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Colletotrichum is one of the most important plant pathogenic genera of fungi due to its scientific and economic impact. Colletotrichum spp. can infect a wide range of hosts, causing losses in crops of major importance worldwide, such as soybean. In the past, soybean anthracnose was mainly caused by C. truncatum, but during the last decade, other species have been identified at an increasing rate, becoming one of the most important limiting factors to soybean production in several regions. To gain a better understanding of the evolutionary origin of soybean anthracnose, we compared the repertoire of effector candidates of four Colletotrichum species pathogenic to soybean and eight pathogens of other hosts. Our results show that the four species infecting soybean belong to two lineages and do not share any of the lineage specific effector candidates identified. These results strongly suggest that two Colletotrichum lineages have acquired the capability to infect soybean independently. This study also provides, for each lineage, a set of candidate effectors encoding genes that may have important roles in pathogenicity towards soybean offering a new resource useful for further research on soybean anthracnose management.

is the causal agent of lupin (

Although lupin anthracnose caused by

Colletotrichum is a large genus of plant pathogenic fungi comprising more than 200 species. In this work, we present the genome sequences of four Colletotrichum species pathogenic to soybean: C. truncatum, C. plurivorum, C. musicola, and C. sojae. While C. truncatum is globally considered the most important pathogen, the other three species have been described and associated with soybean only recently. The genome sequences will provide insights into factors that contribute to pathogenicity toward soybean and will be useful for further research into the evolution of Colletotrichum.

is the causal agent of lupin (Lupinus albus L.) anthracnose, a destructive seed-borne disease affecting stems and pods. Despite that several biological studies have been carried out on this pathogen, the production of secondary metabolites has not yet been investigated. Thus, a strain of C. lupini, obtained from symptomatic stems of L. albus, has been grown in vitro to evaluate its ability to produce bioactive compounds. From its culture filtrates, a 3-substituted indolinone, named lupindolinone, and a 5,6-disubstituted tetrahydro-α-pyrone, named lupinlactone, were isolated together with the known (3R)-mevalonolactone and tyrosol. Lupindolinone and lupinlactone were characterized as 3-ethylindolin-2-one and 5-hydroxy-6-methyltetrahydropyran-2-one by spectroscopic methods (essentially nuclear magnetic resonance [NMR] and high-resolution electrospray ionization mass spectrometry [HR ESI-MS]). The R absolute configuration (AC) at C-5 of lupinlactone was determined by applying the modified Mosher’s method. Thus, considering its relative stereochemistry assigned by NMR spectroscopy, the AC of lupinlactone could be formulated as 5R,6S. Lupindolinone was isolated as racemic mixture as shown by investigation using chiroptical methods. The metabolites were assayed in different biological tests and proved to have some activities at the used concentration.

