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The leaf spot disease of Pongamia pinnata caused by an asperisporium-like asexual morph, which is usually referred to as Asperisporium pongamiae, is quite common during monsoon seasons in India. Phylogenetic analyses, based on LSU and rpb2 sequence data, and blast searches using ITS sequence data, revealed that this ascomycete forms a lineage within Mycosphaerellaceae distant from all other generic lineages. Pedrocrousiella gen. nov., with P. pongamiae comb. nov., based on Fusicladium pongamiae (≡ A. pongamiae), as type species is introduced for this lineage. This species has been considered the asexual morph of Mycosphaerella pongamiae (≡ Stigmatea pongamiae). However, this connection is unproven and was just based on the occasional association of the two taxa in some collections. Several attempts to induce the formation of a sexual morph in culture failed, therefore the putative connection between these morphs could not be confirmed. Asperisporium pongamiae-pinnatae is reduced to synonymy with P. pongamiae. Asperisporium pongamiae-pinnatae was introduced because of the wrong assumption that F. pongamiae had been described on another host, Pongamia globosa. But Fusicladium pongamiae was actually described in India on Pongamia glabra, which is a synonym of P. pinnata, and hence on the same host as Asperisporium pongamiae-pinnatae . Pedrocrousiella pongamiae clusters in a clade containing Distocercospora, Clypeosphaerella , and "Pseudocercospora "nephrolepidicola, a species which is not congeneric with Pseudocercospora. Phylogenetically, Pedrocrousiella is distant from the Asperisporium s. str. clade (type species A. caricae), which is more closely related to Amycosphaerella, Pseudocercosporella, Distomycovellosiella and Nothopassalora.

A cercosporoid fungus associated with leaf lesions of Dypsis lutenscens (Arecaceae) was observed in Chiang Rai, Thailand. This study describes the new species Pseudocercospora dypsidis based on morphological characteristics and phylogenetic analyses from three gene regions, ITS, TEF-1α, and ACT. Single gene analyses are generally insufficient for identification of Pseudocercospora species, or for segregation of other genera in the Pseudocercospora complex. A list is provided of all Pseudocercospora species known from Thailand and the need to confirm their identifications by a polyphasic approach is stressed.

Deep-sea sediments are now recognized as a home for rich and largely microbial community. Recently, it has been believed in an increasing number of studies that bacteria could be abundant in deep-sea sediments of many types; however, fungi in deep-sea sediments remain relatively unknown. The phylogenetic diversity and bioactivity of culturable deep-sea-derived fungi from Okinawa Trough sediments were investigated in traditional method combined with fungal identification of molecular biology in this study. A total of 76 isolates belonged to 15 fungal taxa were recovered in a harsh condition of low nutrient and low temperature, indicating that the fungal communities in deep-sea sediments from Okinawa Trough were relatively abundant and diversified. Aspergillus, Cladosporium, and Penicillium were the dominant fungal genera, while Mycosphaerella, Purpureocillium, and Schizophyllum were relatively rare in the deep-sea sediments from Okinawa Trough. Among the six genera recovered, Mycosphaerella was firstly recovered from deep-sea sediments in this study. Moreover, about 75% of the extracts from the 15 fungal representative isolates displayed distinct bioactivity against at least one indicator bacterium or marine macrofouler, emphasizing the potentials of these deep-sea-derived fungi from Okinawa Trough as producers of bioactive metabolites. Notably, isolates Cladosporium oxysporum SCSIO z001 and Penicillium citrinum SCSIO z049 displayed a wide spectrum of bioactivities, isolates Cladosporium cladosporioides SCSIO z015, Cladosporium sphaerospermum SCSIO z030, and Penicillium verruculosum SCSIO z007 exhibited a strong anti-bacterial-growth activity, and isolate Penicillium chrysogenum SCSIO z062 displayed a strong anti-larval-settlement activity. These results suggest that these isolates deserved further study as potential sources of novel bioactive metabolites.

Objective In the present study, Gentiana rigescens was screened for fungi communities to clarify their diversity and community assemblage in hosts. Meanwhile, the identification and activity assays of the strains were also conducted. Methods By culture-dependent (endophytic fungi isolations from plant sections) and culture-independent (metagenomic library and cloning from plant sections) techniques, fungi communities were studied. The metagenomic library was generated using direct DNA isolation of whole plants, plant radixes, plant stems, plant leaves, plant flowers and soils around the plant. Meanwhile, endophytes were isolated from all parts of G. rigescens plants. After fermentation of the fungi isolations, all the isolates were evaluated for their cytotoxicity against four kinds of human cancer cell lines (HCT116, BEL7404, A549, MDA-MB-231). Results Eventually, 200 strains were isolated and 103 strains were further identified through the internal transcribed spacer (ITS, ITS1 and ITS2 regions) sequence by using the universal primers ITS5 and ITS4. A total of 59,106 fungal sequences corresponding to 374 putative operational taxonomic units (OTU) were identified by 454 pyrosequencing. Through 454 pyrosequencing, the main fungal genera were Sebacina, Botrytis, Mycosphaerella, Boletus and Gibberella, and the major fungal genera which were directly isolated were Aspergillus, Fusarium, Penicillium and Alternaria. Activity assays showed strains 5–26 (Aspergillus sp.) and 6–2 (Fusarium avenaceum) had the outstanding cytotoxicity to all the tested cell lines with IC50 values Conclusion This study revealed the abundance of endogenetic fungal resources and a variety of genetic information in G. rigescens by high-throughput 454 sequencing technology and fungi isolation methods. Activity assays indicated that endophytes were a promising natural source of potential anticancer agents.

Seeds are involved in the transmission of microorganisms from one plant generation to the next, acting as initial inoculum for the plant microbiome, therefore provide a key source of variability in plants. This study aimed to characterize the seed bacteria and fungi communities in Elymus nutans, a dominant perennial grass growing in the Qinghai Tibet Plateau (QTP) and explore the effects of plant growth location on the seed microbiome. Seeds were collected from plants growing in four locations in the QTP. The seed microbial community was examined by Illumina MiSeq sequencing of DNA extracted from the surface sterilized seeds. The seed bacterial community was dominated by the bacteria phylum Proteobacteria (98%) and fungal phyla Ascomycota (83%) and Basidiomycota (15%). At the lower taxonomic level, the bacterial genus Pseudomonas dominated in all four locations with an average relative abundance of 83% whereas the fungal genera that dominated the seed microbiome was diverse, the most prominent being Epichloe, Pyrenophora, Mycosphaerella and Bullera. Ecologically important bacterial family Nitrosomonadaceae (nitrifiers) and fungal phylum Glomeromycota (arbuscular mycorrhizal fungi) were detected in this study for the first time as seed endophytes. The Elymus nutans seed bacterial community was not impacted by the plant growth location, in contrast, the seed fungal community varied significantly in four locations. The seeds of Elymus nutans host diverse endophytic bacteria and fungi. Unlike the bacteria, the host plant selection of seed fungal endophytes was observed to have been affected by plant growth location. Positive and negative associations in the Elymus nutans seed microbiome were observed.

The frequency and diversity of fungi in branches, roots and soil was examined in 3–10-years-old diseased Juniperus x media trees growing in the surroundings of the sewage treatment facility in Poznań. Symptoms of branch dieback appeared first on the older parts inside the crown and mostly in the lower part of trees subsequently spreading upwards and outwards. Our analyses included extraction of environmental rDNA from branches, roots and soil, amplification of the rDNA with fungi specific primers and sequencing. Fungal taxa from Ascomycota, Basidiomycota, Chytridiomycota, Glomeromycota and Zygomycota were detected with a total of 695, 135 and 196 taxa in branches, roots and soil, respectively. Fungal communities included plant pathogens, opportunistic pathogens, epiphytes or endophytes, mycorrhizal taxa, saprotrophs common on organic debris and in soil, human and animal pathogens, entomopathogenic taxa, mycoparasites, white and black yeasts, taxa with antagonistic and medicinal properties and lichenized fungi. The frequency of potential plant pathogens was 2.64–33.12% in branches, 0.88% in roots and 1.29–2.93% in soil. The most common pathogens were species from Chalara, Cytospora, Fusarium, Ilyonectria, Mycosphaerella, Setomelanomma (Ascomycota) and Armillaria, Rhizoctonia (Basidiomycota) genera. The less frequent pathogens included species from Leptosphaeria, Lophodermium and Septoria genera. In conclusion, oxygen deficiency and the presence of poisonous gases in the air around the sewage plant is likely to have had damaging effects on plants infected or colonized by opportunistic and facultative parasites.

