Rostaniha
Year:2017 | Volume:18 | Issue:1|Papers Count:10

In order to investigate the Oomyceteous species of the rice paddy fields of Fars province (Iran), during 2013–15, infected roots and crowns together with soil around seedlings and irrigation water were sampled. Based on the morphological, morphometric and physiological studies along with phylogenetic analyses of internal transcribed spacer sequences based on neighbor joining method, twoPhytophthora species from Clades 6 and 8, including P. inundata, andP. pseudocryptogea and three Phytopythium species from a distinct clade, including Phpy. litorale, Phpy. ostracodes, and Phpy. sterile were identified. Phytopythium litorale, and Phpy. sterile were distinguished through morphological studies along with phylogenetic analysis.Phytopythium sterile was also new to the Oomyceteous mycobiota of Iran. All species were reported for the first time in the world from rice rhizosphere.

Gypsophilawith approximately 150 species represents the fourth largest genus of Caryophyllaceae and the second genus of tribeCaryophylleae. Iran is the second main center of Gypsophila diversity with 38 species in the world. ConsideringGypsophila as one of the most polymorphic genus of the family and almost half of its taxa distributed in Iran as endemic, thus makes it as a significant genus from taxonomic and nomenclatural points of view.Moreover, following the IUCN Red List criteria, about half of these endemic taxa are categorized as Critically Endangered (CR D.); hence, the protection of these taxa and their limited habitats is necessary. Pollen grains of 40 taxa (Table 1) were studied by electron microscopy for the first time in Iran (Figs 2–5). However, these attributions do not support sections which are made based on morphological characters and rather can be used to separate some close taxa.The pollen grains of Gypsophila are monade, apolar, pantoporate with 12 pores, rounded polyhedral, tectate with granulate microechinate-microperforate ornamentation. Pores are annulate, operculate. Pollen grains size (20.7–32 mm), operculum diameter (1.6–6 mm), distance between pores (2.3–7 mm) and operculum thickness are variable among taxa (Table 2).Gypsophila pilosa var. pilosa, and G. platyphylla have the largest while G. antoninae has the smallest pollen grains. The smallest pores and, therefore, the minimum diameter of the operculums can be seen in G. acantholimoides.The largest and thickest operculum is owned by G. virgata. A phenogram of Iranian Gypsophila taxa derived from palynological analysis using UPGMA method is also given herewith (Fig.1).

Thirty-seven isolates ofFusarium graminearum species complex obtained from wheat heads with Fusarium head blight symptoms were selected and used for phylogenetic studies. They were collected from different localities of Moghan plain (Ardebil province, Iran). Partial sequences of translation elongation factor 1-alpha (TEF), putative reductase (RED) and UTP-ammonia ligase (URA) genes were amplified using specific primers and sequences were analyzed using Maximum Parsimony method. Almost all strains of F. graminearum species complex belonged to F. graminearum sensu stricto. The results indicated homogeneity within F. graminearum species complex. Inter-simple sequence repeat markers (ISSR) were employed to study the genetic structure of F. graminearum s.s. populations collected from five localities in Moghan plain. The ISSR markers were generated by five primers and data analysed using UPGMA method with Jaccard's coefficient. Cluster analysis showed that all isolates were divided into four clades with 82% similarity level. The analysis of molecular variation indicated that most of the gene diversity (97%) was distributed within populations, whereas 3% of the variation was found among populations. Phylogenetic species identification and genetic diversity knowledge of major agent of FHB disease will be useful in defining the risk of pathogen evolution as well as benefiting disease management strategies.

