Mycologia Iranica
Volume:11 Issue: 2, Summer and Autumn 2024

Rhizoctonia solani is a destructive pathogen on several plant species. The isolates of R. solani AG- 2-2 IIIB are important due to their diverse host range and association with bean diseases such as web blight, hypocotyl rot, and damping off. In response to the adverse environmental effects of chemical fungicides, the possibility of resistance in pathogen populations, and unpredictable prices of chemicals, adopting alternative strategies such as the use of biological fungicides is necessary for managing the diseases caused by R. solani. Members of the genus Acrophialophora, such as A. jodhpurensis, are valuable sources of metabolites with diverse applications in agriculture, biotechnology, industry, and medicine. This study investigated the effects of different culture conditions on the biocontrol of R. solani AG-2-2 IIIB by A. jodhpurensis. The addition of fructose (1%), ammonium chloride (3.5%), and asparagine (0.1%) as the most effective carbon, nitrogen, and amino acid sources, respectively, significantly increased the growth rate and release of volatile and non-volatile metabolites, as well as the antagonistic activity of A. jodhpurensis against the pathogen. Microscopic observations showed structural changes in R. solani hyphae affected by A. jodhpurensis. Seed coating was performed with A. jodhpurensis spores containing 1% alginate, molasses, or Arabic gum as stickers. Among the stickers, alginate had the greatest effect in reducing the disease index and increasing growth factors in beans. Therefore, seed coating with the endophytic fungus A. jodhpurensis is effective in protecting beans against R. solani.

Nano-calcite, or calcium carbonate nanoparticles, is valued for its stability and versatile applications, particularly in agriculture, where it enhances soil quality, regulates pH, improves nutrient delivery, and promotes sustainable crop yields. In this research, nano-calcite was synthesized using Acremonium egyptiacum IRAN 5247C, isolated from grapevine necrotic wood, under sedimentary conditions through fungal urease production. Key factors including urea and calcium concentrations, pH, incubation time, and temperature were optimized using a one-factor-at-a-time (OFAT) approach, resulting in a maximum yield of 595 mg of calcite per 10 ml of solution. Field emission scanning electron microscopy (FE-SEM) imaging revealed that the nanocrystals were predominantly spherical, averaging 73.5 ± 8.02 nm in size, with a distribution range of 25 to 125 nm. X-ray diffraction (XRD) and Fourier transform infrared-Raman (FTIR-Raman) spectroscopy confirmed a well-defined crystalline calcite structure characterized by carbonate ions. This study reports the first synthesis of nano-calcite using Acremonium egyptiacum, with precise control over particle shape and size, an ideal feature for applications in concrete reinforcement, bio-cementation, and agriculture.

During a study on the biodiversity of fungal taxa associated with symptomatic plants in the forests and gardens of Guilan and Khorasan Razavi provinces (northern and northeastern Iran) two diseased plant samples were collected: one from large-leaved linden (Tilia platyphyllos Scop.) in Guilan, showing branch canker symptoms, and the other from a fig tree (Ficus carica L.) in Khorasan Razavi, exhibiting necrotic leaf spot symptoms. Two fungal isolates were recovered, identified, and characterized through a combination of morphological characteristics and phylogenetic analysis of the ITS rDNA genomic regions. These isolates were identified as Ophioceras leptosporum on large-leaved linden and Schizothecium inaequale on the fig tree. According to the literature, O. leptosporum and S. inaequale are new ascomycetous taxa for the fungal flora of Iran. Furthermore, large-leaved linden and fig tree are reported here for the first time as new hosts (matrix nova) for O. leptosporum and S. inaequale, respectively, worldwide.