Soybean (Glycine max L.) is one of the most important crops worldwide as a source of protein-rich foods and animal feeds. Anthracnose, one of the major limiting factors to soybean production (Dias et al. 2016), is caused by species such as Colletotrichum truncatum, C. sojae, and C. plurivorum (Damm et al. 2009, 2019). In December 2016 and 2017, soybean plants of cultivars Monsoy 8768 and Pioneer y-70 with typical symptoms of anthracnose (necrotic and irregular brown lesions on stems, leaves, and pods) were collected in Mato Grosso, Brazil. Commercial fields sampled showed 10 to 15% incidence of anthracnose in 1 ha in each sampled area. In total, 10 different geographic locations were sampled. Colletotrichum strains were isolated and cultured on potato dextrose agar at 25°C with a 12-h light photoperiod from surface-disinfected (70% alcohol followed by 0.5% sodium hypochlorite) plant tissues. Among others, three single-spore isolates (LFN0048 from Sinop, LFN0074 and LFN0090 from Lucas do Rio Verde) showed different morphology; isolates LFN0048 and LFN0074 were selected for further characterization. Total DNA was extracted and partial glyceraldehyde 3-phosphate dehydrogenase (GAPDH), histone H3 (HIS3), and β-tubulin (TUB2) genes were amplified and sequenced. The sequences were deposited in GenBank (accession numbers MN604249 and MK163893 for HIS3, MN604248 and MK142674 for GAPDH, and MN604250 and MK142675 for TUB) and were compared with most similar reference sequences of Colletotrichum (Damm et al. 2019). Both isolates clustered with Colletotrichum musicola epitype (CBS 132885), showing 100 and 98.5% similarity in GAPDH, 99.5 and 98.9% in HIS3, and 99.2% in TUB2. On PDA, colonies showed dark-gray aerial mycelium with entire margins, reverse violaceous-black. Conidia and ascospore size and shape match those previously described by Damm et al. (2019): 12.12 to 15.86 × 4.93 to 6.95 µm and 15.5 to 19.34 × 5 to 7.84 µm, respectively (n = 100). Appressoria (n = 50) were single or in loose groups, violaceous-black with predominant obovoid, truncated, and cylindrical shapes, with smooth, undulate, or lobate margin, and 9.25 to 29.79 × 7.22 to 21.06 µm. Perithecia, paraphyses; and unitunicate eight-spored asci were also observed. Asci were cylindrical to clavate, smooth-walled, and 48.12 to 68.78 × 9.59 to 14.47 µm (n = 50). Soybean anthracnose is seed-borne (Dias et al. 2018; Rogério et al. 2017); therefore, pathogenicity tests were carried out on pregerminated seeds. Five seeds of Brasmax 8579 cultivar were inoculated with 10 µl of a conidial suspension (106 conidia/ml) that was placed in the emerging radicle, and five mock-inoculated seeds were used as a control. Seedlings were planted in vermiculite and incubated at 25°C with a 12-h photoperiod. After 7 days, inoculated plants showed necrotic lesions on the cotyledons, leaflets, and hypocotyl, whereas control plants remained asymptomatic. The experiment was repeated three times. C. musicola was reisolated from the symptomatic tissues, and the identity was confirmed by morphology and multilocus phylogeny. Until now, C. musicola has been reported to be associated with Musa sp. (Damm et al. 2019) and Colocasia esculenta (Vásquez-López et al. 2019) in Mexico, and with Phaseolus lunatus in Brazil (Cavalcante et al. 2018). To our knowledge, this is the first report of C. musicola joining a group of new and emergent species of Colletotrichum causing anthracnose in soybean-producing regions around the world.

Colletotrichum is an important fungal plant pathogen, yet an uncommon cause of human disease. Herein we report a case of invasive, cutaneous infection in a stem cell transplant recipient due to Colletotrichum species, with accompanying review of the literature. The infection was successfully treated with a combination of liposomal amphotericin B and voriconazole. Multilocus phylogenetic analysis revealed that the distinct isolate belongs to Colletotrichum siamense, a member of the Colletotrichum gloeosporioides species complex not previously described as a human pathogen. Colletotrichum infection remains in the differential for skin lesions in the immune compromised host.

