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Colletotrichum nymphaeae is the primary causal agent of strawberry anthracnose in Iran resulting in epidemics in strawberry fields in recent years. Due to the hemibiotrophic nature of the pathogen, early detection in symptomless, infected plants, especially in nurseries could be advantageous for disease management. Assessing inter-species variation by rep-PCR fingerprinting of Colletotrichum spp. within the C. acutatum species complex causing strawberry anthracnose revealed a specific genomic segment amplified with only C. nymphaeae. The amplicon was extracted, purified and novel primer sets were developed based on conventional PCR and loop-mediated isothermal amplification (LAMP) techniques. The genus and species-specific PCR primers were able to discriminate the genus Colletotrichum and C. nymphaeae from other fungal species in pure culture and in assays of diseased, detached leaves. Similar results were observed for LAMP, but it was more sensitive compared to the PCR assay. Using both assays, asymptomatic strawberry plants infected with C. nymphaeae strain CCTUCch32 were readily detected. These results show that the primer sets developed in this study based on conventional PCR and LAMP techniques can be effective for early detection of C. nymphaeae, which can contribute to improved control strategies for strawberry anthracnose.

Pyrenophora graminea is the main fungal species associated with barley leaf stripe disease worldwide. Even though a heterothallic mating strategy has been proven for P. graminea, this species is mainly known based on the asexual morph in nature and there is no available information on the prevalence of an active sexual cycle within the populations of this species in Iran as well as many other barley-producing countries. The feasibility of a cryptic sexual cycle within Iranian isolates of P. graminea was assessed through analyzing the distribution and frequency of the mating type alleles on micro-spatial and macro-geographical scales. A total number of 306 P. graminea isolates were obtained from 93 fields in 45 geographical regions across East Azerbaijan province during 2016–2017. A multiplex PCR assay was developed for simultaneous identification of P. graminea and screening of its mating type alleles using previously designed primer sets. Using the multiplex PCR assay, a 435-bp band was consistently amplified from all P. graminea isolates; while a 1300-bp fragment or a 1150-bp fragment was only amplified from the isolates harboring MAT-1 and MAT-2 alleles, respectively. The mating type identity of 164 isolates was determined as MAT-1 and 142 isolates as MAT-2. Results of the present study revealed a nearly equal distribution (1:1 ratio; X2=1.582) of mating type alleles within and between different populations of P. graminea. Results of the micro-spatial and macro-geographical distribution of mating types showed that both mating types were often present on almost all studied scales, including: within the same lesion of each leaf from a single barley plant, from the same field or different fields in the same region, and from different regions. Based on the results of the current study and referring to the earlier reports on the population structure of P. graminea, it is concluded that this pathogen undergoes regular cycles of sexual recombination in most of the examined regions.

Between March and September 2012, grapevines in vineyards of Meshginshahr county located in Ardabil province as well as Azarshahr, Ajab Shir, and Malekan counties located in East Azerbaijan province, north-western Iran represented general decline symptoms and in some cases black vascular discoloration. Annular or irregular discoloration, dark vascular streaking, and V-shaped unilateral canker or brown necrosis were observed in the pit and vascular tissues of the infected stems. These symptoms were accompanied with necrotic and wilted leaves. Nine fungal isolates having analogous morphological traits were recovered from symptomatic tissues on potato dextrose agar culture medium. Morphological and molecular characterizations confirmed the identity of all nine isolates as Kalmusia variispora (formerly known as Dendrothyrium variisporum). Random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) analyses were conducted for genetic diversity assessment of 13 K. variispora isolates from grapevine, one isolate from Rosa hybrida and one isolate from Pinus eldarica and the results indicated the existence of polymorphism among the isolates (77.27% and 81.25% for RAPD and ISSR, respectively). The clustering of RAPD and ISSR analyses revealed that there was no correlation between the isolates and their geographical as well as host origins. A pathogenicity assay confirmed K. variispora to be pathogenic on grapevine plants (cv. Keshmeshi) causing similar symptoms as those observed in naturally infected grapevines. Kalmusia variispora is associated with grapevine decline symptoms and grapevine trunk disease in Iran.

Two new α-pyrone derivatives, udagawanones A (1) and B (2), along with the known compounds (Z)-4-hydroxy-3-(3-hydroxy-3-methylbut-1-en-1-yl)benzoic acid (3), isosclerone (4), cyclo-(L-Leu-L-Pro) (5), and cyclo-(L-Pro-L-Tyr) (6), were isolated from cultures of the endophyte Neurospora udagawae. Their structures were elucidated by extensive spectroscopic methods and single crystal X-ray diffraction. Both compounds feature oxidized functionalities at the C-2 position not previously observed in other tetrasubstituted α-pyrones from fungi. Compound 1 exhibited moderate antibacterial (vs. Staphylococcus aureus) and antifungal (vs. Rhodoturula glutinis) activities and cytotoxicity against KB3.1 cells.