Calotropis procera is a shrub or small tree growing in tropical regions of the southern provinces in Iran. The economic benefits of the shrub include the use of latex and extract in traditional medicine. In a survey conducted in the southern provinces of Iran, leaf lesion symptoms were observed on C. procera shrubs. The purpose of the current study was to identify and characterize putative pathogens causing these symptoms. Isolations from the symptomatic tissues yielded predominantly a fungus belonging to the Didymellaceae family of Ascomycota. The causal agent was identified as Neodidymelliopsis cynanchi, based on morphological characteristics, and multilocus phylogenetic analysis using ITS, LSU, rpb2, and tub2 sequences. Pathogenicity tests on four-month-old seedlings of C. procera revealed that the isolates caused typical leaf lesions on the host. To the best of our knowledge, this is the first report of N. cynanchi causing disease on C. procera worldwide and the first report of the occurrence of this species in Iran.

Neosetophoma iranianum has so far only been described in its coelomycetous asexual morph. In this study, the sexual morph for this species was recovered for the first time, from dead branches of Lonicera caprifolium, in North Khorasan Province, Iran. The connection between the asexual and sexual morphs of the species was confirmed by phylogenetic analysis based on ITS rDNA sequence data, and morphological traits. The sexual and asexual morphs of N. iranianum are described and illustrated here, and compared with closely related species. A dichotomous key for the identification of all species assigned to the genus Neosetophoma is also provided.

Contamination of foodstuffs by mycotoxigenic fungi is a major threat to human health. During a study on mycotoxigenic fungi associated with raisins, dried fruits apricot, apple, and white mulberry, and a traditional food (Terkhêna), 50 Penicillium isolates were collected from Mahabad, west of Iran. These isolates showed various ISSR fingerprinting patterns generated by (GTG)5 primer and grouped in 11 distinct clusters. A representative isolate from each cluster was selected for phylogeny and morphological studies. Phylogenetic analyses of BenA sequence data, resulted in the identification of five Penicillium species belong to two different sections Chrysogena (P. chrysogenum and P. dipodomyus) and Fasciculata (P. crustosum, P. palitans and P. polonicum). As far as we know, except P. chrysogenum and P. polonicum which have previously been reported from raisins, all other recognized species here are reported for the first time from all examined foodstuffs around the world. Moreover, P. dipodomyus is reported here as a new record for the mycobiota of Iran.

Species of the Alternaria section Nimbya are plant pathogens or saprophytes associated mainly with the plants in the Cyperaceae and Juncaceae families. Until now, five species from this section have been reported in Iran, but their sexual morphs have not been identified. In the present study, the sexual morph of Alternaria scirpivora was induced under laboratory conditions on PCA medium containing autoclave sterilized culms of Scirpus acutus incubated at 23–25 ºC for 90 days. Mature ascomata were formed after 2–3 months, containing asci and ascospores. The morphological characteristics of the sexual and asexual morphs are described and the phylogenetic relationships of A. scirpivora with closely related species are discussed. This is the first report of the sexual stage of this species in Iran and Asia.

This paper presents an updated revision on Iran's species, host ranges, and geographical distribution of powdery mildew fungi. According to our findings, 154 powdery mildew fungal species belonging to nine genera—viz., Arthrocladiella (one species), Blumeria (two species), Erysiphe sect. Erysiphe (25 species), E. section Microsphaera (21 species), E. section Uncinula (11 species), Golovinomyces (20 species), Leveillula (31 species), Neoerysiphe (three species), Phyllactinia (18 species), Podosphaera sect. Podosphaera (five species), P. section Sphaerotheca (14 species), and Sawadaea (three species)—occur in Iran. Moreover, several records on 88 miscellaneous host plants belong to unidentified anamorphic states considered as Oidium s.l. spp., which are kept in a separate section. In this updated version, 673 host plant species are reported, representing 339 genera.