Onosma L. as a rich taxa in Boraginaceae including about 150–180 species, centered mainly in Irano-Turanian region. The genus faced with several systematic complexities lead to many identification problems as well as morphological polymorphism. Several authors have used setae characteristics inOnosma as the most important diagnostic evidence in delimitation and classification of species in addition to the natural group. Besides palynological and karyological studies, molecular evidences have also confirmed recent classifications. This genus has been classified as a sister toMaharanga A.DC as a central Asiatic taxon of Boraginaceae. Several ambiguities in identification and differentiation of species created a wide range of complexities among and also between the species.Onosma elwendicum Wettst., O. bulbotricum DC., O. rostellatum Lehm., and O. dichroanthum Boiss. are some examples facing with these problems. Also, Onosma olivieri H. Riedl., and O. lanceolatum Boiss. & Hausskn. as closest taxa in Flora Iranica, eventually are geographical ecotypes and can be synonym taxa. Besides this, some taxa following O. sharifii H. Riedl., O. paboti H. Riedl., and O. caeurelescens Boiss. do not have detectable type specimens with no specimens obtained from type localities. Therefore, every comment on taxonomy as well as systematic study of the genus, need to a perfect assessment of diverse ecotypes and geographical populations together with a detailed field works with emphasis on ecology and phytogeography of their habits.

The genus Phoma Sacc. consists of important fungal plant pathogenic species occurring on economically important cultivated crops in spite of many other saprobic species. Thus, the aim of this study was to identify 35 isolates of Phoma species and related taxa collected from different hosts by means of morphological and molecular characters.Multi-locus phylogenetic analyses based on ITS1-5.8S-ITS2, actin and β-tubulin gene regions were conducted.Therefore, seven species including Boeremia exigua, Didymella acetosellae, D. bellidis, D. pinodella, Neocamarosporium betae, Phoma destructiva var. destructive, and P. medicaginis were identified and described, and among them, three species includingD. bellidis, D. acetosellae, and P. destructiva var. destructiva are new records for the mycobiota of Iran. Also, B. exigua, and D. pinodella are reported for the first time from new host plants including Paliurus spina-christi, and Trigonella-foenum graecum, respectively. The morphological features and phylogenetic analyses were able to clarify the generic and species delimitation very clearly.

Endophytic fungi are beneficial fungi to their host plants and help them to endure biotic and abiotic stresses with different methods. In order to identify some endophytic fungi of sour cherry trees, healthy plant samples including twigs and leaves were collected from several provinces of Iran. A total number of 176 isolates were obtained and studied taxonomically. Based on morphological features and ITS regions sequence data, 10 different fungal species, namely, Aureobasidium namibiae, A. pullulans, Alternaria multiformis, A. rosae, Botryosphaeria dothidea, Cladosporium tenuissimum, Coniolariella limonispora, Didymosphaeria variabile, Epicoccum nigrum, Lecanicillium muscarium, and Neoscytalidium dimidiatum were identified as endophytic fungi of sour cherry trees in Iran. Among these species, Aureobasidium namibiae is new for the mycobiota of Iran. All identified species except A. pullulans, are reported here for the first time as endophytic fungi of sour cherry trees in the world.

During 2015–16, the presence of micromycetes species in aquatic ecosystems was studied in Iran. Samples were collected from rivers, lakes and wetlands. For isolation, agar disks were transferred to plates containing water samples.The plates were incubated at 25–27oC for 21 days in 12 h light/12 h dark condition. Then from the mycelium grown on the agar disks, pure cultures were obtained. Finally, an isolate was identified asAquanectria penicillioides (Ingold) L.Lombard & Crous, based on morphological and molecular data (sequences of ITS rDNA). Based on available literatures, this species is reported as new taxon for mycobiota of Iran and is described below: Colony on PDA reached 50 mm in diam., after 14 days at 25oC in continuous dark condition. The hyphae are colorless (Fig.1a). Chlamydospores were formed in moniliform chain, brown in color and 15–28 (20) × 10–16 (14) mm in diameter (Fig.1b). The colony on PDA forms few or no conidiophores but, if a small mycelial disc is cut off and submerged in water, numerous submerged conidiophores will be produced within two days. The submerged conidiophores are hyaline and penicillium-like (Fig.1c, d); apical phialides are 15–21 (18) mm long, 2–2.5 mm wide.Conidia (phialospores) are 31–48 (39.5) mm long, 2–2.5 (2.3) mm wide and each conidium is curved or sigmoid. The hyaline conidia may be aseptate or divided by a single septum into two, more or less equal cells (Fig.1e, f).Specimen examined: Iran: Lorestan province, Kaka Reza river, 18.10.2015, Razieh Poursaeid (IRAN 2794C).Morphological features of this isolate were similar to that of A. penicillioides described by Ingold (1944).Lombardet al. (2015) showed that, the aquatic genus Aquanectriawas established to accommodate two fungal species previously treated as members of the genera Flagellosporaand Heliscus (Ingold 1942, Ranzoni 1956). In the present study, the sequence of Aquanectria (accession number: MF085359) showed 99% homology with valid sequences of previously identified and deposited data in the GenBank. Phylogenetic trees constructed based on ITS regions sequences showed that, the Iranian specimen is placed in the same clade with A. penicillioidesreported from other authors (Fig.2).