A survey of the endophytic fungi in fronds of Livistona chinensis was carried out in Hong Kong. The endophyte assemblages identified using morphological characters consisted of 16 named species and 19 'morphospecies', the latter grouped based on cultural morphology and growth rates. Arrangement of taxa into morphospecies does not reflect species phylogeny, and therefore selected morphospecies were further identified based on ribosomal DNA (rDNA) sequence analysis. The 5.8S gene and flanking internal transcribed spacers (ITS1 and ITS2) regions of rDNA from 19 representative morphospecies were amplified by the polymerase chain reaction and sequenced. Phylogenetic analysis based on 5.8S gene sequences showed that these morphospecies were filamentous Ascomycota, belonging in the Loculoascomycetes and Pyrenomycetes. Further identification was conducted by means of sequence comparison and phylogenetic analysis of both the ITS and 5.8S regions. Results showed that MS704 belonged to the genus Diaporthe and its anamorph Phomopsis of the Valsaceae. MS594 was inferred to be Mycosphaerella and its anamorph Cladosporium of the Mycosphaerellaceae. MS339, MS366, MS370, MS395, MS1033, MS1083 and MS1092 were placed in the genus Xylaria of the Xylariaceae. MS194, MS375 and MS1028 were close to the Clypeosphaeriaceae. MS191 and MS316 were closely related to the Pleosporaceae within the Dothideales. The other 5 morphospecies, MS786, MS1043, MS1065, MS1076 and MS1095, probably belong in the Xylariales. The value of using DNA sequence analysis in the identification of endophytes is discussed.

Purpose Microbial community composition is crucial for the flavor and quality of fermented foods. However, the microbiota of Chinese traditional dough starter (Jiaozi) from different origins has scarcely been studied. The aim of this study was to determine the composition of bacterial and fungal communities in six Jiaozi collected from two provinces in northwest China. Methods Our study determined the composition of bacterial and fungal communities in six Jiaozi through Illumina MiSeq sequencing of the 16S rRNA gene and the ITS regions. Result A total of 234 operational taxonomic units (OTUs) for bacteria and 490 OTUs for fungi were identified. Furthermore, Lactobacillus, Weissella, Acetobacter, Sphingomonas, and Serratia were identified as the predominant bacterial genera in Jiaozi samples, while Saccharomyces, Candida, Alternaria, unclassified Filobasidiales, and Mycosphaerella were the most abundant fungal genera. The results revealed that the six samples could be grouped into two groups based on their province of origin. In the results of PCA and HCA analysis, the first three principal components which were chosen could explain 99.93% and 90.99% of the total bacterial and fungal communities, respectively. Conclusion The results indicated high levels of bacteria and fungi in traditional Jiaozi and highlighted the possible influence of geographic areas on microbial diversity.

Grapevines (Vitis vinifera) are colonized by ubiquitous microorganisms known as endophytes, which may have advantageous or neutral effects without causing disease symptoms. Certain endophytes are uncultivable, so culture-independent approaches such as next generation sequencing (NGS) can help for a better understanding of their ecology and distribution. To date, there are no studies which directly link NGS results with taxa derived from a culturing approach, integrating morphological and multi-gene phylogenetic analysis of endophytes. In this study, a culture-dependent and high-resolution culture-independent approach (next generation sequencing) were used to identify endophytes in grapevine stems. In the culture-dependent approach, a total of 94 isolates were recovered from 84 of 144 healthy grapevine stem fragments (colonization rate = 58.3%). The study is unique as we used subsets of combined multi-gene regions to identify the endophytes to species level. Based on each multi-gene phylogenetic analysis, 28 species belong to 19 genera (Acremonium, Alternaria, Arthrinium, Ascorhizoctonia, Aspergillus, Aureobasidium, Bipolaris, Botryosphaeria, Botrytis, Chaetomium, Cladosporium, Curvularia, Hypoxylon, Lasiodiplodia, Mycosphaerella, Nigrospora, Penicillium, Phoma, Scopulariopsis) were identified. A higher number of culturable fungi were obtained from 13 year-old vines, followed by eight and three year-old vines. In the culture-independent approach, a fungal richness of 59 operational taxonomic units (OTU) was detected, being highest in 13 year-old grapevines, followed by eight and three years. Even though the cultivation approach detected lower fungal richness, the results related to stem are consistent for fungal community composition and richness. Comparison of the fungal taxa identified by the two approaches resulted in an overlap of 53% of the fungal genera. Due to interspecific variability of the sequences from NGS, in many cases the OTUs (even with the highly abundant ones) were only assignable to order, family or genus level. Incorporating multi-gene phylogenies we successfully identified many of the NGS derived OTUs with poor taxonomic information in reference databases to the genus or species levels. Hence, this study signifies the importance of applying both culture-dependent and culture-independent approaches to study the fungal endophytic community composition in Vitis vinifera. This principle could also be applied to other host species and ecosystem level studies.

The Dothideomycete Pseudocercospora fijiensis, previously Mycosphaerella fijiensis, is the causal agent of black Sigatoka, one of the most destructive diseases of bananas and plantains. Disease management depends on fungicide applications, with a major contribution from sterol demethylation-inhibitors (DMIs). The continued use of DMIs places considerable selection pressure on natural P. fijiensis populations, enabling the selection of novel genotypes with reduced sensitivity. The hitherto explanatory mechanism for this reduced sensitivity was the presence of non-synonymous point mutations in the target gene Pfcyp51, encoding the sterol 14α-demethylase enzyme. Here, we demonstrate a second mechanism involved in DMI sensitivity of P. fijiensis. We identified a 19-bp element in the wild-type (wt) Pfcyp51 promoter that concatenates in strains with reduced DMI sensitivity. A polymerase chain reaction (PCR) assay identified up to six Pfcyp51 promoter repeats in four field populations of P. fijiensis in Costa Rica. We used transformation experiments to swap the wt promoter of a sensitive field isolate with a promoter from a strain with reduced DMI sensitivity that comprised multiple insertions. Comparative in vivo phenotyping showed a functional and proportional up-regulation of Pfcyp51, which consequently decreased DMI sensitivity. Our data demonstrate that point mutations in the Pfcyp51 coding domain, as well as promoter inserts, contribute to the reduced DMI sensitivity of P. fijiensis. These results provide new insights into the importance of the appropriate use of DMIs and the need for the discovery of new molecules for black Sigatoka management.

Fungal endophytic species inhabiting the leaves of eucalypts are capable of utilising leaf sugars and can influence both plant growth and health. Endophytic fungal symbionts can use simple soluble sugars in leaves as their main carbon source. This study set out to determine the diversity and distribution of the endophytic filamentous fungal leaf community in the hybrid Eucalyptus urograndis due to its economic importance. The fungal leaf community was characterised using denaturing gradient electrophoresis (DGGE) and correlated with levels of leaf nutrients and sugars throughout plant development. Sequencing of DGGE bands revealed the presence of Basidiomycota and Ascomycota phyla. Fourteen species and three genera of filamentous fungi were identified, and the population structure was affected by the plant developmental stage. Levels of K, Cu, N and Mn influenced communities from the clonal garden, whereas leaves in the field had higher glucose, fructose and sucrose. Many fungi were found to be specific to a certain development stages: Diplomitoporus crustulinus, Podosphaera tridactyla and Aspergillus restrictus to the clonal garden stage; Chaetomella acutiseta and Ascotricha chartarum to the shading stage; Erratomyces patelii and Saxomyces sp. to the shading output stage; Lepidostroma sp. and Saxomyces sp. to the dispatch stage; and Mycosphaerella populicola to the field stage. Teratosphaeria toledana and Teratosphaeria acidotherma were found at more than one developmental stage. Cladosporium sp. and Rhodosporidium fluviale colonized and persisted in plants at the dispatch and field stages. This is the first report of P. tridactyla, A. restrictus, E. patelii, Saxomyces and Lepidostroma sp. as endophytes in eucalipt.