Two new metabolites possessing the unusual 1-oxa-7-azaspiro[4.4]non-2- ene-4,6-dione core (2, 3) along with the recently described pseurotin A3 (1) were isolated from the pathogenic fungus Wilsonomyces carpophilus (previously named Stigmina carpophila). The producer organism was obtained from Prunus armeniaca collected in Iran and was identified by morphological and molecular phylogenetic methods. The structures of the isolated compounds were elucidated on the basis of extensive NMR spectroscopic analysis, high-resolution mass spectrometry and ECD analysis. The compounds were screened for their antimicrobial, cytotoxic, nematicidal and biofilm inhibition activities but, no significant effect was observed. To the best of our knowledge, this is the first report on the isolation of secondary metabolites produced by W. carpophilus.

Trunk diseases are potential threats to the poplar industry worldwide, including Iran. A survey on trunk diseases of Populus nigra in north-western Iran revealed a new canker disease associated with dieback and decline of this host in West Azarbaijan Province of Iran. Wood samples were collected from poplar trees showing canker, dieback and decline symptoms and taken to the laboratory. A total of 173 fungal isolates were recovered from symptomatic tissues, of those 147 isolates had similar cultural and morphological features on potato dextrose agar. Based on a combination of morphological characteristics and phylogenetic inferences including DNA sequence data from the internal transcribed spacer regions (ITS1, 5.8S rDNA, and ITS2), all 147 isolates were identified as Cryptosphaeria pullmanensis. The remaining 26 isolates were identified as Cytospora chrysosperma. Pathogenicity of Cr. pullmanensis on two-year-old P. nigra and Populus alba saplings under glasshouse conditions confirmed that Cr. pullmanensis is pathogenic on P. nigra and P. alba. Cryptosphaeria pullmanensis is here reported from Iran causing Cryptosphaeria canker on poplar trees for the first time. However, its host range, the extent of geographical distribution and management strategies remain to be examined.

During October–November of 2017 and 2018, powdery fungal masses were observed on leaves of Persian speedwell (Veronica persica) on the campus of Tabriz University, East Azerbaijan Province, Iran. Infected leaves were collected and subjected to a taxonomic study. Based on morphological characteristics the fungus was identified as Golovinomyces orontii species complex. A phylogeny inferred based on ITS-rDNA sequence data clustered our isolate as Golovinomyces bolayi. Golovinomyces bolayi has recently been segregated from the Golovinomyces orontii species complex. Golovinomyces bolayi can be differentiated from other closely related species based on morphological characteristics of conidiophores and ITS-rDNA phylogeny. This is the first report of this species from Iran on Persian speedwell.

Polygonatum odoratum (Mill.) Druce (Angular Solomon's seal) is a well-known ornamental plant and herbal drug, which is used in traditional medicine. Severe leaf spots were observed in wild Angular Solomon's seal plants in a public park in Trento, Italy. A combination of morphological and molecular characteristics, including sequence data of ITS-rDNA, large subunit (LSU), beta tubulin (TUB) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) led to identification of two species, namely Phoma odoratissimi and Colletotrichum dematium s. str., isolated from these leaf spots. Pathogenicity of the isolates was confirmed on wounded leaves of Po. odoratum; indeed, both species induced leaf spot symptoms on inoculated leaves within 10 days of inoculation. This is the first report of leaf spot disease caused by Ph. odoratissimi and C. dematium s. str. on Po. odoratum, which can be considered a new host for both the species examined in this study. In addition, isolation of Ph. odoratissimi represents a new record for the mycobiota of Italy.

Strawberry anthracnose, caused by Colletotrichum nymphaeae, is mainly controlled by the application of synthetic chemical fungicides. The present study assessed the antimicrobial activity of essential oils (EOs) from dill (Anethum graveolens L.) seed against C. nymphaeae. The antifungal effects of dill seed EO on C. nymphaeae was initially evaluated in vitro and further extended as in vivo condition. The results indicate that in the contact and volatile assays, dill seed EO significantly inhibited mycelial growth of C. nymphaeae at all concentrations tested. Conidia germination was also significantly inhibited at concentrations of 250 – 1000 ppm. Disease incidence and severity of anthracnose on strawberry fruits were significantly reduced compared with infected control, from concentrations of 500 and 50 ppm, respectively. The results confirm the efficacy of dill seed EO against C. nymphaeae, which may represent an alternative to synthetic chemical fungicides to control strawberry anthracnose pre- ...

Anthracnose caused by Colletotrichum spp. is one of main strawberry diseases worldwide. The disease recently arrived in Iran and become epidemic in the Kurdistan province. A combination of morphological, molecular and pathogen-host interaction approaches (referred to the consolidated species concept) were applied to isolates from symptomatic strawberry tissues collected in Iran. Multi-gene phylogenetic analysis based on ITS-rDNA, beta-tubulin (TUB2) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) identified the species as the S5 clade of Colletotrichum nymphaeae. No significant intraspecies variation was observed in terms of morphology and pathogenicity. No significant genetic variation was observed among the isolates using inter simple sequence repeat analysis (ISSR) and primer pair combination of ERIC1/BOX and ERIC2/BOX fingerprinting markers. Based on the results of this study, it can be postulated that the C. nymphaeae population in Iran established itself from a single origin due to a founder effect. More generally, molecular dating based on relaxed clocks indicates co-radiation of C. nymphaeae S5 and strawberry plants and suggests high reciprocal specificity between the host and pathogen.

