concentration increased elongation of mycelia of both fungi decreased. Sporulation of Botrytis increased by 60% as amendment concentration increased from 0 to 10(-5) M and then decreased 25% at 10(-3) M. As amendment concentration increased from 0 to 10(-3) M, sporulation of Colletotrichum increased by 45%. Incubation in light increased mycelial extension 3 to 17% for Botrytis and Colletotrichum respectively, and sporulation was increased approximately 78% for both fungi. These compounds do not appear to inhibit development of these Botrytis or Colletotrichum species in culture.

Colletotrichum spp. are known to occur on and cause diseases of Proteaceae, but their identities are confused and poorly understood. The aim of the present study thus was to identify accurately the Col- letotrichum spp. associated with diseases of cultivated Proteaceae. Colletotrichum spp. associated with pro- teaceous hosts growing in various parts of the world were identified based on morphology, sequence data of the internal transcribed spacer region (ITS-1, ITS- 2), the 5.8S gene, and partial sequences of the b- tubulin gene. Four species of Colletotrichum were found to be associated with Proteaceae. Colletotri- chum gloeosporioides, a cosmopolitan species known to occur on numerous hosts, was isolated from Protea cynaroides cultivated in South Africa and Zimbabwe, and from a Leucospermum sp. in Portugal. A recently described species, C. boninense was associated with Zimbabwean and Australian Proteaceae but also oc- curred on a Eucalyptus sp. in South Africa. This rep- resents a major geographical and host extension for the species and a description of the African strains is

Three isolates of the fungal pathogen Colletotrichum dematium var. truncata were obtained from soybean ( Glycine max ) during the 1975 growing season in central and southern Illinois and labeled Cd-1, Cd-2 and Cd-3. The three isolates produced curved conidia measuring between 17.8 to 23.3 µ long and 3.2 to 5.1 µ wide. Growth rate and spore production were variable among the three isolates with Cd-3 producing the most spores per cm 2 of colony growth and Cd-2 producing the largest colony growth at 25° C. Isolate Cd-1, found to be tolerant to benomyl in vitro, showed a uniform radial-growth pattern on potato-dextrose agar amended with 1 to 350 µg/ml commercial benomyl, while isolates Cd-2 and Cd-3 showed a bimodal-type growth curve. Colletotrichum glycine and Coltetotrichum musae were sensitive to benomyl.

テンサイの一系統「TK-76-49/2mm-CMS」の採種圃において炭そ病菌によると認められる病害が大発生し,同系統のテンサイ(原料用)でも本病が発生した。病斑は主として葉柄にあらわれ,採種テンサイでは花茎,葉および開花期に花の各部分が侵害され,激しい場合は黒変,枯死した。これらの病斑部から炭そ病菌が高率で分離された。分離供試菌はテンサイ,飼料ビート,食用ビート,フダンソウなどアカザ科植物に対し,強い病原性を有したが,ダイズ,ネギ属には示さなかった。供試菌はColletotrichum dematium f. spinaciae (Ellis et Halst.) v. Arxと同定された。原料テンサイ畑での発病は品種・系統間で明瞭な差が認められたのでフダンソウ属植物12種に対し,接種実験を行った結果,いずれの品種も発病したが,特に「TK-76-49/2mm-CMS」および「TK-76-49/2mm-CMS」を種子親とした雑種第1代品種など4品種・系統が著しく罹病性であった。日本ではテンサイの炭そ病としてC. omnivorum (=C. dematium)による心葉黒枯病が報告されているが,病原性が確認されていない。今回発生した本病の病原は上記と同一と考えられるが,病徴が大きく異なる。したがって著者らは心葉黒枯病をテンサイ炭そ病(Sugar beet anthracnose)と改名することを提案した。

Colletotrichum dematium caused a root disease of table beet. Compared with C. atramentarium it was more pathogenic on beet and spinach and less pathogenic on carrot, potato, and tomato. With both species of fungi, at least 60 hours at high humidity was best for foliage infection to become well established. Beet seedlings were more susceptible to C. dematium than partially grown beet roots. Pathologically and morphologically, the beet isolate of Colletotrichum conformed to descriptions of C. spinaciae, a synonym of C. dematium.A culture seeding rate of 200,000 spores/ml was required for optimum spore production with C. dematium. Optimum growth and sporulation occurred at 22° to 24 °C. Growth and sporulation of the fungus was inhibited at 5° and 31 °C and 10° and 29 °C, respectively.C. dematium may not be an important pathogen of beets as it only occurred where beets were grown successively in the same soil.