Apple is an important crop in United Kingdom, with a total production of 233,750 tonnes in 2011. Symptoms of apple bitter rot were observed on apple fruits (Malus domestica L.) in the Newcastle area, United Kingdom, in October 2008. Lesions were round, 1 to 5 cm in diameter, brown and dry, with acervuli producing yellowish spore masses in concentric bands. Infected material was sent to the W-HRI (University of Warwick) for identification of the causal agent. Fungal isolates with morphological characteristics similar to those of Colletotrichum acutatum sensu lato were isolated from diseased fruits. Monoconidial isolates were grown on PDA at 25°C with a 12-h light period. The cultures were light gray, with cottony aerial mycelium getting darker with age and with color ranging from whitish to dark gray on the reverse side of the colony. The cultures have yellowish spores masses and dark melanized structures similar to acervuli. Colletotrichum spp. are difficult to identify solely on morphology; therefore, representative isolates were used for multi-locus gene sequencing and characterization (1). Genomic DNA was extracted using a modified Chelex100 protocol. Three loci were amplified and sequenced: the ITS region was amplified and sequenced using the universal primers ITS4 and ITS5. Primers TB5 and TB6 were used for the amplification and sequencing of the variable region of the TUB gene. Primers GDF1 and GDR1 were used to amplify a 200-bp intron region of the GAPDH gene. No differences were found among the strains at any of the loci. One sequence for each locus has been deposited in GenBank under accessions KF834206 (ITS), KF834207 (TUB), and KF834208 (GAPDH). In GenBank, ITS sequences matched with 100% identity to C. higginsianum (EU400147) and to C. gloeosporioides (AJ301931 to 972); and with identity between 99.6 and 99.8% with sequences belonging to C. godetiae (part of C. acutatum species complex). The TUB sequences match with 100% identity to more than 25 sequences belonging to C. godetiae. The GAPDH sequences match with 100% identity to JQ948739 and 35 belonging to C. godetiae strains IMI 381927 and CBS 131331. A multilocus phylogenetic tree (ITS, TUB, and GAPDH) was reconstructed using sequences of reference strains belonging to C. higginsianum, C. gloeosporioides, C. godetiae, and related species. The phylogenetic tree confirmed the identity of the strains isolated from apple as C. godetiae. Koch's postulates were tested with representative isolate by artificial inoculation of 12 healthy fruits of the cv. Golden Delicious. Fruit surfaces were sterilized with 70% ethanol, wounded with a sterile needle, and then inoculated with a plug of actively growing mycelium prepared from a 10-day-old culture grown on PDA. Inoculated fruits were incubated in sterile conditions at 25°C with a 12-h photoperiod. In 83% of fruits, symptoms appeared between 7 and 15 days later. The rot begins as light brown, circular lesion getting darker with orange spore masses. Fungal colonies isolated from the lesions and cultured on PDA have identical morphological characteristics of the isolate used for the pathogenicity assay. To the best of our knowledge, this is the first report of apple bitter rot caused by C. godetiae in the United Kingdom. Apple bitter rot is spread worldwide and in moist, temperate regions it is considered one of the most important diseases causing considerable crop losses. Since the losses are more severe under prolonged warm and wet weather conditions, bitter rot caused by C. acutatum species may become an emerging problem in the United Kingdom in the near future, and may require investigation of management practices to control this new disease. References: (1) R. Baroncelli. Colletotrichum acutatum sensu lato: From diversity study to genome analysis. Coventry, United Kingdom, PhD thesis, 2012. (2) U. Damm et al. Stud. Mycol. 73:37, 2012.

