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In a survey of barley leaf spot diseases across East Azerbaijan province in Iran, barley plants with brown leaf spot, were collected from barley fields in the Spiran region, the central district of Tabriz County, East Azerbaijan Province, Iran. The disease incidence was 30 percent in sampled areas. Fungal colonies with similar growth pattern were isolated from symptomatic leaves. The isolates were characterized based on a combination of morphological data and sequence data of ITS-rDNA region as P. semeniperda. Pathogenicity assay was fulfilled using the seed infection method under greenhouse conditions. Correspondingly, P. semeniperdastromata were developed on 90% of intact and 95% of scarifies barley seeds and they failed to germinate. Koch’s postulates were fulfilled by re-isolation of the causal agent from inoculated seeds. To the best of our knowledge, P. semeniperdarepresents a new pathogen on barley in Iran. However, geographical distribution, host range and economic impact of this pathogen on major barley producing areas in Iran remain to be studied.

Heterodera filipjevi is one of the widely distributed cyst nematodes of cereals, causing significant yield losses. This species has been reported from many wheat-producing areas in Iran, including East Azarbaijan province. During the surveys on fungal species associated with H. filipjevi cyst nematode in East Azarbaijan province, several fungal isolates were recovered from shells, egg suspensions, and whole cysts. Integration of cultural and morphological characteristics with sequence data of ITS-rDNA differentiated Auxarthron alboluteum, Exophiala equina, Juxtiphoma eupyrena, Oidiodendron cereale, Periconia macrospinosa and Pleotrichocladium opacum from the cysts of H. filipjevi for the first time worldwide. Additionally, A. alboluteum, J. eupyrena, O. cereale and P. opacum represent new records for the mycobiota of Iran. Here we provide descriptions, fully illustrate these species and further discuss their ecology, host range, and geographical distribution. Their antagonistic potential and pathogenicity on this nematode remain to be studied.

Grape maturity is one of the factors that influences the species diversity of yeasts on grapes. While several studies have been carried out on the species diversity of yeasts on mature grape berries in different grapevine producing countries, there is a paucity of data on the biodiversity of yeasts on immature grape berries worldwide, including Iran. This study was conducted to identify the species diversity of epiphytic and endophytic yeasts on immature grape berries in five selected vine growing regions in northwest Iran. 59 grape samples were collected during early stage of grape berry ripening. The percentage of isolation was 35.5% and 117 yeast isolates were recovered as epiphytes; while, no yeast was isolated as endophyte. Identity of yeast isolates by M13 fingerprinting marker and sequence data of D1/D2 region of 28S rDNA revealed a rich diversity of epiphytic yeast species on immature grape berries, with basidiomycetous yeasts being dominant, whereas ascomycetous yeasts were mostly isolated on mature grape berries in our previous studies. Fifteen yeast species were identified among those, Naganishia uzbekistanensis and N. adeliensis were the predominant. Aureobasidium pullulans was also found on immature grape berries with high frequency. Comparing the locality of the sampling areas, the highest biodiversity index was calculated for the Urmia and Lahrud regions. The grape cultivar was an additional factor shaping the biodiversity. This is the first report of Candida peoriensis and Starmerella graminicola as inhabitants of grape berries and C. peoriensis, S. bacillaris and Vishniacozyma foliicola are new for the mycobiota of Iran.

In a survey of fungal species associated with dieback and decline symptoms on elm trees in Tabriz metropolis (East Azerbaijan province, northwestern Iran), phoma-like coelomycetous fungal isolates were recovered from discolored wood tissues of declining elm trees. A phylogeny inferred based on combined LSU and ITS-rDNA sequence data, clustered our isolate in a separate lineage within the genus Neosetophoma in the family Phaeosphaeriaceae. Here we describe and fully illustrate Neosetophoma ulmi as a novel fungal species. Neosetophoma ulmi can be distinguished from the other Neosetophoma species based on its unique phylogenetic placement and morphological features of conidiomata and conidial dimensions.

In this study, the diversity ofCurvulariaspecies from Iran was explored by integration of morphology and molecular data. Seventy-nineCurvulariaisolates were recovered from plant species with leaf spot symptoms. A phylogeny based on sequences of the ITS-rDNA region and the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene clustered our isolates in 16 species clades within the genusCurvularia, viz.,C. americana,C. coatesiae,C. coicis,C. ellisii,C. eragrostidicola,C. geniculata,C. hawaiiensis,C. heteropogonicola,C. inaequalis,C. intermedia,C. mebaldsii,C. nicotiae,C. prasadii,C. spicifera,C. subpapendorfii, andC. tuberculata.Of those,C. coatesiae,C. eragrostidicola,C. geniculata,C. mebaldsii,C. nicotiae,C. prasadiiandC. subpapendorfiirepresent new records for the mycobiota of Iran.New hosts species are reported forC. americana,C. coatesiae,C. eragrostidicola,C. nicotiae,C. prasadiiandC. subpapendorfii.