Rhynchosporium commune(formerly known asRhynchosporium secalis), the causal agent of scald disease on barley, is known to spread asexually by splash dispersed conidia. However, there are multiple lines of evidence for the possibility of a clandestine sexual cycle occurrence in this species including extensive genotypic diversity, equal distribution of mating type alleles across the world and expression of mating type genes. In the current study, the potential for the occurrence of a sexual cycle amongst the Iranian population ofR. communewas assessed by analyzing distribution and frequency of the mating type alleles at both micro and macro-spatial scales. A total of 95 single-conidialR. communeisolates were obtained from different barley fields in Kurdistan province. Previously designed primers were applied in a multiplex PCR assay to study distribution and frequency of the mating type alleles within and between populations. Totally, 67 isolates were determined asMAT1-1and the remaining 28 isolates asMAT1-2throughout the sampling counties. The results obtained at a macro-spatial scale revealed that unlike Kamyaran county (bothMAT1-1andMAT1-2at an equal ratio), an unequal distribution of mating type genes was dominant amongR. communeisolates in both Mariwan and Dehgolan counties. Our findings support a predominantly asexual reproduction for Mariwan and Dehgolan counties and the possibility of sexual stage occurrence in Kamyarna county.

Trunk diseases are potential threats for almond productivity and longevity worldwide, including Iran. In a recent survey on fungal species associated with trunk diseases of almonds in north-western Iran, Collophora isolates (tentatively identified as Collophora hispanica) were recovered with high frequency from wood samples with internal necrosis and brown to black vascular streaking of almond trees showing symptoms of decline. However, the pathogenic potential of Collophora isolates on almond trees in Iran remains unproven. In this study, the identity of the isolates was further confirmed as C. hispanica based on a combination of morphological data and sequence data of ITS-rDNA region, and pathogenicity of C. hispanica isolates on almond was evaluated using excised shoot method and in greenhouse experiments. Collophora hispanica isolates induced lesions statistically different from the control, in both excised shoot method and greenhouse assays. Significant differences were observed among the isolates in the length of the lesion induced on wood. Collophora hispanica should be considered as the main trunk pathogens of almond trees in north-western region of Iran. The distribution and host range of this new pathogen on almond remains to be studied.

Togninia minima is the main fungal species associated with grapevine leaf stripe disease worldwide. This species is mainly known from its asexual state in nature; nevertheless, a biallelic heterothallic mating strategy has been confirmed for this species based on in vitro crossing studies. There are no data available on the incidence of an active sexual cycle within the populations of this species in many grapevine-producing countries as well as Iran. The possibility of a clandestine sexual cycle within the Iranian isolates of T. minima was evaluated by analysing the distribution and frequency of the mating-type alleles on a microspatial and a macrogeographical scales. Towards this aim, a total of 90 T. minima isolates were recovered from grapevines with esca disease from the vineyards in north and north-western Iran. A multiplex PCR method previously designed by authors was applied for simultaneous identification and determination of the mating-type alleles in T. minima populations. The results on the screening of mating-type alleles using multiplex PCR method revealed the mating-type identity of 77 isolates as Mat1-2 and 23 isolates as Mat1-1. Our results showed that both Mat1-1 and Mat1-2 isolates are present in a single vineyard and even on single vines. The distribution of mating-type alleles in the sampled area skewed from the 1 : 1 ratio (77 : 23); however, co-occurrence of both mating types in a single vineyard and even on single vines is suggestive for the presence of an active sexual cycle for T. minima in north-western Iran.

In the present study, the antagonistic capability of bacterial agents inhabiting the rhizosphere of sugarbeet plants were evaluated against Cercospora beticola Sacc. under laboratory and greenhouse conditions. After preliminary screening using the dual culture method, 14 strains with higher antagonistic capability were selected for further inhibitory assays against C. beticola. Bacterial strains were identified based on the sequence data of the small subunit-rDNA (SSU-rDNA) gene. Based on the SSU sequence data, the identity of bacterial strains were determined as Bacillus (10 strains: RB1, RB2, RB3, RB4, RB5, RB6, RB7, RB8, RB9, RB10), Paenibacillus (two strains: RP1, RP2), Enterobacter (one strain: RE), and Pseudomonas (one strain: RPs). The results obtained in this study showed that in all of the assays (dual culture, volatile and non-volatile metabolites) bacterial antagonists significantly inhibited the growth of C. beticola compared to the control. Bacillus (RB2) showed the highest inhibition rate on C. beticola in all of the assays. Based on the results of the laboratory assays, three bacterial strains RB2 (Bacillus), RPs (Pseudomonas), and RE (Paenibacillus) were selected for greenhouse assays. The experiment was designed based on a completely randomised design (CRD) with the application of antagonists prior to, simultaneously, and after inoculation with C. beticola on sugarbeet leaves. The reduction in disease severity was evaluated seven days after inoculation. The results of greenhouse assays were consistent with the results of laboratory studies. The obtained results showed that bacterial antagonists significantly reduced the disease severity when compared to the control.