2 Pág. Instituto de Ciencias Forestales (ICIFOR), This work was supported by the Ministerio de Economía, Industria y Competitividad, Gobierno de España Project RTA 2017-00063-C04-03 INIA and funding from the Department of Economic Development, Sustainability and Environment (Basque Government).

Black leaf streak disease (BLSD) caused by Mycosphaerella fijiensis is considered the most destructive and costly foliar disease that affects bananas and plantains. In spite of some recent progress regarding the study of M. fijiensis-Musa spp. interaction, there is still limited information for this pathosystem. To gain insights into the molecular mechanisms behind the M. fijiensis-Musa spp. interaction, gene expression and biochemical analysis related with primary metabolism, methyl cycle, antioxidant and phenylpropanoid pathways were conducted. Early screening of the resistant cultivar (cv.) ‘Calcutta 4’ (Musa AA) and the susceptible cv. ‘Grande naine’ (Musa AAA) plants infected with M. fijiensis was effective at looking for defense-related genes. Quantitative PCR experiments showed up-regulation of Photosystem I reaction center subunit N chloroplastic-like (primary metabolism) and S-adenosyl- L-methionine synthetaste (methyl cycle) genes in the incompatible interaction, as well as down-regulation of the phenylpropanoid pathway genes in the susceptible cv. ‘Grande naine’ as main finding of this study. Improved knowledge concerning the M. fijiensis-Musa spp. interaction could help to establish innovative approaches for plant breeding programs against BLSD.

Fungi are the causal agents of many of the world's most serious plant diseases causing disastrous consequences for large-scale agricultural production. Pathogenicity genomic basis is complex in fungi as multicellular eukaryotic pathogens. Here, we report the genome sequence of C. sojina, and comparative genome analysis with plant pathogen members of the genus Mycosphaerella (Zymoseptoria. tritici (synonyms M. graminicola), M. pini, M. populorum and M. fijiensis - pathogens of wheat, pine, poplar and banana, respectively). Synteny or collinearity was limited between genomes of major Mycosphaerella pathogens. Comparative analysis with these related pathogen genomes indicated distinct genome-wide repeat organization features. It suggests repetitive elements might be responsible for considerable evolutionary genomic changes. These results reveal the background of genomic differences and similarities between Dothideomycete species. Wide diversity as well as conservation on genome features forms the potential genomic basis of the pathogen specialization, such as pathogenicity to woody vs. herbaceous hosts. Through comparative genome analysis among five Dothideomycete species, our results have shed light on the genome features of these related fungi species. It provides insight for understanding the genomic basis of fungal pathogenicity and disease resistance in the crop hosts.

Ramularia is a species-rich genus in the order Capnodiales (Dothideomycetes, Ascomycota) that includes numerous phytopathogenic taxa, several of which are economically important plant pathogens. In this study, six isolates of Ramularia were recovered from leaf spot symptoms on six herbaceous and woody plants from Guilan, East and West Azarbaijan provinces in the north and northwest of Iran. The isolates were studied by a polyphasic approach involving morphological and cultural data, and multi-gene phylogeny (ITS, TEF1-α, ACT, HIS, RPB2 and GAPDH). The isolates were grouped in three species clades of the R. eucalypti species complex. Of these, R. mali is recorded for the first time in Asia and R. glennii represents a new record for the mycobiota of Iran. Ramularia taleshina on Alnus subcordata is described as a new species. Ramularia taleshina is phylogenetically related to R. mali, but they can be differentiated by morphological and cultural characters as well as molecular data. Acalypha australis, Ficus carica and Platanus sp. are reported as new hosts of R. glennii, and Prunus cerasus and Vitis vinifera as new hosts of R. mali.

The aim of this research was to determine resistance reaction of 14 Musa genotypes against Mycosphaerella fijensis, causal agent of Black Sigatoka disease. Two experiments were conducted in laboratory and shadehause at Pichilingue research Station from the National Institute of Agricultural Research (INIAP), Ecuador. Genotypes considered were: Orito (AA), Guineo de jardin, Williams, Filipino, Gross Mitchel, Mulato and Morado, (AAA); Limeno, Maqueno, Dominico, Dominico-Harton, Dominico gigante, Dominico negro and Barraganete from the AAB genome. Two inoculation methods were used to asses’ resistance: a) in vitro inoculation over leaf fragments with a conidial suspension, and b) inoculation of eight weeks old seedlings with a mycelial suspension of the fungus. In the first case, the incubation period (IP) and the number of lesions at 14 and 20 days after inoculation (DDI) were measured. For in vitro trial, the incubation period (IP) and the number of leaf lesions 14 and 20 days after inoculation (DDI) were measured, and for seedlings, PI, period of symptoms evolution (TES) and time for disease development (TDE) were recorded. Statistically significant (p ≤ 0.05) differences were found for all variables. Cultivars Orito (AA) and Limeno (AAB) qualify as resistant while all the others were susceptible, though response to inoculation within the latter group showed a range of variability.

Leaf spot disease on black chokeberry (Aronia melanocarpa) was observed at several locations in Korea during 2014-2015. Leaf spots were distinct, scattered over the leaf surface and along the leaf border, subcircular to irregular and brown surrounded by a distinct dark color, and were expanded and coalesced into irregularly shaped lesions. Severely infected leaves became dry and fell off eventually. The causative agent was identified as Pseudocercospora pyricola. Morphological observations and phylogenetic analyses of multiple genes, including internal transcribed spacer, translation elongation factor 1-alpha, actin, and the large subunit ribosomal DNA were conducted. The pathogenicity test was conducted twice yielding similar results, fulfilling Koch's postulates. To our knowledge, this is the first report on P. pyricola infection of A. melanocarpa globally.

We used barcoded sequencing to analyze the eukaryotic population in the grape berries at different ripening states in four Australian vineyards. Furthermore, we used an innovative compositional data analysis for assessing the diversity of microbiome communities. The novelty was the introduction of log-ratio balances between the detected genera. Altogether, our results suggest that fungal communities were more impacted by the geographical origin of the Australian vineyards than grape variety and harvest time. Even if the most abundant genera were Aureobasidium and Mycosphaerella, they were ubiquitous to all samples and were not discriminative. In fact, the balances and the fungal community structure seemed to be greatly affected by changes of the genera Penicillium, Colletotrichum, Aspergillus, Rhodotorula, and Botrytis. These results were not evident from the comparison of relative abundance based on OTU counts alone, remarking the importance of the balance analysis for microbiome studies.

Grapevine is a pillar of the California state economy and agricultural identity. This study provides a comprehensive culture-independent microbiome analysis from the sap of grapevine overtime and in a context of a vascular disease. The vascular system plays a key role by transporting nutrient, water and signals throughout the plant. The negative pressure in the xylem conduits, and low oxygen and nutrient content of its sap make it a unique and underexplored microbial environment. We hypothesized that grapevine hosts in its sap, microbes that have a beneficial impact on plant health by protecting against pathogen attack and supporting key biological processes. To address this hypothesis, we chose a vineyard under high Pierce’s disease (PD). PD is caused by the xylem-dwelling pathogenic bacterium Xylella fastidiosa. We selected ten grapevines within this vineyard with a range of disease phenotypes, and monitored them over 2 growing seasons. We sampled each vines at key phenological stages (bloom, veraison, and post-harvest) and used an amplicon metagenomics approach to profile the bacterial (16S -V4) and fungal (ITS) communities of the sap. We identified a core microbiome of the sap composed of seven bacterial (Streptococcus, Micrococcus, Pseudomonas, Bacteroides, Massilia, Acinetobacter and Bacillus) and five fungal (Cladosporium, Mycosphaerella, Alternaria, Aureobasidium, and Filobasidium) taxa that were present throughout the growing season. Overall, the sap microbial makeup collected from canes was more similar to the root microbial profile. Alpha diversity metrics indicated a microbial enrichment at bloom and in vines with moderate PD severity suggesting a host-driven microbial response to environmental cues. Beta diversity metrics demonstrated that disease condition and plant phenology impacted microbial community profiles. Our study identified several potential taxonomic targets with antimicrobial and plant growth promoting capabilities that inhabit the grapevine sap and that should be further tested as potential biological control or biofertilizer agents.