Members of the genusPhaeoacremoniumare known to inhabit a wide spectrum of substrates and exhibit diverse lifestyles. Little information is available on fungicolous habits among Phaeoacremoniumspecies. During surveys to Arasbaran forests in East Azerbaijan province, Iran, in 2016, several hyphomycete isolates morphologically resembling the genusPhaeoacremoniumwere recovered from the hymenium ofFlammulina velutipess. lato in different localities with no symptoms on the cap. The isolates were identified asPh. fraxinopennsylvanicumbased on a combination of morphological traits and phylogenetic analyses ofβ -tubulingene sequence data. This is the first report on the occurrence ofPh. fraxinopennsylvanicumonF. velutipesworldwide; however, the pathogenic potential ofPh. fraxinopennsylvanicumonF. velutipesremains unclear. The data presented in the study reveal mushroom forming fungi as possible new reservoir hosts forPhaeoacremoniumspp. Hence, extensive sampling from mushroom forming fungi is required to further explore fungicolous habit ofPhaeoacremoniumspecies.

Coelomycetes include a wide range of fungal species with different life modes. Many species are primary pathogens of plants. Amidst the economic significance of this group of fungi, there are very limited studies regarding the associated mycobiota in Iran. The main aim of this study was to characterize the species diversity of coelomycetous fungi in East and West Azerbaijan provinces with the aid of morphological and molecular methods using sequence data of TUB, ITS and LSU regions. Four species namelyNeocamarosporium calvescens,Plenodomus chrysanthemi, Nothophoma quercina, andDiplodina coloradensiswere isolated and identified from different symptomatic and apparently healthy plants. A full description of each species is provided.Neo-camarosporium calvescens,Plenodomus chrysanthemi, andNothophoma quercinarepresent new records for the mycobiota of Iran, and for each species, new hosts are reported.

Although Iran represents one of the presumed centers of domestication of grapevines, there is a huge paucity of knowledge on yeast species diversity on grapevines in Iran. This study was performed to explore the species diversity amongst the epiphytic and endophytic yeast community on grape berries in Iran. Five different regions were selected for sampling. Out of 59 collected samples, 352 yeast isolates were recovered, of those 315 isolates were epiphytes and 37 isolates were endophytes. Species were identified by a combination of M13 fingerprinting and sequencing the D1/D2 region of 26SrDNA. Twenty three different species were identified as epiphytes and 74% of them were Ascomycota. Among these species, seven (all ascomycetous) were also isolated as endophytes.Hanseniaspora uvarumwas the predominant species both in epiphyte and endophyte detection and had the highest biodiversity (H') and evenness index (E). Other species such asPichia terricola,Metschnikowia sinensisandAureobasidium pullulanswere the further most frequently isolated species. This is the first report ofCandida membranifaciensas inhabitants of grape berries.

ABSTRACTSpecies of Septoriaare commonly associated with leaf spot diseases of a broad range of plant hosts worldwide. During our investigation of fungi associated with leaf spot diseases in northern and northwestern Iran, several Septoriaisolates were recovered from symptomatic leaves on different herbaceous and woody plants in the Asteraceae, Betulaceae, and Salicaceae families. These isolates were studied by applying a polyphasic approach including morphological and cultural data and a multigene phylogeny using a combined data set of partial sequences of the 28S nuc rRNA gene (large subunit [28S]), internal transcribed spacer regions and intervening 5.8S nuc rRNA gene (ITS) of the nuc rDNA operon, actin (actA), translation elongation factor 1-α (tef1), calmodulin (cmdA), β-tubulin (tub2), and DNA-directed RNA polymerase II second largest subunit (rpb2). Four novel species are proposed, namely, Septoria eclipticolaon Eclipta prostrata, Septoria firouraghinaon Cirsium arvense, Septoria guilanensison Populus deltoides, and Septoria taleshanaon Alnus subcordata. All species are illustrated, and their morphology and phylogenetic relationships with other Septoriaspecies are discussed.