In November 2017, white, powdery colonies were found on leaves, stem and petals of Zinnia (Zinnia elegans) in Firouragh, the Khoy region (West Azerbaijan province), Iran. Whitish colonies, present mainly on the upper surface of the leaves, were effuse or forming patches, thin, white, and evanescent to persistent. The fungus associated with the white colonies was identified as Golovinomyces sp., based on morphological characteristics of its asexual state including conidial shape, dimension and germination pattern. Chasmothecia were not observed. The PCR amplification and sequencing of the ITS-rDNA did not differentiate our isolates from G. ambrosiae, G. spadiceus and G. circumfusus. This study provides the first report on the occurrence of Golovinomyces sp. on Z. elegans in Iran.

We report the first case of chafer beetle [Anisoplia austriaca(Herbst 1783)] mortality caused byActinomucor elegansvar.elegansin wheat fields of the Kurdistan province, Iran. For three years, dead larvae ofAnisoplia austriacawere collected from wheat fields of the Kurdistan province. Similar isolates of a fast-growing fungus were recovered from all samples. The fungal isolates were identified asA. elegansvar.elegansbased on morphological and cultural characteristics. The identity of the species was further confirmed using sequence data of the ITS (Internal Transcribed Spacer) region of ribosomal DNA. Koch’s postulates were fulfilled by the inoculation of the larvae ofA. austriacaandGalleria mellonella(Linnaeus, 1758) (as the model insect) using the spore suspension ofA. elegansvar.elegans. The viability of sporangiospores was evaluated using a spore dilution technique on germination medium. The results on the pathogenicity (100% mortality inA. austriacalarvae) and viability tests (germination: 95.45%) demonstrated thatA. elegansvar.eleganscan be considered as a potential biocontrol agent against the chafer beetle. Field experiments are still required to evaluate the capacity ofA. elegansas a biological control agent.

The genus Colletotrichum comprises a number of plant pathogens of major importance which cause anthracnose diseases on a wide range of woody and herbaceous plants worldwide. With the advent of molecular studies, it has been shown that most of the previously known species e.g. C. boninense, C. acutatum, and C. gloeosporioides have been split into several species. In the present study, the identity of Colletotrichum isolates from the northern and northwestern zone of Iran were determined based on multi-gene phylogenetic analyses. Phylogenetic analysis based on a combination of internal transcribed spacer (ITS), beta tubulin (TUB), histone H3 (HIS), calmodulin (CAL), and actin (ACT) loci, clustered our isolates into three clades, including C. salicis on Salix sp., Colletotrichum sp. (C. fuscum sensu lato) within the C. destructivum species complex on Viola sp., and C. fructicola on Citrus sinensis, Malus domestica, Gleditsia caspica, and Sambucus ebulus. These three species are new for mycobiota of Iran. According to these results, Viola sp. from West Azerbaijan (Khoy-Firouragh) is a new host for Colletotrichum sp. in the C. destructivum species complex. Furthermore, C. sinensis from Mazandaran (Behshahr), and G. caspica, and S. ebulus from Guilan (Talesh), are new host records for C. fructicola.

Trunk diseases are potential threats for the grapevine industry owing to the worldwide incidence and economic impact of the diseases. Several fungal groups are known to be involved in these diseases. In a survey on grapevine trunk diseases in northern Iran, Cytospora isolates were repeatedly recovered from vines showing decline symptoms. The symptoms appeared as pale brown to brown streaks in longitudinal cuts of shoots. The morphological and cultural characteristics of the isolates were in agreement with the description of Cytospora chrysosperma. Sequence data of the ITS-rDNA region was used to further confirm the identity of the species. Phylogenetic analysis based on the sequence data obtained in this study and the sequences from GenBank, confirmed the morphological identification. Our isolates were clustered together with C. chrysosperma isolates known from other woody host plant species. The pathogenicity assay on detached shoots of grapevines induced the same symptoms as was observed in field conditions. Although, C. chrysosperma is known from several woody hosts in Iran, the occurrence of this species on grapevines showing decline symptoms is new. The economic impact, distribution, and degree of involvement of C. chrysosperma in decline of vines in other regions of Iran remains to be studied.

The genus Pythium, with slightly over 140 described species, has been classified traditionally with other filamentous, coenocytic, sporangia-producing fungi as “Phycomycetes”. However, with recent advances in chemical, ultrastructural and molecular studies, Pythium spp. are now considered as “fungus-like organisms” or “pseudo-fungi” and are placed in the kingdom Chromista or kingdom Stramenopila, distinct from the true fungi or the kingdom Fungi. There is no comprehensive web-based identification key available for the identification of all described Pythium species. This article describes a web-based identification tool (which has been described by the authors under the name of Fungid) that uses morphological features. For the isolate in question, the software compares the unknown isolate with near to 90 known species submitted in the database. One or more than one species is suggested to the user by the software.