Sixty-eight and eighty-six percent of monoascosporic isolates of Mycosphaerella fijiensis from two banana plantations in Costa Rica, in which benomyl was used for ≈10 years to control black Sigatoka, were resistant to benomyl in February and November 1994, respectively. No resistance to benomyl was detected in isolates collected during February 1994 from farms with no history of benomyl use that were located ≈50 km from the nearest banana plantations. Only 1% of isolates was resistant to benomyl in a sample taken during November 1994. In three additional banana farms where benomyl had not been used for 3 to 5 years before sampling, ben-omyl resistance persisted at a high frequency. Benomyl-resistant and -sensitive isolates were distributed equally throughout the range of isolate sensitivity to propiconazole, indicating no relationship between resistance to benomyl and lower sensitivity to propiconazole but double resistance to these two compounds. Five benomyl-resistant and five benomyl-sensitive isolates of M. fijiensis were inoculated to banana plants under greenhouse conditions. Benomyl-resistant isolates were more aggressive than benomyl-sensitive isolates, as determined by measures of disease severity, incubation time, and number of lesions at 40 days after inoculation.

Pisum sativum L. subsp. elatius (Steven ex M. Bieb.) Asch. & Graebn. is a wild pea species that is native to Bulgaria. It readily crosses to the cultivated pea species P. sativum subsp. sativum. Field pea is an important component in the crop rotation system of the northeast region of Bulgaria. Little is known or published on the diseases of wild Pisum subspecies. In June 1997, brown to reddish brown, irregularly shaped lesions 5 to 10 mm in diameter were found on the leaves and stems of P. sativum subsp. elatius growing under native conditions in the low growing vegetation in a mixed forest habitat on the Black Sea coast at Albena, Bulgaria (43°22′26″N; 28°05′02″E) at an elevation of about 50 m. Black pycnidia were observed within lesions and contained hyaline, primarily two-celled conidia that measured 7 to 17 × 3 to 5 μm. On artificially inoculated pea stem pieces incubated on 2% water agar (WA) at 22 to 24°C for 28 days, pseudothecia developed with hyaline, two-celled ascospores constricted at the septum and measuring 12 to 17 × 4 to 7 μm. Black chlamydospores produced singly or in chains also formed in infected foliar tissues and on potato dextrose agar (PDA) and WA. Isolations were made from the lesions on pea tissue onto WA and PDA after disinfesting in 0.25% NaOCl for 5 min. Koch's postulates were fulfilled by inoculating the foliage of P. sativum subsp. sativum cvs. Dark Skin Perfection and Sounder and P. sativum subsp. elatius (W6-20047), and reisolating the fungus from lesions that developed on the inoculated leaves and stems. The wild Pisum fungus was identified as Mycosphaerella pinodes (Berk. & Blox.) Vestergr. based on cultural and morphological characteristics (2), pathogenicity tests, and by comparing random amplified polymorphic DNA (RAPD) markers with those of American Type Culture Collection (ATCC) isolates 201628 to 201633 of M. pinodes. The fungus was identified as a pathogen of cultivated peas in Bulgaria by Kovachevsky and Hristov (1) in 1949. This is the first report of M. pinodes infecting P. sativum subsp. elatius in Bulgaria and other countries where P. sativum subsp. elatius is a native plant species. References: (1) I. H. Kovachevsky and A. Hristov. 1949. Bulgarian Acad. Sci., Scientific-Popular Ser. 10. (2) E. Punithalingam and P. Holliday. 1972. CMI Descript. of Pathog. Fungi and Bacteria, no. 340. Commonwealth Mycol. Institute, Kew, England.

Infection studies with Mycosphaerella fijiensis, causal agent of black Sigatoka disease of banana (Musa AAA), demonstrated that the abaxial leaf surface is the primary infection site. Inoculation of banana plants with M. fijiensis ascospores on the abaxial surface of young leaves resulted in disease symptoms in 100% of the leaves inoculated within 18 to 30 days; whereas only 5% of the leaves inoculated on the adaxial surface showed black Sigatoka symptoms within 10 weeks. Disease symptoms appeared more rapidly on the new, emerging leaves than on the first and second fully expanded leaves. Application of chlorothalonil (1.08 kg a.i. ha-1) to the abaxial surface of emerging leaves resulted in 99 to 100% disease control in the treated area. When the emerging leaf was not sprayed until fully expanded, disease control was reduced to 76 to 80%. Application of chlorothalonil to the adaxial surface of banana leaves had little or no impact on disease control. Chlorothalonil arrested hyphal growth when applied to banana leaves after ascospores had already germinated and reduced the rate of lesion expansion when applied to the abaxial leaf surface after symptom appearance. Chlorothalonil was less effective than systemic fungicides in reducing production of M. fijiensis pseudothecia in infected tissue. When systemic and protectant fungicides were applied to infected leaf tissue, none of the fungicides affected the viability of ascospores that were discharged from pseudothecia produced in that tissue. For successful control of black Sigatoka with chlorothalonil, deposition of the fungicide on the abaxial leaf surface is essential.

Black Sigatoka, which is also known as black leaf streak, is caused by Mycosphaerella fijiensis (anamorph Pseudocercospora [formerly Paracercospora) fijiensis]). It is the most important disease of commercially produced banana (Musa spp.) and also has a major impact on production for local consumption. Although the disease occurs throughout the humid tropics, it has been reported in the Caribbean from only Cuba, Hispaniola, and Jamaica (1). In February 2004, black Sigatoka was observed at two isolated and widely separated sites on Grand Bahama island (26.7°N, 78.5°W and 26.7°N, 78°W) on cvs. Silk AAB and Williams AAA, and a French Horn AAB plantain. Symptoms included wet, dark brown streaks on the adaxial leaf surface, 1 to 2 × 10 mm, with chlorotic haloes. Lesions enlarged to 5 × 20 mm and developed tan, necrotic centers; large, blackened, water-soaked areas that resulted from the coalescence of streaks were rare. The disease was confirmed by observing the following characteristics of P. fijiensis in necrotic lesions on preserved leaf specimens: simple conidiophores with a broadened base and one to several septa, straight to variously bent cercosporoid conidia as much as 100 μm long with two to several septa, and a conspicuously thickened scar at the base. Both plantings were several years old and new planting material that could have been infested with the pathogen had not been introduced since their establishment. Symptoms were not severe and were distributed sporadically in both locations. The disease was not observed at the only other large planting of banana on the island (26.6°N, 78.6°W). The sporadic and apparently new infestations of two of three banana plantings on the island suggest that the pathogen may have arrived recently via natural means, possibly from neighboring Florida (2). In contrast, black Sigatoka appears to have spread to other islands in the Caribbean via infested propagation materials (1). To my knowledge, this is the first report of black Sigatoka in the Bahamas, and with a previous report from Bhutan (1), represents the northernmost spread of this important disease. References: (1) J. Carlier et al. Pages 37–79 in: Diseases of Banana, Abacá and Enset. D. R. Jones, ed. CABI Publishing. Wallingford, UK, 2000. (2) R. C. Ploetz and X. Mourichon. Plant Dis. 83:300, 1999.