Since Arx (1957) published the results of his morphological studies on Colletotrichum Corda, little work has been done on the experimental justification or refutation of the synonymies which he proposed. C. trichellum was cited as a facultative synonym of C. dematium. The two species are here contrasted and evidence is presented to justify the retention of the specific status for both fungi. The behaviour of single spore isolates on agar media is described and particular reference is made to the morphology of the fructifications and the conidia and to the development of appressoria. It is also suggested that appressorial characters will be of additional use in the future identification of Colletotrichum species.

A fungus causing necrosis on pods of Albizzia lebbek Benth. was collected in the vicinity of Varanasi, India. Leaflets and other parts of the plant were free from infection. Spots on the pods appeared in July and August and were small, circular to irregular, but finally coalesced and formed larger patches on the pods (FIG. 1). Fructifications which appeared on the infected areas were identified as a species of Colletotrichum, closely resembling C. dematium (Pers. ex Fr.) Grove f. truncata (Schw.) von Arx (Dr. J. A. von Arx, personal communication). In October, with the onset of cooler temperatures, a whitish growth appeared in the necrotic lesions, grew rapidly and covered large portions of the lesions (FIG. 2). This whitish growth was identified as Acremonium sordidulum W. Gams & D. Hawks. on the basis of its

South African bituminous coal can be converted by controlled wet oxidation to a highly oxidized water-insoluble product (oxihumic acids) and water-soluble oxifulvic acids (OFA). OFA, OFA-Cu and OFA-Fe, including various complexes, were evaluated against four fungal ( Aspergillus flavus, Fusarium oxysporum, Colletotrichum dematium and Alternaria cassiae) and three bacterial ( Erwinia carotovora, Pseudomonas syringae and Clavlbacter michiganense pv. michiganense) plant pathogens. CuSO 4 and CuSO 4 & FeSO 4 significantfy reduced growth of Erwinia, Clavibacter and Pseudomonas when compared to the control. CuOCI significantly reduced growth of Erwinia and Clavibacter. OFA, OFA-Fe, FeSO 4 , OFA-Cu & OFA-Fe and OFA-Cu reduced the growth of Pseudomonas and with the exception of the latter two, Clavibacter. CuSO 4 inhibited the growth of Colletotrichum. Alternaria and Fusarium significantly. OFA-Cu & OFA-Fe reduced the growth of Colletotrichum when compared to the control whereas OFA-Cu reduced growth in Alternaria significantly.

Background Anthracnose, caused by Colletotrichum dematium, is a serious threat to the production and quality of mulberry leaves in susceptible varieties. Control of the disease has been a major problem in mulberry cultivation. Some strains of Burkholderia cepacia were reported to be useful antagonists of plant pests and could increase the yields of several crop plants. Although B. cepacia Lu10-1 is an endophytic bacterium obtained from mulberry leaves, it has not been deployed to control C. dematium infection in mulberry nor its colonization patterns in mulberry have been studied using GFP reporter or other reporters. The present study sought to evaluate the antifungal and plant-growth-promoting properties of strain Lu10-1, to clarify its specific localization within a mulberry plant, and to better understand its potential as a biocontrol and growth-promoting agent. Results Lu10-1 inhibited conidial germination and mycelial growth of C. dematium in vitro; when applied on leaves or to the soil, Lu10-1 also inhibited the development of anthracnose in a greenhouse, but the effectiveness varied with the length of the interval between the strain treatment and inoculation with the pathogen. Strain Lu10-1 could survive in both sterile and non-sterile soils for more than 60 days. The strain produced auxins, contributed to P solubilization and nitrogenase activity, and significantly promoted the growth of mulberry seedlings. The bacteria infected mulberry seedlings through cracks formed at junctions of lateral roots with the main root and in the zone of differentiation and elongation, and the cells were able to multiply and spread, mainly to the intercellular spaces of different tissues. The growth in all the tissues was around 1-5 × 105 CFU per gram of fresh plant tissue. Conclusions Burkholderia cepacia strain Lu10-1 is an endophyte that can multiply and spread in mulberry seedlings rapidly and efficiently. The strain is antagonistic to C. dematium and acts as an efficient plant-growth-promoting agent on mulberry seedlings and is therefore a promising candidate as a biocontrol and growth-promoting agent.