Bacillus thuringiensis var. kurstaki (Berliner) (Bt) has been suggested as a biological control agent for Tuta absoluta (Meyrick). The objective of this study was to determine the interaction between abamectin, azadirachtin, indoxacarb, chlorantraniliprole, dichlorvos and metaflumizone with Bt. Effect of recommended doses of the chemical insecticides on colonisation of Bt was also investigated in culture medium. Except for metaflumizone, none of the chemicals tested reduced the colonisation of Bt compared with control. Interaction between Bt and the chemical insecticides on 2nd-instar larvae was also assessed. In interaction tests, Bt was applied at LC50 level, 0, 12, 24 or 36 h after treating the larvae with LC10 or LC25 of the chemical insecticides. An antagonistic effect was observed in all treatments where Bt was applied immediately after the chemical insecticide. Also, antagonism was observed when treatment with Bt was done 12 h after azadirachtin and metaflumizone applications. Applying Bt 12 and 24...

During 2014–2016, symptoms and signs of a powdery mildew disease were observed on the leaves and twigs of sour cherry (Prunus cerasus) in orchards from Firouragh in the Khoy region (West Azarbaijan province) of Iran. Young leaves and twigs were covered with a powdery growth consisting of mycelium and the asexual reproductive structures of a powdery mildew species. Affected leaves were curled upward and smaller than uninfected leaves, while affected twigs were stunted and often defoliated. The fungus was identified as belonging in the genus Podosphaera, based on morphological characteristics of its asexual state. Chasmothecia were not observed. The PCR amplification and sequencing of its ITS-rDNA revealed that the causal agent was Podosphaera clandestina. This is the first record on the occurrence of P. clandestina on sour cherry in Iran.

In November 2015, white, powdery colonies were found on leaves of greengage (Prunus domestica subsp. italica var. claudiana) in the Meshginshahr (Ardabil province) and Khoy (West Azarbaijan province) regions of Iran. The circular colonies with chasmothecia scattered throughout were present mainly on the upper surface of the leaves. The fungus associated with the white colonies was identified as Podosphaera tridactyla using morphological and molecular characteristics. This paper details the first record of a powdery mildew on greengage in Iran.

Colletotrichum nymphaeae is 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 Trichoderma spp. indigenous to Iran against C. nymphaeae, to a commercial strain of Trichoderma atroviride (SC1) isolated elsewhere, under in vitro and in planta conditions. 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 Trichoderma spp. isolates produced lytic enzymes, including chitinase, β-1,3-glucanase, protease and cellulase. Besides producing hydrogen cyanide, Trichoderma spp. strains were also shown to be positive in terms of siderophore production and the mycoparasitism process. In planta bioassays revealed that the best indigenous strain (T. virens CCTUT4) 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.

Cornus mas (Cornelian cherry or European cornel) is a deciduous shrub with edible fruits that have medicinal benefits and is native to southern Europe and south-western Asia. This shrub grows wild in Arasbaran forests and the Qazvin region in Iran. In this study a new fruit rot disease was discovered on cornelian cherries in Arasbaran forests located in the north-west zone of Iran. Fruit samples were collected from severely infected C. mas trees in October 2017. Ten fungal isolates with the same morphological characteristics were recovered from symptomatic tissues on potato dextrose agar culture medium. The causal agent of the disease was identified as Pilidium lythri based on macro and micro morphological and molecular characterizations. In addition, random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) fingerprintings were used to assess five P. lythri isolates (one isolate from each five parts of the forest) from cornelian cherry, five isolates from strawberry, and two isolates from olive. Based on the results, no polymorphism was observed among the isolates, denoting limited genetic variability. Pathogenicity assays confirmed P. lythri isolates to be pathogenic on cornelian cherry and strawberry fruits in vitro condition, irrespective of their origin. Based on the data presented in the current study, P. lythri isolates from different hosts showed a homogeneous genetic structure with no host preference. This is the first occurrence of P. lythri causing fruit rot on cornelian cherry in Iran and the world.

During surveys on grapevines trunk diseases in vineyards at different localities in East and West Azerbaijan and Ardabil provinces, Iran, wood samples (two, three year-old cordons) were collected from grapevine showing decline symptoms, including leaf yellowing and necrosis, stunted growth, internal wood necrosis, black vascular discolouration. Nine fungal isolates with similar morphology were recovered from grapevines with decline symptoms in five different areas, which one-third of the isolates were recovered as the sole fungal agents. The identity of fungal isolates was determined as Quambalaria cyanescens based on the combination of cultural and morphological characteristics and DNA phylogeny. Pathogenicity trials based on excised shoot assay and potted grapevine under greenhouse conditions confirmed Q. cyanescens being pathogenic on grapevines; the isolates induced symptoms similar to those observed in naturally infected grapevines. Our findings confirm Q. cyanescens as a new fungal trunk pathogen of grapevine. Members of the genus Quambalaria are known to cause leaf spot, shoot blight and canker disease on Eucalyptus and its relative Corymbia. The current study is the first regarding pathogenicity of the Q. cyanescens on woody hosts; in previous studies Q. cyanescens has proven to be non-pathogenic to Corymbia spp. The host range, extent of geographical distribution and economic significance of this new pathogen on grapevine remains to be studied.