Sooty blotch and flyspeck (SBFS), a disease complex comprised of as many as 30 putative species of fungi, occurs on the cuticle of pome fruits in moist production regions worldwide, inciting cosmetic damage that causes significant economic losses (1). Chinese hawthorn (Crataegus pinnatifida Bge.) is an economically important tree species in China. Its fruit are sold fresh or dried and are used as a culinary spice as well as an ingredient in Chinese traditional medicine. In October of 2007, Chinese hawthorn fruit exhibiting SBFS signs were sampled from supermarkets in Yangling, Shaanxi Province and Luoyang, Henan Province, China. Thalli directly from the hawthorn fruit were transferred onto potato dextrose agar (PDA) slants under a dissecting microscope and cultured at 22 ± 1°C in darkness. DNA was extracted from pure isolates and the internal transcribed spacer (ITS) region of the nuclear ribosomal DNA (nrDNA) was amplified and sequenced using primers ITS-1F and ITS4 (3). Phylogenetic analysis of the ITS sequences revealed that the 35 isolates generated in this study included five species in three genera: Dissoconium sp. (18 isolates), Mycosphaerella sp. (5 isolates), and Peltaster sp. 1 (4 isolates), Peltaster sp. 2 (4 isolates), and Peltaster sp. 3 (4 isolates). To fulfill Koch's postulates and verify that these fungi could also infest apple fruit, two representative isolates of each putative species were inoculated onto mature intact hawthorn and apple (cv. Fuji) fruit that had been surface disinfested with 75% ethanol and allowed to dry. Inoculum was prepared by comminuting 1-month-old cultures growing on PDA into a suspension of mycelial fragments and conidia (105 to ~106 CFU/ml) in a blender with sterile deionized water (SDW). Each isolate was inoculated on three hawthorn and three apple fruit by using cotton swabs. As controls, two surface-disinfested hawthorn and apple fruit were swabbed with SDW. After the inoculated hawthorn and apple fruit had been incubated in a moist chamber at 22 ± 1°C for 1 month, all inoculated hawthorn and apple fruit exhibited SBFS signs similar to those of the original colonies on hawthorn fruit, but the controls did not. Reservoir hosts have been inferred to play an important role in SBFS by providing the fungi with overwintering habitat and inoculum for infestations on apple. Many reservoir hosts have been reported in the United States and Japan (2). To our knowledge, this is the first report of fungi in the SBFS complex on hawthorn fruit and the first confirmation that fungi growing on hawthorn fruit can produce SBFS signs on apple fruit. These results identify hawthorn as a potential inoculum source for SBFS in apple orchards. References: (1) J. C. Batzer et al. Mycologia 97:1283, 2005. (2) K. Hemnani et al. Phytopathology 98(suppl):S66, 2008. (3) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

Mycosphaerella fijiensis Morelet (anamorph Pseudocercospora fijiensis Morelet), the causal agent of black Sigatoka disease of banana, is considered to be the greatest economical threat for export-banana cultivation throughout the world because most cultivars are highly susceptible. The disease has a worldwide distribution throughout the humid tropical regions, but was still absent in some Caribbean islands hitherto. In Martinique Island, an intensive survey has been conducted by the plant protection service and the Fédération Régionale de Défense Contre les Organismes Nuisibles (FREDON) since April 2008 to detect as early as possible any outbreak of infection by M. fijiensis. In September 2010, typical symptoms of black Sigatoka were observed in a plantain crop located in Ducos Municipality (14°35.702′N, 60°58.221′W) in the west-central area of the island. Typical early symptoms were 1- to 4-mm long brown streaks on the abaxial leaf surface. The presence of the disease was further confirmed by the in situ observation of microscopic features of the anamorphic form of the pathogen (3). Typical pale brown, straight or slightly geniculate conidiophores were observed occurring singly or in little groups without any stroma, with a thickened wall at the conidial scars. Conidia were hyaline to pale olive, straight or slightly curved, with one to eight septa, and a conspicuous scar at the basal cell. The diagnosis was confirmed by real-time PCR targeting M. fijiensis-specific regions within the β-tubulin gene (1). Positive results were consistently obtained with DNA extracted from infected banana tissue samples, and the identity of the amplicon was confirmed by sequencing (Accession No. HQ412771) and comparison with reference sequences deposited on GenBank. After this first finding, the survey was intensified and black Sigatoka symptoms were also observed in several other locations on the island, affecting a large range of susceptible cultivars (Grande Naine, French, and Figue Sucrée), and in plantations, backyards, and private gardens. The presence of the fungus in the samples was confirmed by PCR analysis of DNA extracted from symptomatic leaves with a M. fijiensis-specific ITS-based primer pair (2). The pathogen may have been introduced into Martinique by ascospores, from islands where black Sigatoka is present, that were blown by continuous southerly winds over a 2-week period in August 2010 that was immediately followed by heavy rains that favor disease development. To our knowledge, this is the first report of M. fijiensis on Martinique Island, showing that the disease is still spreading northward in this region of the Caribbean. References: (1) M. Arzanlou et al. Phytopathology 97:1112, 2007. (2) J. Henderson et al. Page 59 in: Mycosphaerella Leaf Spot Disease of Bananas: Present Status and Outlook. L. Jacome et al., eds. International Network for the Improvement of Banana and Plantain (INIBAP), Montpellier, France. 2003. (3) M. F. Zapater et al. Fruits 63:389, 2008.

Black spot is a major disease of field pea (Pisum sativum L.) production across southern Australia. Known causal agents in Australia include one or more of Mycosphaerella pinodes (Berk. & Bloxam) Vestergr., Phoma medicaginis var. pinodella (L.K. Jones), Ascochyta pisi Lib., or P. koolunga (Davidson, Hartley, Priest, Krysinska-Kaczmarek, Herdina, McKay & Scott) (2), but other pathogens may also be associated with black spot symptoms. Black spot generally occurs on most plants and in most pea fields in Western Australia (W.A.), and during earlier winter/spring surveys of blackspot pathogens, some isolates were tentatively allocated to P. medicaginis var. pinodella despite different cultural characteristics on potato dextrose agar (PDA). Recently, single-spore isolations of a single culture each from an infested pea crop at Medina, Moora, and Mt. Barker in W.A. were made onto PDA. A PCR-based assay with TW81 and AB28 primers was used to amplify from the ITS-5.8S rDNA region. Purified DNA products were sequenced for the three isolates and then BLASTn was used to compare sequences with those in GenBank. Our sequences (GenBank Accession Nos. JN37743, JN377439, and JN377438) had 100% nucleotide identity with P. exigua Desm. var. exigua accessions (GI13385450, GI169894028, and GI189163921), an earlier synonym of what is now known as Boeremia exigua var. exigua ([Desm.] Aveskamp, Gruyter & Verkley) (1). Davidson et al. (2) used the same primers to identify P. koolunga, but none of our isolates were P. koolunga. A suspension of 107 conidia ml–1 of each representative isolate was inoculated onto foliage of 15-day-old field pea cv. Dundale plants and maintained at >90% relative humidity for 72 h postinoculation. Control plants inoculated with just water remained symptomless. Brown lesions were evident by 8 to 10 days postinoculation and mostly 1 to 3 mm in diameter. B. exigua var. exigua was readily reisolated from infected leaves. Isolates have been lodged in the W.A. Culture Collection Herbarium maintained at the Department of Agriculture and Food W.A. (Accession Nos. WAC13500, WAC13502, and WAC13501 from Medina, Moora, and Mt. Barker, respectively). Outside Australia, its synonym P. exigua var. exigua is a known pathogen of field pea (4), other legumes including common bean (Phaseolus vulgaris L.) (4) and soybean (Glycine max [L.] Merr.) (3), and is known to produce phytotoxic cytochalasins. In eastern Australia, P. exigua var. exigua has been reported on common bean (1930s and 1950s), phasey bean (Macroptilium lathyroides [L.] Urb.) and siratro (M. atropurpureum (DC.) Urb.) (1950s and 1960s), mung bean (Vigna radiata [L.] Wilczek.) (1960s), ramie (Boehmeria nivea [L.] Gaudich.) (1939), potato (Solanum tuberosum L.) (1980s), and pyrethrum (Tanacetum cinerariifolium [Trevir.] Schultz Bip.) (2004 and 2007) (Australian Plant Pest Database). To our knowledge, this the first report of B. exigua var. exigua on field pea in Australia, and because of its potential to be a significant pathogen on field pea, warrants further evaluation. References: (1) M. M. Aveskamp et al. Stud. Mycol. 65:1, 2010. (2) J. A. Davidson et al. Mycologia 101:120, 2009. (3) L. Irinyi et al. Mycol. Res. 113:249, 2009. (4) J. Marcinkowska. Biul. Inst. Hod. Aklim. Rosl. 190:169, 1994.