International audience; Bitter rot is one of the prevalent diseases of apple (Malus pumila Mill.) worldwide. The disease affects the fruit preharvest in orchards and/or postharvest in storage, resulting in considerable economic losses. Until recently the reported causal agents in Europe belong to the Colletotrichum acutatum species complex (Baroncelli et al. 2014; Nodet et al. 2016); however, species belonging to C. gloeosporioides species complex were reported in the United States (Munir et al. 2016), South America (Velho et al. 2018), Korea (Park et al. 2018), and recently in Belgium (Grammen et al. 2019). In September 2017, bitter rot symptoms were observed on apple fruit (cultivars Joya Cripps Red, Granny Smith, and Pink Lady) in four orchards in the region of Occitanie in France. The rot began as circular brown spots, 1 to 2 mm in diameter, which enlarged rapidly. Sixteen isolates were obtained from symptomatic apples by culturing pieces of necrotic tissue on potato dextrose agar. Cultures showed light-gray, cottony mycelium that became darker with age, with the reverse color being brownish and becoming black with age. Conidia were produced in small orange masses and were mainly cylindrical, with rounded ends. For all isolates, the production of perithecia was observed in culture, and asci and ascospores were observed under the microscope. The width and length of 50 conidia were examined and ranged from 3.1 to 4 µm (average 3.5 µm) and from 8 to 13 µm (average 10.5 µm), respectively. Based on these morphological characteristics, those isolates correspond to teleomorph of species belonging to C. gloeosporioides species complex (Weir et al. 2012). Total genomic DNA was extracted from the 16 isolates, and the internal transcribed spacer region of rDNA was amplified using the universal primers ITS4 and ITS5 and then sequenced. For all isolates, the resulting sequences were 100% identical to C. fructicola sequences obtained by a BLAST search in GenBank. Three other loci (partial GAPDH, TUB2, and ApMat genes) were amplified and sequenced to further characterize two isolates (UBOCC-A-118064 and UBOCC-A-118065; GenBank accession nos. MK114103 to MK114110, respectively). Multilocus phylogenetic analysis carried out with the obtained and reference sequences (Da Lio et al. 2018) revealed that the isolates clustered within C. fructicola, as suggested by the BLAST results; this is also consistent with their initial identification as C. gloeosporioides. To confirm Koch’s postulates, for the two characterized isolates, 10 ‘Golden Delicious’ apples were surface sterilized and then wound inoculated with 20 μl of a conidial suspension (105 conidia/ml). After 10 days of incubation at 20°C, symptoms identical to those initially observed developed around the inoculation point, whereas controls inoculated with water remained symptomless. Fungal thalli reisolated from the lesions were morphologically similar to the original isolate. To our knowledge, this is the first report in Europe of C. fructicola causing bitter rot on apple. According to Munir et al. (2016), C. fructicola was reported to be more aggressive than species belonging to the C. acutatum species complex such as C. fioriniae previously identified in France (Nodet et al. 2016); moreover, this species is associated with Glomerella leaf spot, an emerging leaf disease never described in Europe (Velho et al. 2018). All those points encourage the development of species-specific management strategies for this pathogen in European countries.

Colletotrichum orchidophilum is a plant-pathogenic fungus infecting a wide range of plant species belonging to the family Orchidaceae. In addition to its economic impact, C. orchidophilum has been used in recent years in evolutionary studies because it represents the closest related species to the C. acutatum species complex. Here, we present the first-draft whole-genome sequence of C. orchidophilum IMI 309357, providing a resource for future research on anthracnose of Orchidaceae and other hosts.

Perspective Colletotrichum spp. infect a wide diversity of hosts, causing plant diseases on many economically important crops worldwide. The genus contains approximately 189 species organized into at least 11 major phylogenetic lineages, also known as species complexes. The Colletotrichum acutatum species complex is a diverse yet relatively closely related group of plant pathogenic fungi within this genus. Within the species complex we find a wide diversity of important traits such as host range and host preference, mode of reproduction and differences in the strategy used to infect their hosts. Research on fungal comparative genomics have attempted to find correlations in these traits and patterns of gene family evolution but such studies typically compare fungi from different genera or even different fungal Orders. The C. acutatum species complex contains most of this diversity within a group of relatively closely related species. This Perspective article presents a review of the current knowledge on C. acutatum phylogeny, biology, and pathology. It also demonstrates the suitability of C. acutatum for the study of gene family evolution on a fine scale to uncover evolutionary events in the genome that are associated with the evolution of phenotypic characters important for host interactions. info:eu-repo/semantics/publishedVersion

A new tetrasubstituted pyran-2-one and a new dihydrobenzofuran, named colletochlorins E and F (1 and 2, respectively), were isolated from the culture filtrates of the fungus Colletotrichum higginsianum together with the already known colletochlorin A, 4-chloroorcinol, and colletopyrone. Colletochlorin E, the main metabolite, and colletochlorin F were characterized by spectroscopic (NMR, HRESIMS) and chemical methods as 3-[7-chloro-4-hydroxy-2-(1-hydroxy-1-methylethyl)-6-methyl-2,3-dihydrobenzofuran-5-ylmethyl]-4-hydroxy-5,6-dimethylpyran-2-one and 7-chloro-2-(1-hydroxy-1-methylethyl)-6-methyl-2,3-dihydrobenzofuran-4-ol, respectively. The absolute configuration 2′S of 1 was deduced by X-ray diffractometric analysis, whereas 2S of 2 was deduced by comparison of its NMR and CD data with those of 1. When assayed by leaf puncture on Sonchus arvensis and tomato leaves, 2 caused quite large necrosis (>1 cm), whereas 4-chloroorcinol proved to be the most active compound. These results were confirmed by those obtained in assays on Lemna minor and Phelipanche ramosa seed germination. Furthermore 1, colletochlorin A and colletopyrone were less or modestly active in the latter assay, respectively. Interestingly, the phytotoxicity was not associated with an antibiotic activity, whereas only 4-chloroorcinol and colletochlorin F exhibited zootoxic activity.