Several species of the genus Alternaria are involved in leaf spot disease of sunflower, with Alternaria alternata being the dominant species responsible for this disease in Iran and many other sunflower-producing areas, worldwide. The disease causes a progressive destruction of the photosynthetic apparatus, resulting in annual yield loss. The routine disease management strategies are not effective for disease control; hence, alternative measures for disease management are of great interest. In the present study, the efficacy of Trichoderma harzianum T22 and Trichoderma sp. on biological control of the causal agent was evaluated under laboratory conditions. The effect of Trichoderma isolates on dry weight (DW) and radial growth (RG) rate of A. alternata was evaluated using dual culture, volatile and non-volatile cellular metabolites. The results obtained in this study revealed that in both Trichoderma isolates, non-volatile cellular metabolites had the highest inhibitory effect on DW and RG rate of the cau...

A new fruit rot disease was observed on olive fruits (Olea europaea L.) in the orchards of the Tarom region (Zanjan province, Northwest Iran). The symptoms of the disease appeared as water-soaked lesions on fruits, later becoming brownish and coalescing, which resulted in rotten and mummified fruits. Isolation was made from symptomatic tissues. The causal agent of the disease was identified as Pilidium concavum based on morphological and cultural characteristics. The identity of the species was further confirmed using sequence data from ITS-rDNA region. The ITS sequence generated in this study showed 100 % homology with the sequence data for P. concavum from GenBank. Koch’s postulates were fulfilled by inoculation of surface-sterilized fresh olive fruits under laboratory conditions using a spore suspension. This is the first report of the occurrence and pathogenicity of P. concavum on olive fruits anywhere in the world.

Phaeoacremonium spp. are known as the main Hyphomycetes associated with esca disease symptoms on grapevines worldwide. The role of other woody hosts in proximity of vineyards as a possible inoculum source for the causal agents of grapevine esca disease mainly remains unknown. The aim of this study was to investigate the occurrence of Phaeoacremonium spp. on pome and stone fruit with trunk diseases symptoms in northwestern parts of Iran. For this purpose, wood trees samples were collected from apple and apricot trees with trunk disease symptoms. Isolation was made using routine plant pathology methods. Based on the morphological and cultural characteristics, Phaeoacremonium aleophilum and Phaeoacremonium iranianum were identified from apple trees and P. aleophilum was recovered from apricot trees with trunk disease symptoms. A phylogenetic analysis based on the sequence data from β-tubulin gene further confirmed the identity of the species as P. aleophilum and P. iranianum. The results of inoculation assay...

Olive oil is the most important product of olive fruits with worldwide consumption, particularly in Mediterranean countries. Olive oil is generally extracted mechanically from the olive fruits. Some biotic and abiotic factors may affect the quality of oil extracted from olive fruit. Contamination with fungi during growth period in the garden or during the conservation of the harvested crop under storage condition may leave negative effects on the quality of olive oil. However, there is no data available on the effects of fungal infections on qualitative properties of olive oil in Iran. In the present study effects of several fungal groups previously isolated from rotten olive fruit in olive orchards including Alternaria alternata, Fusarium nygamai, Aspergillus ochraceus, Arthrinium phaeospermum, Cladosporium cladosporioides, Aureobasidium pullulans, Epicoccum nigrum, Penicillium expansum, Truncatella angustata, Trichothecium roseum and Trichoderma harzianum were evaluated on some qualitative properties of...

In recent years, grapevine trunk diseases have gained growing attentions due to worldwide incidence of the disease. In a survey on fungal agents associated with grapevine trunk diseases in northern Iran, wood samples were collected from grapevines having the symptoms of declination. Isolation was made using routine plant pathology methods. A coelomycetous fungus with appendage-bearing conidia was recovered from symptomatic tissues. Based on morphological and cultural characteristics, the causal agent of the disease was identified as Truncatella angustata. The identity of the species was further confirmed by sequence data of internal transcribed spacer-rDNA region. A phylogeny inferred using sequence data obtained in this study, together with the sequences from GenBank, clustered our isolates together with T. angustata known from other host plant species. Pathogenicity tests performed on detached shoots of grapevines led to the same symptoms as observed in field conditions. This is first study on the pathogenicity of T. angustata on grapevine in Iran and first report on the occurrence of T. angustata on grapevine in Iran.

Cornus mas L. (Cornaceae), known as European Corneal, is native to south Europe and south-west Asia. This deciduous shrub with edible and medicinal fruits grows wild in Arasbaran forests located in...