A thorough assessment of the distribution of Mycosphaerella spp. associated with banana in Minas Gerais State, Brazil, was conducted after Mycosphaerella fijiensis was first reported to occur in this region in 2005. From 2009 to 2011, 80 fields located in 20 municipalities including the same fields where the disease was first reported were sampled. A total of 800 samples of leaf tissue with symptoms similar to those of yellow or black Sigatoka diseases were examined, and 239 isolates were obtained. The identification of the fungi was based on morphological characters combined with DNA sequences obtained after amplification with species-specific primers and phylogeny inferred from the internal transcribed spacer region of Mycosphaerella strains from banana. All 239 isolates were identified as Mycosphaerella musicola. The absence of M. fijiensis in the samples may have been due to misidentification of M. fijiensis or the displacement of M. fijiensis by M. musicola. It is now apparent that yellow Sigatoka caused by M. musicola is the prevailing leaf spot disease of bananas in Minas Gerais State and that regulatory/legislative control measures need to be revised based on our findings.

Sigatoka leaf streaks caused by Mycosphaerella spp. are the most destructive fungal diseases of bananas and plantains throughout the world. The disease is not well documented so far in Ethiopia though it is so calamitous in east and central Africa. Detailed assessment accompanied by infected samples collection for identification was carried out in farmers’ fields, research plots and large-scale banana plantations. The results showed black Sigatoka leaf streak is causing extensive damage with pronounced incidence (>75%) and severity (>50%) in southwest Ethiopia. It is also common on enset (Ensete ventricosum). Mycosphaerella fijiensis is largely identified from symptomatic banana leaves and confirmed with pathogenicity tests. The incidence and severity varied significantly (P 60%). This is the first record of black Sigatoka leaf streak associated with Mycosphaerella fijiensis on banana and enset in Ethiopia, thus untiring efforts should be directed to manage Sigatoka disease in Ethiopia.

The objective of this study was to validate the use of banana leaf sections as a technique to study the molecular interaction between Mycosphaerella fijiensis and Musa spp. without the interference of biotic and abiotic factors that commonly occur under field conditions. The growth of M. fijiensis in banana leaf sections was evaluated and compared with the growth of the fungus in leaves under field conditions. Growth comparison was carried out through the absolute quantification by real-time PCR of a segment of the β-tubulin gene of M. fijiensis. Validation of the banana leaf sections technique consisted in monitoring M. fijiensis MfAvr4 gene expression and its relative quantification by real-time PCR in banana leaf sections. With this technique, it was shown that the growth of M. fijiensis and MfAvr4 gene expression were similar to those observed in infected leaves in the field. These quantitative real-time PCR results support the suitability of using banana leaf sections for molecular studies of gene expression in M. fijiensis-Musa spp. interactions.

Two hundred and sixty-one bacterial isolates associated with banana tree roots in organic systems were isolated from 19 farms located in four different provinces of the Dominican Republic. The isolates were analysed by means of ARDRA plus RAPD, and as a consequence 114 of them were selected for identification by means of complete 16S rRNA sequencing and phylogenetic reconstruction. The 114 isolates belonged to 20 different genera, with Bacillus , Pseudomonas , Enterobacter and Stenotrophomonas the prevailing genera. Of these, 65 isolates showed more than 99.5% similarity with a type strain, and they were assigned to 34 different species from 16 genera; 29 isolates could constitute new species and the remaining 20 isolates belonged to groups containing more than one species with identical 16S rRNA genes, and therefore they could not be assigned to any species. This result showed a higher number of bacterial taxa associated with banana tree roots than previously described. Additionally, we found seven bacterial species with significant in vitro plant growth promoting (PGP) activity, which had not been previously described as PGP bacteria in any crop. Field trials with isolates pre-selected based on their in vitro PGP activity showed that one strain of the species Pseudomonas plecoglossicida improved fruit yield and controlled the incidence of the disease black sigatoka caused by Mycosphaerella fijiensis . This activity was tentatively attributed to induced systemic resistance mechanisms. Bacterial diversity was analysed among the 261 isolates based on the Shannon index of diversity (H), calculated from the ARDRA profiles. Interestingly, the majority of the bacterial diversity was found within farms (86% of the total), being higher than the bacterial diversity between farms (14%). Moreover, the differences in the average H Index between provinces were very low. Consequently the biodiversity of the bacterial communities was little influenced by the soil characteristics. These results could work in favour of the efficient adaptation of the bacterial strains selected for use as plant probiotics in a range of soils in the region analysed.

Banana black leaf streak, caused by Mycosphaerella fijiensis M. Morelet, is a primary phytosanitary concern in export of this fruit around the world. To develop improved cultivars resistant to this disease, an understanding of host response to infection is necessary. In this study, we obtained expression data on 14,872 genes by microarray analysis in the resistant genotype Musa acuminata subsp. burmannicoides ‘Calcutta 4’ after inoculation with Mycosphaerella fijiensis. From these data, 16 genes were analyzed as potential reference genes and 12 genes were identified as potential early indicators of the onset of the host defense response. Subsequently, these genes were analyzed by quantitative reverse-transcription polymerase chain reaction in susceptible ‘Williams’ and resistant Calcutta 4. The 18S and 26S ribosomal subunit genes in both cultivars showed the best characteristics as reference genes. In all, 5 of the 12 defense genes expressed shortly after infection (peroxidase, pathogenesis-related [PR]-4, PR-10, phenylalanine ammonia-liase, and disease resistance response 1) showed overexpression in Calcutta 4 between 6 and 24 h after inoculation as opposed to Williams, which did not show overexpression after 144 h. Early induction of defense-related genes could be a key component of the resistance of the Calcutta 4 genotype against M. fijiensis. In addition, these five genes could be used as indicators of the activation of defense responses in the interaction between banana and M. fijiensis.

Ramularia is a species-rich genus that harbours plant pathogens responsible for yield losses to many important crops, including barley, sugar beet and strawberry. Species of Ramularia are hyphomycetes with hyaline conidiophores and conidia with distinct, thickened, darkened, refractive conidiogenous loci and conidial hila, and Mycosphaerella sexual morphs. Because of its simple morphology and general lack of DNA data in public databases, several allied genera are frequently confused with Ramularia. In order to improve the delimitation of Ramularia from allied genera and the circumscription of species within the genus Ramularia, a polyphasic approach based on multilocus DNA sequences, morphological and cultural data were used in this study. A total of 420 isolates belonging to Ramularia and allied genera were targeted for the amplification and sequencing of six partial genes. Although Ramularia and Ramulariopsis proved to be monophyletic, Cercosporella and Pseudocercosporella were polyphyletic. Phacellium isolates clustered within the Ramularia clade and the genus is thus tentatively reduced to synonymy under Ramularia. Cercosporella and Pseudocercosporella isolates that were not congeneric with the ex-type strains of the type species of those genera were assigned to existing genera or to the newly introduced genera Teratoramularia and Xenoramularia, respectively. Teratoramularia is a genus with ramularia-like morphology belonging to the Teratosphaeriaceae, and Xenoramularia was introduced to accommodate hyphomycetous species closely related to Zymoseptoria. The genera Apseudocercosporella, Epicoleosporium, Filiella, Fusidiella, Neopseudocercosporella, and Mycosphaerelloides were also newly introduced to accommodate species non-congeneric with their purported types. A total of nine new combinations and 24 new species were introduced in this study.