Colletotrichum graminicola is the causal agent of maize (Zea mays) anthracnose. The most common symptoms are leaf blight, top dieback, and stalk rot (Munkvold and White 2016). Owing to its negative impact on maize production, it is important to study the distribution and propagation of this disease. In September 2018, maize stem samples exhibiting symptoms of anthracnose stalk rot (glossy, black, and irregularly shaped lesions) were collected from a field in the Odžak (Posavska Mahala) region of northeastern Bosnia and Herzegovina. Stem samples, approximately 50 mm2, were dissected and surface disinfected for 90 s in 20% sodium hypochlorite (v/v) and rinsed three times in sterile distilled water. The samples were transferred to one-half-strength acidified potato dextrose agar (PDA) Petri dishes supplemented with ampicillin (100 µg/ml) and incubated for 4 to 6 days at 25°C (Sukno et al. 2008). Single-spore isolates from three distinct stem pieces were cultured on PDA. The aerial mycelium was dark gray with orange-colored spore masses, and conidia were falcate, slightly curved, tapered toward the tips, and produced in acervuli with setae. The length and width of 50 conidia were measured and ranged from 25 to 35 µm (average, 29.8 µm; standard deviation, ± 2.0 µm) and from 7 to 11 µm (average, 9.0 µm; standard deviation, ± 0.7 µm), respectively. These morphological characteristics are consistent with C. graminicola (Bergstrom and Nicholson 1999). Two isolates were grown in potato dextrose broth for 3 days at 25°C, and total genomic DNA was extracted following the protocol of Baek and Kenerley (1998). The internal transcriber spacer (ITS) region of rDNA was amplified using universal fungal primers ITS4 and ITS5 and consequently sequenced. GenBank BLAST analysis revealed that the sequences were 100% identical to ITS rDNA sequences of C. graminicola isolates. One sequence was deposited in GenBank under accession number MK955539. These results were consistent with the initial identification of C. graminicola. To confirm Koch’s postulates, maize plants (vegetative stage V3) were placed horizontally in a tray for inoculation and 20 droplets (7.5 µl) of a suspension of 3 × 105 conidia/ml were placed on the surface of the third leaf. The trays were closed to retain moisture and incubated overnight at 23°C. The next day, the plants were returned to a vertical position and incubated in a growth chamber at 25°C with 80% humidity and a light cycle of 16 h of light and 8 h of dark (Vargas et al. 2012). After 6 days, the leaves of the inoculated plants presented brown elongated lesions with chlorotic margins and necrotic centers consistent with C. graminicola infection. Controls inoculated with water did not exhibit any symptoms. Microscopic analysis of the surface of infected leaves revealed acervuli, setae, and conidia that were identical to the original isolates. To our knowledge, this is the first report of C. graminicola causing maize anthracnose in Bosnia and Herzegovina (Arsenijević et al. 1996). Previous reports have shown that maize anthracnose is an important disease in Croatia (Palaversic et al. 2009), and it has been reported in Slovenia. Because it may also be a threat for neighboring countries such as Serbia, Romania, and Hungary, where the cultivation of maize is an important component of the economy, continued surveillance is needed.

