MYCOLOGIA IRANICA
Year:2016 | Volume:3 | Issue:2 |Papers Count:7

Endophytic fungi constitute a remar- kable multifarious group of microorganisms live within plants tissues without causing any obvious negative effect. Endophytic fungi have been found in every plant species examined to date. During an investigation on endophytic fungi, 123 fungal isolates were obtained from healthy twigs and leaves of cherry (Prunus avium) and sour cherry (P. cerasus) trees in Iran. The isolates identified based on sequence data of 18S rDNA (SSU) region, as well as morphological and cultural features. As a result, four species namely Coniothyrium olivaceum, Collophora paarla, Sarocladium strictum and Quambalaria cyanescens identified. All these identified species are new reports as endophytic fungi from P. cerasus and P. avium in the world. Among them, Collophora paarla and Quambalaria cyanescens are new taxa for the mycobiota of Iran.

Yeasts are a polyphyletic group of ascomycete and basidiomycete fungi characterized by having a unicellular growth phase and sexual stages that are not enclosed in fruiting bodies. An attempt was made to identify yeast species in uncultivated soils collected from different areas of Kermanshah province, Iran, by analyzing hypervariable D1/D2 domain of the large subunit (LSU) rDNA gene sequence and comparing the sequences with that available in NCBI database. In this study, 25 soil samples were analyzed and eight species including Rhodotorula toruloides (KP324973)*, Trichosporon coremiiforme (KP055040)*, Naganishia uzbekistanensis (KP324959), Candida catenulata (KP324968), C. paracilopsis (KP324965)*, C. boidinii (KP324 962)*, Lecythophora sp. (KP336745)* and Meyerozyma guilliermondii (KPKP324971, KP324978) were identified. Phylogenetic analysis based on D1/D2 regions allowed us to establish the precise taxonomic placement of each species. The Canonical correspondence analysis (CCA) indicated that elevation, EC, pH, and clay were important environmental parameters influencing basidiomycete yeast distribution in uncultivated soils. In this study, the presence of eight species is confirmed that asterisk species are the new records for the mycobiota of Iran.

Stemphylium as a monophyletic genus of filamentous ascomycetes, comprises both of saprophytic and plant pathogenic species with worldwide distribution. In an investigation of fungi associated with the black (sooty) head mold of wheat and barley in different regions of Golestan, Alborz and Qazvin provinces, thirty–two isolates with typical characteristics of the genus Stemphylium were recovered. All isolates were subjected to morphological assessments and DNA sequence analyses (ITS–rDNA and a part of GPDH gene). As a result, four species viz. Stemphylium alfalfae, S. eturmiunum, S. lycii and S. vesicarium were identified. The association of all identified species with the black head mold symptoms of wheat and barley is reported for the first time and S. eturmiunum and S. lycii are new records to the mycobiota of Iran.

Paecilomyces variotii is one of the most important causal agents of dieback disease in pistachio (Pistacia vera) gardens. The disease affects different parts of the tree, such as branch and trunk. Assessment of genetic structure in different populations of this species will lead to more useful management of pistachio dieback disease. In this study, genetic variation within samples of P. variotii isolates from different geo–climatic origins of Kerman province was studied using ITS– RFLP analysis. Universal primer pairs AB28 and TW81 were used for ITS region amplification. Thirteen restriction enzymes were subjected to digest PCR products. Seven out of the 13 restriction enzyme including: EcoR І, Hpyf 3І, Apa І, Hinf І, Mbo І, Msp І, Rsa І showed restriction pattern. Jaccard's similarity coefficient used to determine of genetics similarity and cluster analysis dendrog was designed by using UPGMA algorithm method. Data analysis showed a high similarity at the level of 70% between isolates and all isolates were divided into 9 distinct groups. Analysis of molecular variance (AMOVA) showed a variation of 85% and 15% among of within isolates, respectively. Based on these results we can conclude that ITS–RFLP is useful for wider genetic diversity assessment and epidemiological studies of distantly related isolates. The future studies could be performed to develop new molecular markers to detect this fungus in field.

In order to determine the fumonisin producing isolates of the Fusarium fujikuroi species complex (FFSC), associated with infected spikes, and ear rot of grass plants, we examined 78 samples collected from Kermanshah province, Iran. Based on morphological characters, twenty two isolates assigned to the FFSC and were identified as F. proliferatum (ten isolates), F. verticillioides (seven isolates), and F. subglutinans (five isolates). This was additionally approved using the specific primers of F. verticillioides, F. proliferatum, and F. subglutinans, i.e. VER1/VER2, PRO1/PRO2, and SUB1/SUB2, respectively. PCR–based detection of the fumonisin–producing isolates of FFSC was also achieved using the primers FUM1 F/FUM1 R. Out of twenty two isolates, eleven isolates (50%) determined as fumonisin chemotype.

In this study, ITS–rDNA region was used to identify some anamorphic powdery mildews in Guilan province. According to the results, Erysiphe species on Vicia faba and Sesbania punicea showed 100% similarity to each other, however, without ITS sequence of holotype of E. sesbaniae it is impossible to make conclusion whether Vicia faba powdery mildew fungus actually belongs to E. sesbaniae or E. trifoliorum complex. ITS sequence from isolate of Lagerstroemia indica powdery mildew showed 100% similarity to E. australiana. Podosphaera on Vigna fells into phylogenetic group containing P. xanthii on cucurbitaceous hosts. ITS sequence of chamomile (Matricaria chamomilla) powdery mildew fungus showed 100% similarity to P. xanthii on Xanthium strumarium. Molecular characteristics and morpho– logical examination of conidia and conidia germin– ation clearly showed that Dahlia powdery mildew in Guilan province is conspecific with G. spadiceus. Anamorph morphology and ITS sequence of Podosphaera on Epilobium and Erysiphe on Platanus orientalis showed that these species belong to P. epilobii and Erysiphe platani respectively.

During a study on fungal diversity in petroleum contaminated soils in Khuzestan province, two new hyphomycetes were isolated for the mycobiota of Iran. Based on the combination of morphological data and ITS–rDNA sequence, the isolates were identified as Alternaria obovoidea and Emericellopsis pallida. Morphological descriptions and illustrations are provided for the species. To our knowledge, this is the first report of these two species from petroleum contaminated soils in the world.