The introduction and establishment of non-native plant pathogens into new areas can result in severe outbreaks. Septoria leaf spot and canker caused by Sphaerulina musiva is one of the most damaging poplar diseases in northeastern and north-central North America. Stem and branch cankers can be devastating on susceptible trees, leading to tree death and reduced biomass in commercial plantations. In the Pacific Northwest region of North America, the first report of the disease was made in 2006 in the Fraser Valley of British Columbia (BC), Canada. To investigate the incidence and distribution of S. musiva from its point of introduction into BC, five plantations of Populus trichocarpa (black cottonwood), 500 P. trichocarpa trees from natural populations, and 23 plantations of hybrid poplars were surveyed by using real-time PCR assays targeting S. musiva and its native sister species, S. populicola. Our survey suggests a strong anthropogenic signature to the emergence of the non-native S. musiva. Detection frequency of S. musiva was high in hybrid poplar plantations (116 trees infected, 54.2 % of the sampled trees), while detection of the native S. populicola was limited to 13.1 % (22 trees infected). By contrast, in natural stands of P. trichocarpa, less than 2 % of the trees were positive for S. musiva (7 trees) while ~75 % were positive for S. populicola (433 trees). All the S. musiva detections in natural stands of the native P. trichocarpa were from trees located in the vicinity (

Mycosphaerella blight, caused by Mycosphaerella pinodes, is a destructive disease of field pea that is managed using foliar fungicides. Strobilurin fungicides have been used in western Canada for disease management since 2003. To assess the baseline sensitivities of M. pinodes isolates to the strobilurin fungicide pyraclostrobin, the effective concentration to reduce mycelial growth by 50% (EC50) was determined for 70 isolates collected prior to 2003 from Alberta, Saskatchewan, North Dakota, and Washington State. Each of these isolates was sensitive to pyraclostrobin, with EC50 values ranging from 0.03 to 0.29 mg liter−1. The pyraclostrobin concentrations required to reduce conidia germination by 50% was lower, ranging from 0.008 to 0.041 mg liter−1. In all, 324 isolates collected in 2010 and 2011 were tested for high levels of insensitivity by examining mycelial growth using a discriminatory dose of 5 mg liter−1. Nineteen isolates were highly insensitive to pyraclostrobin, with EC50 values of 80 to 216 mg liter−1. Conidia of these isolates germinated when exposed to a discriminatory dose of 0.1 mg liter−1. Insensitive isolates infected field pea plants treated with pyraclostrobin but sensitive isolates did not. The identification of insensitive isolates indicates that insensitivity may be emerging in the pathogen population.

The critical revision of 59 Asteromella species occurring in Poland is presented, based primarily on specimens from Poland, as well as selected herbarial materials from France, Germany, Italy, Latvia, Lithuania, Romania, Slovakia, Switzerland and Ukraine. Some exsiccata, including types of Asteromella carlinae Petr., Asteromella ludwigii Petr., Asteromella ovata Thüm., Asteromella petasitidis Petr., Depazea agrimoniae Lasch, Mycosphaerella agrimoniae Syd., Phyllosticta borszczowii Thüm., Phyllosticta cicutae Lind, Phyllosticta eupatoriicola Kabát & Bubák, Phyllosticta pleurospermi Died., Phyllosticta salicina Kabát & Bubák, Phyllosticta senecionis-nemorensis Săvul. & Sandu, Phyllosticta wandae Namysł. were also studied. Each species is accompanied by the information pertaining to host spectrum, morphology of conidiomata, conidiophores, conidiogenous cells and conidia, distribution in Poland and globally, as well as information on synanamorphs and teleomorph, if present.Two species, Asteromella moeszii Ruszkiewicz-Michalska & Mułenko spec. nov. on Pulmonaria obscura and Asteromella rupprechtii Ruszkiewicz-Michalska spec. nov. on Agrimonia eupatoria are described, based on Polish specimens. A new name, Asteromella huubii Ruszkiewicz-Michalska nom. nov., is proposed to replace Asteromella angelicae (Sacc.) Moesz ex Bat. & Peres. Nine Phyllosticta and two Depazea species were redisposed into Asteromella: Asteromella acetosae (Sacc.) Ruszkiewicz-Michalska, comb. nov., Asteromella adoxicola (Lasch) Ruszkiewicz-Michalska, comb. nov., Asteromella alnicola (C. Massal.) Ruszkiewicz-Michalska, comb. nov., Asteromella bacilloides (Dominik) Ruszkiewicz-Michalska, comb. nov., Asteromella prunellae (Ellis & Everh.) Ruszkiewicz-Michalska, comb. nov., Asteromella garbowskii (Gucevič) Ruszkiewicz-Michalska, comb. nov., Asteromella lysimachiae (Allesch.) Ruszkiewicz-Michalska, comb. nov., Asteromella populina (Fuckel) Ruszkiewicz-Michalska, comb. nov., Asteromella salicina (Kabát & Bubák) Ruszkiewicz-Michalska, comb. nov. Neotype of Asteromella bacilloides and a lectotype of Asteromella adoxicola are designated.Nine species reported in the literature are not confirmed to occur in Poland; this includes two species that need to be recollected [Asteromella scabiosae (Kalymb.) Vanev & Aa and Asteromella mali (Briard) Boerema & Dorenb.)], as dried specimens are scarce and deficient. Affinity of Asteromella confusa (Bubák) Petr. to Asteromella vs. Phoma is briefly disputed. New records and new data on the distribution of Asteromella species in Latvia, Poland, Slovakia, Switzerland and Ukraine are also provided. Three species are reported as new to Polish funga: Asteromella prunellae, Asteromella melampyrina and Asteromella moeszii.

Heliconia rostrata (false bird of paradise, Heliconiaceae) is native to South America but is an important herbaceous perennial ornamental plant in India and globally. In December 2016, a foliar blight was observed on six ten-month-old H.…

Phenylphenalenones, polycyclic aromatic natural products from some monocotyledonous plants, are known as phytoalexins in banana (Musa spp.). In this study, (1) H nuclear magnetic resonance (NMR)-based metabolomics along with liquid chromatography and mass spectrometry were used to explore the chemical responses of the susceptible 'Williams' and the resistant 'Khai Thong Ruang' Musa varieties to the ascomycete fungus Mycosphaerella fijiensis, the agent of the black leaf Sigatoka disease. Principal component analysis discriminated strongly between infected and non-infected plant tissue, mainly because of specialized metabolism induced in response to the fungus. Phenylphenalenones are among the major induced compounds, and the resistance level of the plants was correlated with the progress of the disease. However, a virulent strain of M. fijiensis was able to overcome plant resistance by converting phenylphenalenones to sulfate conjugates. Here, we report the first metabolic detoxification of fungitoxic phenylphenalenones to evade the chemical defence of Musa plants.

Black leaf streak disease, also known as black Sigatoka, causes dramatic losses in production of banana and plantains fruits. The disease is caused by the pathogenic fungus Mycosphaerella fijiensis (anamorph Pseudocercospora fijiensis; Mycosphaerellaceae). Genetic transformation of M. fijiensis would allow a better understanding of molecular basis of pathogenicity and design novel approaches to control the infection caused by this pathogen. However, transformation of this fungus has not been easy. We report here a protocol for genetic transformation of M. fijiensis employing underwater shock waves and intact conidia. The recombinant strains recovered showed genetic stability over >10 generations. The frequency of transformation obtained was between 75 and 150 times higher than the efficiency reported in the only article published on transformation of M. fijiensis using spheroplasts. This improvement allowed the use of a thousand times less cells than the amount employed before, avoiding the need for cumbersome successive batch cultures. Our protocol is simple, highly efficient, fast and reproducible and together with the available genomes of M. fijiensis and Musa acuminata, it offers new possibilities to study the diverse mechanisms of pathogenesis of the fungus.