The identity ofColletotrichumisolates from northwest Iran was determined based on multi-gene phylogenetic analyses and morphological characteristics. Phylogenetic analysis based on a combination of internal transcribed spacer (ITS-rDNA), glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and beta tubulin (TUB) loci clustered our isolates into four species clades, includingC. americae-borealisonTragopogon graminifolius,Convolvulus arvensis,Heracleum persicumandSorghum halepense,C. destructivumonEchium italicum,C. higginsianumonCampanulasp., andC. salicisonPopulus nigra. Among these speciesC. americae-borealis,C. destructivumandC. higginsianumare new on their hosts in Iran and world. We also reportC. higginsianumfor the first time from Iran.

The genus Cercosporaincludes many important plant pathogens that are commonly associated with leaf spot diseases on a wide range of cultivated and wild plant species. Due to the lack of useful morphological features and high levels of intraspecific variation, host plant association has long been a decisive criterion for species delimitation in Cercospora.Because several taxa have broader host ranges, reliance on host data in Cercosporataxonomy has proven problematic. Recent studies have revealed multi-gene DNA sequence data to be highly informative for species identification in Cercospora, especially when used in a concatenated alignment. In spite of this approach, however, several species complexes remained unresolved as no single gene proved informative enough to act as DNA barcoding locus for the genus. Therefore, the aims of the present study were firstly to improve species delimitation in the genus Cercosporaby testing additional genes and primers on a broad set of species, and secondly to find the best DNA barcoding gene(s) for species delimitation. Novel primers were developed for tub2and rpb2to supplement previously published primers for these loci. To this end, 145 Cercosporaisolates from the Iranian mycobiota together with 25 additional reference isolates preserved in the Westerdijk Fungal Biodiversity Institute were subjected to an eight-gene (ITS, tef1, actA, cmdA, his3, tub2, rpb2and gapdh) analysis. Results from this study provided new insights into DNA barcoding in Cercospora, and revealed gapdhto be a promising gene for species delimitation when supplemented with cmdA, tef1and tub2.The robust eight-gene phylogeny revealed several novel clades within the existing Cercosporaspecies complexes, such as C. apii, C. armoraciae, C. beticola, C.cf. flagellarisand Cercosporasp. G. The C. apii s. lat.isolates are distributed over three clades, namely C. apii s. str, C. plantaginisand C. uwebraunianasp. nov. The C. armoraciae s. lat.isolates are distributed over two clades, C. armoraciae s. str.and C. bizzozeriana.The C. beticola s. lat.isolates are distributed over two clades, namely C. beticola s. str.and C. gamsiana, which is newly described.

Colletotrichum nymphaeaeis the principal causal agent of strawberry anthracnose worldwide, including Iran. For disease management, eco-friendly alternatives such as biological control instead of chemical fungicides are highly desirable. The aim of this study was to compare the efficacy of 20 strains of Trichodermaspp. indigenous to Iran against C. nymphaeae, to a commercial strain of Trichoderma atroviride(SC1) isolated elsewhere, under in vitro and in plantaconditions. The tested strains belonged to T. harzianum(ten isolates), T. pleuroticola(five isolates), T. virens(three isolates), T. asperellum(one isolate) and T. afroharzianum(one isolate). In vitro results showed that most isolates used in this study were able to significantly inhibit mycelial growth of the pathogen in dual culture and non-volatile tests. The majority of the tested Trichodermaspp. isolates produced lytic enzymes, including chitinase, β-1,3-glucanase, protease and cellulase. Besides producing hydrogen cyanide, Trichodermaspp. strains were also shown to be positive in terms of siderophore production and the mycoparasitism process. In plantabioassays revealed that the best indigenous strain (T. virensCCTUT4) significantly reduced anthracnose, at the same rate as the commercial strain, although the standard chemical fungicide (Switch®) was superior in terms of disease control. A positive correlation between disease incidence and severity reduction was detected with increasing population density of the antagonists in this study. The findings of this study indicate that isolating Trichoderma-based biocontrol agents from the crop against whose disease are targeted does not necessarily provide advantages in comparison with a strain having good biocontrol properties and originating from a different substrate.