Esca is a very important and destructive disease of grapevine in many grapevine producing countries. Several groups of fungi have been reported from grapevines with esca disease symptoms; however, Phaeoacremonium species are the main hyphomycete fungi involved in this disease. In recent years, esca disease symptoms with consequent decline disease have frequently been observed in vineyards of north-western Iran. Nevertheless, the involvement of Phaeoacremonium spp. with esca disease symptoms in this region remains unknown. During 2008–2010 growing seasons, wood samples were collected from vines showing typical esca disease symptoms such as interveinal leaf chlorosis with subsequent necrosis and various types of internal wood deterioration in north-western parts of Iran. A total of 44 Phaeoacremonium-like hyphomycetes were recovered from sampled materials. Fungal isolates were subjected to tentative morphological identification and were further characterised by using sequenced data from ITS-rDNA and β-tubli...

The genus Pythium, with slightly over 280 described species has been classified traditionally with other filamentous, coenocytic, sporangia-producing fungi as “Phycomycetes”. However, with recent advances in chemical, ultrastructural and molecular studies Pythium spp. are now considered as “fungus-like organisms” or “pseudo-fungi” and are placed in the kingdom Chromista or kingdom Straminopila, distinct from the true fungi or the kingdom Fungi. Little is known about the biodiversity of Pythium in Iran. This paper attempts to assess the position of the genus Pythium and provides details of the historical development of the study of Pythium in Iran. The survey list contains 33 species, 4 species groups and 1 unknown species of Pythium.

Race-specific resistance of barley (Hordeum vulgare L.) to the yellow rust caused by Puccinia striiformis f. sp. hordei, has been reported to be short-lived. Slow rusting resistance has been reported to last for a long time. Twenty Iranian barley cultivars along with resistant and susceptible controls were tested during the 2009-2010 and the 2010-2011 cropping seasons, in field plots at the Ardabil Agricultural Research Station (Iran). The cultivars were tested to identify slow rusting genotypes through epidemiological variables which included: final rust severity (FRS), apparent infection rate (r), relative area under the disease progress curve (rAUDPC), and coefficient of infection (CI). Moreover, differential sets were evaluated in order to determine effective and ineffective resistance genes to barley yellow rust. Results of the mean comparison of resistance parameters showed that cultivars Makouee, Dasht, Fasih, and Arass had low values of FRS, CI, r and rAUDPC compared with susceptible cultivars. The cultivars Walfajre, Abidar and Sahand which had moderate values of the different parameters, were marked as possessing a moderate level of slow rusting. The rest of the cultivars which had high values of different quantitative parameters, were grouped as having a low level of slow rusting or as susceptible. The correlation coefficient between different parameters of slow rusting was significantly high (r = 0.83-0.98). The virulence profile of the prevalent races revealed that rpsEm1, rpsEm2, rpsHF, Rps4, rpsVa1, rpsVa2, rpsAst were effective, and rps2, Rps1.b were ineffective resistance genes during the two year testing period.

Trunk diseases are a potential threat for the almond industry in Northern Iran. In a survey on fungal agents associated with almond die back and decline in East Azerbaijan province, located in Northwest of Iran, acremonium-like hyphomycete isolates with hyaline and simple conidiophores and hyaline cylindrical phialides with a finely pigmented apical region and deep, flaring collarettes were repeatedly recovered from symptomatic tissues. Fungal isolates were identified as Calosphaeria pulchella based on cultural and morphological characteristics. The identity of the species was further confirmed based on the sequence data from LSU and ITS rDNA regions. A phylogeny inferred using ITS sequence data, clustered the Calosphaeria isolates together with Calosphaeria pulchella isolates in GenBank known from Prunus persica and Prunus avium. The results of pathogenicity assay using an excised shoot method showed that Calosphaeria pulchella is highly pathogenic on almond. The distribution and host range of this new p...

Essential oils have been widely used against a range of plant pathogens due to their antimicrobial effects. Mycorrhization of aromatic plants can enhance the concentration of essential oil components obtained from these plants. This study evaluated the effect of essential oils obtained from dill ( Anethum graveolens ), inoculated with Funneliformis mosseae, against Colletotrichum nymphaeae , the causal agent of strawberry anthracnose. Dill plants were inoculated with F. mosseae under field conditions, essential oils were extracted from the seeds of inoculated and non-inoculated dill and chemical analysis of their composition was carried out. The efficacy of non-inoculated and inoculated essential oil against C. nymphaeae was evaluated through in vitro experiments. Gas chromatography-mass spectrometry analysis showed that constituents were the same in essential oils extracted from seeds of inoculated and non-inoculated dill plants, however several components increased significantly with inoculated as compared with non-inoculated treatments particularly known antimicrobial compounds including limonene and carvone. Essential oil from inoculated plants inhibited mycelium growth (contact and volatile phases) and conidia germination of C. nymphaeae more efficiently than oil from non-inoculated plants. Essential oil from both inoculated and non-inoculated dill plants affected the morphology in a similar manner and deterioration in the morphology was more evident when higher concentrations (500 and 1000 mg/L) were applied. The increase in antimicrobial efficacy due to F. mosseae may have a positive impact on the further development of dill essential oils for plant protection against diseases. This is the first evidence of a positive effect of F. mosseae colonization of dill on the antimicrobial activity of its essential oil against C. nymphaeae .