In recent years, tulip flowers have been grown extensively in parks and green spaces of Urmia city (NW Iran). During the surveys in a period from 2014–16, characteristic symptoms of the blue mold rot were observed on both planted and stored tulip bulbs, as the bulbs were covered with a white to bluishgreen mycelia and spores. In order to determine the fungi associated with tulip bulbs (Tulipa gesneriana L.), the bulbs with characteristic rot symptoms or signs (Fig.1a-c) were collected from different green spaces and municipal greenhouses. The fungi were isolated in two ways: First, small pieces of fungal colonies were taken with a sterile fine needle and a suspension of spores was prepared in sterile distilled water. …

During the investigation of fungi associated with black (sooty) head mold of wheat and barley in different regions of Golestan, Alborz and Qazvin provinces (Iran) in growing seasons of 2014–15, several isolates with typical characteristics of the genusHarzia Costantin were collected. Based on the morphological characteristics, all isolates were identified as H. acremonioides (Harz) Costantin. To the best of our knowledge, this is the first report of the species to the mycobiota of Iran and is described below: Colonies on malt extract agar (MEA) fast growing, reaching 7 cm diam. after seven days at 23–25° C under continuous darkness, at first colorless, later pale brown to cinnamon brown, effuse, cottony. Sporulation abundant, mostly from surface and to a lesser extent from aerial mycelia (Figs 1A, B). Hyphae hyaline, septate and branched, 5–7 mm in wide. Conidiophores hyaline, sympodially branched, straight or slightly curved, 1–2 septate, tapered to a fine tip point, up to 70 mm long, 5–7mm wide near the base and tapering to 1–2 mm tip (Figs 1C, D). Blastoconidia are produced at the tip of the conidiophores and their branches, solitary, dry, one celled, globose to obovoid, almost smooth walled, colorless at first, later becoming light brown to cinnamon brown, 19–28 × 16–24 mm (Figs 1E, F). A phialidic anamorph attributed to this species in some literature, was not observed in this study.To confirm the morphological identification, isolate HA-1 was selected for DNA analysis. The nuclear ITS-rDNA was amplified and sequenced using ITS4/ITS5 primer pairs (Whiteet al.1990). The resulting sequences were deposited in Gen Bank under accession number KX064398. Blast search of obtained sequencesin GenBank showed a high nucleotide similarity (99%) with that ofH. acremonioides strain NRRL 54327 (HQ698593).The genusHarzia contains four accepted species, namely, H. acremonioides, H. cameroonensis, H. velata, and H. verrucosa which are often distinguished from each other by conidium characteristics (Domschet al.2007, Crouset al.2013). Harzia acremonioides is the most common species of the genus and has been reported from all climatic regions of the world. It has frequently been isolated from seeds of different plant species and from a lot of other different substrates (Blaszkowski & Piech 2002, Domschet al.2007, Seifert et al.2011).However, in Iran, H. verrucosa has been reported from barley grains in Golestan province (Ahmadi & Sadravi 2008).Harzia acremonioides can be easily distinguished from H. verrucosa by its verrucose, globose to subglobose and smaller (16–23 mm diam.) conidia.Specimens examined: Iran: Golestan province, Gonbade-Kavous, barley head, May 2015, A. Poursafar, isolate HA-1 (IRAN 2839C); Kordkuy, wheat head, May 2015, A. Poursafar, isolate KQ8-10.