Fermented foods and beverages play an important role in maintaining human health. Yeasts are one of the essential microbial groups for food fermentation and are found in fermented products. The current study aimed to investigate the diversity of yeast species from fermented foods and beverages in some regions of Iran. Samples were collected from traditional fermentation products including sourdough, kombucha, kefir, and water kefir. Initially, 38 yeast isolates were studied morphologically and biochemically, followed by M13 DNA fingerprinting. Representatives identified through DNA fingerprinting were selected for rDNA-LSU (D1/D3 regions) sequencing. As a result, six species were identified. The identified yeast species belonged to ascomycetous yeasts, namely Saccharomyces cerevisiae, Pichia membranifaciens, P. kudriavzevii, P. fermentans, Kazachstania servazzii, and Kluyveromyces marxianus. Sourdough samples showed more diversity of isolated yeast species compared to kombucha, water kefir and kefir samples.  Saccharomyces cerevisiae was the only yeast species isolated from kombucha, kefir, and water kefir samples. The current research findings provide valuable insights into the yeast diversity of traditional fermented products.

Rice is the most important food for a significant portion of the world's population, especially in Asia. The infection of rice plants with Fusarium species is a major global problem. For the morphological and phylogenetic identification of Fusarium species associated with rice, a widespread sampling was conducted from the root, crown, leaf sheath, and stem of the rice plants in various rice-cultivating areas across Fars, Golestan, Guilan, Isfahan, Khuzestan and Mazandaran provinces. Species-specific primers were used to identify three closely related species: F. fujikuroi, F. proliferatum, and F. verticillioides, which could not be distinguished based on morphological criteria alone. By combining morphological characteristics and sequence data of TEF1-α and β-tubulin genomic regions, nine species including F. fujikuroi, F. verticillioides, F. proliferatum, F. globosum, F. andiyazi, F. anthophilum, F. incarnatum, F. culmorum and F. oxysporum were identified among 242 isolates examined. This study reports the first occurrence of Fusarium andiyazi on rice in Iran. In addition to the known causal agents of bakanae disease, the pathogenicity test revealed that two additional species F. culmorum and F. anthophilum can also be considered agents of bakanae disease on rice.

The tea plant (Camellia sinensis) is an economically important shrub cultivated in Northern Iran. Various fungal genera, including Phyllosticta spp., are associated with leaf spots on tea plants. Several species of Phyllosticta exhibit similar morphological and, in some cases, molecular characteristics. Therefore, precise species identification requires integrating all available data, including morphological features, molecular sequences, host-fungus relationships, pathogenicity tests, etc.  To clarify the taxonomic position of Phyllosticta species associated with tea plants in Iran, a multi-faceted approach was employed, incorporating morphology, field observation, ITS, tef-1α, and ACT sequences, along with clustering analysis. This comprehensive study revealed that the previously identified P. theacearum shares characteristics with P. capitalensis, which is primarily recognized for its endophytic nature. This marks the first report of P. capitalensis being associated with tea plants in Iran.

Specimens of tooth fungi were collected from pine tree cones (Pinus sp.) in the Northern forests of Iran and transported to the laboratory for identification. The macroscopic characteristics of the samples were examined visually and microscopically using an Olympus BH2 microscope (Olympus, Japan).The macroscopic features of the specimens were as follows: Fruit body hydnate-stipitate, pileus semicircular or kidney shape, broadly convex or flat, 1-3 cm across, covered with fine brown hairs. Hairs flexible when young, becoming tough and turning dark brown with age, growing singly or gregariously.The underside of the pileus is covered with a crowded array of tiny tooth or needle-shaped spore-bearing structures or hymenium, up to 3 mm long, 0.5 mm diameter, initially whitish to cream, turning brown with age.Stipe eccentric or lateral (attached to one edge of the pileus), 1.5 to 2 mm in diameter and up to 5 cm in length, tough, and covered with short fine hairs of the same color as the pileus.Basidiospores broadly ellipsoid or globose, 4.5–5.5 × 4–5 µm, hyaline, smooth, or becoming finely spiny when mature, turning blue in Melzer’s reagent (amyloid). Spore print white.The basidia four-spored with basal clamp connection, 15–24 × 3–4 μm. The hyphal system dimitic, comprising both generative and skeletal hyphae.Specimens were identified as Auriscalpium vulgare Gray (Russulales, Auriscalpiaceae,) based on Koski-Kotiranta & Niemelä (1987) and Larsson & Larsson (2003). This is the first report of a species from the genus Auriscalpium Gray in Iran.