Background Many species belonging to the genus Colletotrichum cause anthracnose disease on a wide range of plant species. In addition to their economic impact, the genus Colletotrichum is a useful model for the study of the evolution of host specificity, speciation and reproductive behaviors. Genome projects of Colletotrichum species have already opened a new era for studying the evolution of pathogenesis in fungi. Results We sequenced and annotated the genomes of four strains in the Colletotrichum acutatum species complex (CAsc), a clade of broad host range pathogens within the genus. The four CAsc proteomes and secretomes along with those representing an additional 13 species (six Colletotrichum spp. and seven other Sordariomycetes) were classified into protein families using a variety of tools. Hierarchical clustering of gene family and functional domain assignments, and phylogenetic analyses revealed lineage specific losses of carbohydrate-active enzymes (CAZymes) and proteases encoding genes in Colletotrichum species that have narrow host range as well as duplications of these families in the CAsc. We also found a lineage specific expansion of necrosis and ethylene-inducing peptide 1 (Nep1)-like protein (NLPs) families within the CAsc. Conclusions This study illustrates the plasticity of Colletotrichum genomes, and shows that major changes in host range are associated with relatively recent changes in gene content. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2917-6) contains supplementary material, which is available to authorized users.

Although Colletotrichum acutatum was recently investigated and shown to be a species complex comprising about 30 species, the name is still used in its broad sense for anthracnose pathogens of fruits in Brazil. In this study, a multilocus molecular analysis was carried out based on a dataset of ITS, HIS3, GAPDH, CHS-1, TUB2 and ACT sequences of Colletotrichum strains belonging to the C. acutatum species complex from fruits collected in different regions in Brazil combined with sequences of ex-type and other reference strains of species belonging to this complex. The strains were revealed to belong to Colletotrichum nymphaeae, Colletotrichum melonis, Colletotrichum abscissum and one new species, namely Colletotrichum paranaense, from apple and peach. Morphological descriptions of the new species and a strain closely related to but diverging from C. melonis are provided. From the data presently available, the most common species on apple fruits in Brazil is C. nymphaeae. In a pathogenicity test, strains of all four species caused lesions on detached apple, peach and guava fruits, except for strain CBS 134730 that did not infect guava fruits.

Two new diterpenoid alpha-pyrones, named higginsianins A (1) and B (2), were isolated from the mycelium of the fungus Colletotrichum higginsianum grown in liquid culture. They were characterized as 3-[5a,9b-dimethyl-7-methylene-2-(2-methylpropenyl)dodecahydronaphtho[2,1-b]furan-6-ylmethyl]-4-hydroxy-5,6-dimethylpyran-2-one and 4-hydroxy-3-[6-hydroxy-5,8a-dimethyl-2-methylene-5-(4-methylpent-3-enyl)decahydronaphthalen-1-ylmethyl]-5,6-dimethylpyran-2-one, respectively, by using NMR, HRESIMS, and chemical methods. The structure and relative configuration of higginsianin A (1) were confirmed by X-ray diffractometric analysis, while its absolute configuration was assigned by electronic circular dichroism (ECD) experiments and calculations using a solid-state ECD/TDDFT method. The relative and absolute configuration of higginsianin B (2), which did not afford crystals suitable for X-ray analysis, were determined by NMR analysis and by ECD in comparison with higginsianin A. 1 and 2 were the C-8 epimers of subglutinol A and diterpenoid BR-050, respectively. The evaluation of 1 and 2 for antiproliferative activity against a panel of six cancer cell lines revealed that the IC50 values, obtained with cells reported to be sensitive to pro-apoptotic stimuli, are by more than 1 order of magnitude lower than their apoptosis-resistant counterparts (1 vs >80 mu M). Finally, three hemisynthetic derivatives of 1 were prepared and evaluated for antiproliferative activity. Two of these possessed IC50 values and differential sensitivity profiles similar to those of 1.