Since 2008, there have been several reports on the occurrence of decline symptoms on grapevines in vineyards of East and West Azerbaijan provinces in Northern Iran by local farmers as well as plant protection clinics. The disease symptoms appeared as stunted growth, shoot dieback and wedge-shaped wood necrosis in cross section through the wood. Isolations were made from the surface sterilized tissues using routine plant pathology techniques. Based on the sequence data of ITS-rDNA and morphological characteristics of the conidia, the isolates were identified as Botryosphaeria dothidea. Pathogenicity assay using an excised shoot method revealed the isolates being pathogenic on grapevine. This is the first report on the occurrence of Botryosphaeria dothidea on grapevine in Iran.

Sunflower leaf spot is one of the most common as well as important foliar diseases of this host in northern Iran. Stemphylium vesicarium was revealed to be one of the causal agents of sunflower leaf spot based on morphological and molecular characteristics. The identity of the species was confirmed using sequence data from the ITS rDNA region and glyceraldehyde-3-phosphate dehydrogenase (gpd) gene sequences. Pathogenicity of the fungus was proven by inoculation of four-week-old sunflower plants (cv. Euroflor) under controlled conditions. This is the first report on the incidence of S. vesicarium on H. annuus anywhere in the world.

Yellow rust caused by Puccinia striiformis f. sp. hordei is an important disease of barley (Hordeum vulgare L.) in some parts of the world. We compared the effectiveness of different types of resistance in field plots at Ardabil Agricultural Research Station (Iran) during 2010–2011. Yield components along with slow rusting parameters including final rust severity (FRS), apparent infection rate (r), relative area under disease progress curve (rAUDPC) and coefficient of infection (CI) were evaluated for 25 barley cultivars. In all, two barley cultivars with race-specific resistance, 19 cultivars with different levels of slow rusting resistance and four susceptible cultivars were included in two experiments with and without fungicide protection under high disease pressure. Barley cultivars with slow rusting resistance displayed a range of severity responses indicating phenotypic diversity. Mean thousand kernels weight (TKW) losses for susceptible, race-specific and slow rusting genotypes were 31, 3 and 12%, ...

Yellow rust caused by Puccinia striiformis f. sp. tritici is undoubtedly, the most important fungal disease of wheat especially in central and Western Asia that causes significant annual yield losses. Production and use of cultivars with durable resistance is the best controlling method. For this purpose, study on reaction of 19 promising lines to yellow rust was carried out in Ardabil in 2008-2009 cropping year. Assessment of adult plant reaction was conducted under field condition with artificial inoculation. Seedling test was also conducted in greenhouse. Slow rusting resistance at adult plant stage was assessed through the Infection Type (IT), Disease Severity (DS), Relative Area Under Disease Progress Curve (rAUDPC) and Coefficient of Infection (CI). Results of mean comparison of CI and rAUDPC indicated that the lines; C-87-1, C-87-2, C-87-3 and C-87-18 had the highest CI and rAUDPC. The lines C-87-6, C-87-8 and C-87-11 had the susceptible reaction at seedling test and were moderately resistant to moderately susceptible at adult plant stage. Consequently, these lines with low rAUDPC (15.2 to 27.8%) most probably could have slow rusting resistance. The lines C-87-4, C-87-5, C-87-13, C-87-14 and C-87-17 had not any infection or were at low level of infection, thus, they were selected as immune or resistant lines. The rest lines were moderately resistant to moderately susceptible. In this study, correlation analysis of different parameters also showed highly strong relationship of CI with rAUDPC and disease severity (R2 = 0.91 and 0.98, respectively).

The Sigatoka disease complex of banana involves three related ascomycetous fungi, Mycosphaerella fijiensis, M. musicola, and M. eumusae. The exact distribution of these three species and their disease epidemiology remain unclear, because their symptoms and life cycles are rather similar. Disease diagnosis in the Mycosphaerella complex of banana is based on the presence of host symptoms and fungal fruiting structures, which hamper preventive management strategies. In the present study, we have developed rapid and robust species-specific molecular-based diagnostic tools for detection and quantification of M. fijiensis, M. musicola, and M. eumusae. Conventional species-specific polymerase chain reaction (PCR) primers were developed based on the actin gene that detected DNA at as little as 100, 1, and 10 pg/μl from M. fijiensis, M. musicola, and M. eumusae, respectively. Furthermore, TaqMan real-time quantitative PCR assays were developed based on the β-tubulin gene and detected quantities of DNA as low as 1 pg/μl for each Mycosphaerella sp. from pure cultures and DNA at 1.6 pg/μl per milligram of dry leaf tissue for M. fijiensis that was validated using naturally infected banana leaves.