Endophytes are microorganisms that live inside plant tissues throughout its life cycle and during certain phases of development. The endophyte–host relationships can provide benefits to the host, protecting it against attack by insects and diseases. Several studies have demonstrated the diversity of endophytes from Coffea arabica, but few studies in varieties of organic crops. Thus, the objective in this study was to corroborate these reports with knowledge of the endophytic fungi communities in an organic variety of C. arabica L. cultivar IAPAR-59. We identified the endophytic fungi by molecular methods using the ITS1-5.8S-ITS2 region of rDNA and phylogenetic analyses. In the antagonist activity tests, the endophytes were tested against phytopathogens with the evaluation of the kind of interactions between them. Analyses demonstrated a diversity of genera, including: Colletotrichum, Trichoderma, Schizophyllum, Mycosphaerella, Cladosporium, and Cercospora, as well as the first record of the genus Ophiognomonia in C. arabica. The antagonist activity showed reduced growth of the phytopathogenic fungi Glomerella sp., Colletotrichum sp. and Sclerotinia sclerotiorum. The results obtained in this work, with the identification for the first time, of a highly diverse isolated endophytic of the species Ophiognomonia sp. in the coffee plants, is the second report of the detection of these fungi in Brazil. Also, the detection of different isolates with the ability to antagonise pathogens, emphasises the importance of further research, involving the isolation, identification and exploration of endophytes of other genetic varieties of coffee, obtained by breeding programs of this important crop in Brazil.

Pygmy waterlily (Nymphaea tetragona, Nymphaeaceae) is a perennial aquatic herb with floating leaves and beautiful flowers. Leaf spot on pygmy waterlilies appeared in 2009 at several locations in Korea, e.g., Suwon in 2009, Yangpyeong in 2011, and Seoul in 2014. The leaf spots were circular to irregular, small, and brown in the center with a dark brown margin. The spots later became milky white. The causative agent of the leaf spot was identified as Pseudocercospora nymphaeacea. Morphological observations and multigene phylogenetic analyses of the internal transcribed spacer (ITS), the partial translation elongation factor 1-alpha (TEF-1α), and actin (ACT) regions are provided. The pathogenicity test was conducted twice with similar results, which fulfilled Koch’s postulates. To our knowledge, this is the first report on P. nymphaeacea infection of N. tetragona.

BACKGROUND Evaluation of 4-phenylphenalenones and structural analogues against the fungal pathogen Mycosphaerella fijiensis (causal agent of black sigatoka disease in bananas) under light-controlled conditions uncovered some key structural features for the design of photodynamic compounds. RESULTS Structure–activity relationship analysis revealed the importance of a chromophoric aryl-ketone and a steroidomimetic structural motif in the activity of the assayed compounds. The results pointed to 1,2-dihydro-3H-naphtho[2′,1′:3,4]cyclohepta[1,2-b]furan-3-one, which displayed an activity in the range of propiconazole but with photodynamic behaviour. CONCLUSION The present work demonstrates that 1,2-dihydro-3H-naphtho[2′,1′:3,4]cyclohepta[1,2-b]heterocyclic-3-one derivatives can be used as potential lead compounds for the development of fungicides, relying on a dual mode of action. © 2015 Society of Chemical Industry

Wood packing materials (WPM) are important vectors of invasive xylophagous insects and pathogenic and decomposer wood fungi. The International Plant Protection Convention introduced the International Standards for Phytosanitary Measures No. 15 (ISPM No. 15) to regulate the development of treatments to sanitize WPM and prevent the introduction and movement of forest pests. Dielectric heating (e.g., microwave irradiation) has recently been included as an accepted treatment. In this study, the efficacy of microwave irradiation was tested on Monochamus scutellatus larvae and on four different pathogenic fungi, Gremmeniella abietina, Heterobasidion annosum, Chondrostereum purpureum, and Mycosphaerella populorum, five species of economic significance in Quebec, in both jack pine and trembling aspen. We explored different temperature/time combinations on each species in order to accumulate data on the treatment. We irradiated M. scutellatus larvae at 56, 61, and 66 °C for 1–3 min and the four fungal species at 50, 55, 60, 65, 70, 75, and 90 °C for 0.5, 1, or 2 min. Fungi were tested at a wider range of temperatures to account for possible higher variation of resistance between species. We obtained 100% mortality in larvae treated at 56 °C for 2 min and at 61 °C for 1 min. The fungi species were much more resistant to the treatment. G. abietina was eliminated at 75 °C/0.5 min, H. annosum at 90 °C/1 min, M. populorum at 90 °C/2 min, and C. purpureum was still present at the highest temperature/time combination used. We demonstrated the capacity of microwave irradiation to kill the larvae with similar parameters as IPPC guidelines (60 °C for 1 min), though lethal temperatures for the fungi were very high. As the current ISPM No. 15 standard for microwave irradiation was insufficient to kill all tested fungal species, more work should be done on determining optimal combinations for the greatest number of species. Future studies should test a wider range of treatment times and expand trials to include more insect and fungal species to determine which temperature/time combination will allow us to keep both values as low as possible while assuring complete prevention of adult insect emergence and fungal re-growth.

The genus Cercospora includes many important plant pathogenic fungi associated with leaf spot diseases on a wide range of hosts. The mainland of Iran covers various climatic regions with a great biodiversity of vascular plants, and a correspondingly high diversity of cercosporoid fungi. However, most of the cercosporoid species found to date have been identified on the basis of morphological characteristics and there are no cultures that support these identifications. In this study the Consolidated Species Concept was applied to differentiate Cercospora species collected from Iran. A total of 161 Cercospora isolates recovered from 74 host species in northern Iran were studied by molecular phylogenetic analysis. Our results revealed a rich diversity of Cercospora species in northern Iran. Twenty species were identified based on sequence data of five genomic loci (ITS, TEF1-α, actin, calmodulin and histone H3), host, cultural and morphological data. Six novel species, viz. C. convolvulicola, C. conyzae-canadensis, C. cylindracea, C. iranica, C. pseudochenopodii and C. sorghicola, are introduced. The most common taxon was Cercospora cf. flagellaris, which remains an unresolved species complex with a wide host range. New hosts were recorded for previously known Cercospora species, including C. apii, C. armoraciae, C. beticola, C. cf. richardiicola, C. rumicis, Cercospora sp. G and C. zebrina.

Fallopia japonica, commonly known as Japanese knotweed, is an increasingly serious invasive alien weed in the UK and large parts of mainland Europe, as well as in North America. There is an urgent need to include classical biological control (CBC) into any integrated pest management strategy. The leaf-spot pathogen Mycosphaerella polygoni-cuspidati, a coevolved natural enemy of F. japonica present throughout its native Japanese range, is considered to have high potential as a CBC agent. In this study, the disease development of M. polygoni-cuspidati in the field and the optimum infection parameters under controlled conditions were investigated to elucidate the pathogen’s potential biocontrol efficacy against Japanese knotweed. Field observation in Japan showed that M. polygoni-cuspidati caused severe damage to its host plant. When sentinel knotweed plants from the UK were placed amongst naturally-infected field populations of F. japonica, disease incidence and severity were highest in July when monthly precipitation was also highest. In greenhouse inoculation tests, F. japonica was shown to be most susceptible at the young leaf stage (7–12 days after opening). Disease severity was highest after an initial dew period of 42–48 h, and severe defoliation followed inoculation at a temperature range of 15–25 °C. The optimum post-inoculation temperature after dew treatment for disease severity was 20–25 °C. In field inoculation tests, high disease incidence and severity indicate that the pathogen has the potential to control the plant effectively in the field. Humidity and temperature were shown to be the main factors influencing disease expression and lesion development of M. polygoni-cuspidati in a field situation. These results provide valuable information for any future use of M. polygoni-cuspidati as a CBC agent for management of Japanese knotweed in the UK.

Some of the most damaging tree pathogens can attack woody stems, causing lesions (cankers) that may be lethal. To identify the genomic determinants of wood colonization leading to canker formation, we sequenced the genomes of the poplar canker pathogen, Mycosphaerella populorum, and the closely related poplar leaf pathogen, M. populicola. A secondary metabolite cluster unique to M. populorum is fully activated following induction by poplar wood and leaves. In addition, genes encoding hemicellulose-degrading enzymes, peptidases, and metabolite transporters were more abundant and were up-regulated in M. populorum growing on poplar wood-chip medium compared with M. populicola. The secondary gene cluster and several of the carbohydrate degradation genes have the signature of horizontal transfer from ascomycete fungi associated with wood decay and from prokaryotes. Acquisition and maintenance of the gene battery necessary for growth in woody tissues and gene dosage resulting in gene expression reconfiguration appear to be responsible for the adaptation of M. populorum to infect, colonize, and cause mortality on poplar woody stems.