Fragaria × ananassa (common name: strawberry) is a globally cultivated hybrid species belonging to Rosaceae family. Colletotrichum acutatum sensu lato (s.l.) is considered to be the second most economically important pathogen worldwide affecting strawberries. A collection of 148 Colletotrichum spp. isolates including 67 C. acutatum s.l. isolates associated with the phytosanitary history of UK strawberry production were used to characterize multi-locus genetic variation of this pathogen in the UK, relative to additional reference isolates that represent a worldwide sampling of the diversity of the fungus. The evidence indicates that three different species C. nymphaeae, C. godetiae and C. fioriniae are associated with strawberry production in the UK, which correspond to previously designated genetic groups A2, A4 and A3, respectively. Among these species, 12 distinct haplotypes were identified suggesting multiple introductions into the country. A subset of isolates was also used to compare aggressiveness in causing disease on strawberry plants and fruits. Isolates belonging to C. nymphaeae, C. godetiae and C. fioriniae representative of the UK anthracnose pathogen populations showed variation in their aggressiveness. Among the three species, C. nymphaeae and C. fioriniae appeared to be more aggressive compared to C. godetiae. This study highlights the genetic and pathogenic heterogeneity of the C. acutatum s.l. populations introduced into the UK linked to strawberry production.

In 2012, Colletotrichum isolates were collected from field-grown safflower (Carthamus tinctorius) crops in central Italy from plants exhibiting typical anthracnose symptoms. Colletotrichum isolates were also collected from seed surfaces and from within seeds. The genetic variability of these isolates was assessed by a multilocus sequencing approach and compared with those from Colletotrichum chrysanthemi and Colletotrichum carthami isolates from different geographic areas and other Colletotrichumacutatum sensu lato-related isolates. Phylogenetic analysis revealed that all of the strains isolated from C.tinctorius belonged to the species described as C.chrysanthemi, whereas all of the strains belonging to C.carthami had been isolated from Calendula officinalis. Phenotypic characterization of isolates was performed by assessing growth rates at different temperatures, morphology of colonies on potato dextrose agar (PDA) and the size of conidia. All C.chrysanthemi isolates from safflower had similar growth rates at different temperatures, comparable colony morphologies when grown on PDA and conidial sizes consistent with previously described C.chrysanthemi isolates. Pathogenicity tests were performed by artificially inoculating both seeds and plants and confirmed the seedborne nature of this pathogen. When inoculated on plants, C.chrysanthemi caused the typical symptoms of anthracnose on leaves. This is the first record of this pathogen on C.tinctorius in Italy, and it presents an updated characterization of Colletotrichum isolates pathogenic to safflowers in Europe.

The presentations of the Special Interest Group meeting Colletotrichum: species, ecology and interactions, held on 1 August 2010 during IMC9 in Edinburgh, UK, are outlined. Seven research projects, ranged from systematics and population genetics to host-pathogen interactions and genome projects were presented. The meeting revealed that currently major species complexes in the genus Colletotrichum are being revised and the identities of many pathogens clarified on the basis of molecular phylogenies, and that the genomes of four species are sequenced and decoded providing an enormous amount of data that are used to increase our understanding of the biology of Colletotrichum species.

Lupin anthracnose is a major threat caused by the filamentous fungus Colletotrichum lupini. The genus Colletotrichum includes a wide number of phytopathogen species distributed worldwide. They were classified into 14 species complexes, with C. lupini belonging to the C. acutatum species complex. To date, studies performed on C. lupini, aimed at better understanding its phylogenetic classification and infectious lifecycle. But additional studies seemed necessary to increase our knowledge on (i) intraspecific diversity within the C. lupini species and (ii) the molecular determinants of pathogenicity. To address the first objective, a study was performed on strains from official collections and from isolates recently collected in the west of France. A low intra-specific phylogenetic diversity was found compared to the phenotypic diversity, notably characterized by contrasted aggressiveness between strains. The second objective was evaluated by determining fungal gene expression and protein synthesis during lupin infection by C. lupini using, respectively, a RNAseq-based transcriptomic approach and a mass spectrometry-based proteomic approach with a nLC Q-exactive Orbitrap. Taken together, our results highlighted that the dynamics of symptoms, gene expression and protein synthesis shared similarities to those of hemibiotrophic pathogens. In addition, few genes of unknwown or poorly-described functions were found to be specifically associated to the early or late stages of infection, suggesting that they may be of importance for pathogenicity. Functional validation will be discussed to confirm their role in promoting C. lupini pathogenicity.