In a taxonomic survey on the genusExserohilum(Pleosporales, Ascomycota) in Iran, leaf samples were collected from plant species with leaf spot symptoms. Monosporic fungal cultures were established using a spore dilution method.Exserohilumisolates were characterized based on a combination of morphological features and sequence data from the ITS+5.8S rDNA region. In this study we report three species ofExserohilumviz.Exserohilum rostratum,E. turcicumandE. monocerasamong whichE. monocerasis newly recorded for the mycobiota of Iran fromEchinochloa colonaandSetaria sp.Exserohilum turcicum is newly reported onSorghum halepense andPaspalum dilatatumin Iran; while, several new hosts are recorded forE. rostratum namelyAloe vera,S. bicolor,S. halepense,Oryza sativaandSaccharum officinarumin Iran.Setaria sp. andP. dilatatumare recorded as new hosts forE. monoceras andE. turcicumworldwide, respectively. We provide full descriptions and illustrations for each of the three species.

During a survey on the biodiversity of the genusPythiumin northwest region of Iran, three isolates belonging to the genusPhytopythium(Peronosporales) were isolated from the rhizosphere ofJuncussp. from the Myaneh region andCirsiumsp. from the Meshkin-Shahr region. Based on combination of cultural, morphological, cardinal growth rate and sequence data from ITS-rDNA, the isolate fromJuncussp. was identified asPp. litoraleand two isolates fromCirsiumsp. were identified asPp. oedochilum. Phylogenetic analyses of the ITS-rDNA sequences clustered our isolates with representative sequences forPp. litoraleandPp. oedochilumisolates from GenBank in thePhytopythiumclade. The generaJuncusandCirsiumare new hosts forPp. litoraleandPp. oedochilum, respectively. Both species represent new records for the mycobiota of Iran. With this paper, we provide full illustration for these two species and further discuss their phylogeny and morphology with closely related species.

The devastating Sigatoka disease complex of banana is primarily caused by three closely related heterothallic fungi belonging to the genus MYCOSPHAERELLA: M. fijiensis, M. musicola, and M. eumusae. Previous phylogenetic work showing common ancestry led us to analyze the mating-type loci of these Mycosphaerella species occurring on banana. We reasoned that this might provide better insight into the evolutionary history of these species. PCR and chromosome-walking approaches were used to clone the mating-type loci of M. musicola and M. eumusae. Sequences were compared to the published mating-type loci of M. fijiensis and other Mycosphaerella spp., and a novel organization of the MAT loci was found. The mating-type loci of the examined Mycosphaerella species are expanded, containing two additional Mycosphaerella-specific genes in a unique genomic organization. The proteins encoded by these novel genes show a higher interspecies than intraspecies homology. Moreover, M. fijiensis, M. musicola, and M. eumusae contain two additional mating-type-like loci, containing parts of both MAT1-1-1 and MAT1-2-1. The data indicate that M. fijiensis, M. musicola, and M. eumusae share an ancestor in which a fusion event occurred between MAT1-1-1 and MAT1-2-1 sequences and in which additional genes became incorporated into the idiomorph. The new genes incorporated have since then evolved independently in the MAT1-1 and MAT1-2 loci. Thus, these data are an example of the evolutionary dynamics of fungal MAT loci in general and show the great flexibility of the MAT loci of Mycosphaerella species in particular.

ABSTRACTThe devastating Sigatoka disease complex of banana is primarily caused by three closely related heterothallic fungi belonging to the genus Mycosphaerella: M. fijiensis, M. musicola, and M. eumusae. Previous phylogenetic work showing common ancestry led us to analyze the mating-type loci of these Mycosphaerellaspecies occurring on banana. We reasoned that this might provide better insight into the evolutionary history of these species. PCR and chromosome-walking approaches were used to clone the mating-type loci of M. musicolaand M. eumusae. Sequences were compared to the published mating-type loci of M. fijiensisand other Mycosphaerellaspp., and a novel organization of the MAT loci was found. The mating-type loci of the examined Mycosphaerellaspecies are expanded, containing two additional Mycosphaerella-specific genes in a unique genomic organization. The proteins encoded by these novel genes show a higher interspecies than intraspecies homology. Moreover, M. fijiensis, M. musicola, and M. eumusaecontain two additional mating-type-like loci, containing parts of both MAT1-1-1and MAT1-2-1. The data indicate that M. fijiensis, M. musicola, and M. eumusaeshare an ancestor in which a fusion event occurred between MAT1-1-1and MAT1-2-1sequences and in which additional genes became incorporated into the idiomorph. The new genes incorporated have since then evolved independently in the MAT1-1 and MAT1-2 loci. Thus, these data are an example of the evolutionary dynamics of fungal MAT loci in general and show the great flexibility of the MAT loci of Mycosphaerellaspecies in particular.