Introduction: Black dot disease triggered by Dilophospora alopecuri causes considerable damage in some fields in Golestan province, North of Iran. D. alopecuri is its causal agent and carried in to wheat by wheat gall nematode. Extracellular appendages on the conidia adhere to the cuticule of the nematode juveniles. The disease was reported in united state of America, Canada, Germany, Ugoslavia, India and Pakistan. The fungi is classDothideomycetes and order Dothideales. The geographical distribution of disease was studied in South-Eastern Australia in the summer 1995. The disease in Iran has been reported by Bamdadian since 1973 from Baluchistan, Isfahan, Golestan, Khorasan, Kerman and Khuzestan. The disease agent causes considerable damage in some fields in Golestan province, North of Iran. Symptoms have been found during a survey of foliar disease of wheat in Golestan province. The disease incidence was very low but fungus interaction with seed gall nematode causes considerable damage. The symptoms start with yellow spindle-shaped flecks which develop and become tan brown with black border. This spots may occur on peduncle and heads. The pathogen survives as mycelium in host debris or as conidia on seeds. The purpose of this study was determining the geographical distribution, disease incidence (DI) and disease severity (DS). Then molecular identification of isolates with ITS rDNA in North of Iran, Golestan province. Material and Methods: Wheat fields infected with the disease in the cities of Golestan province were visited and subjected to sampling during spring 2017-2018. 42 samples suspected to infection with the twist disease were gathered from seven cities of Golestan province. The rate of disease distribution from seven cities farms with disease symptoms, three farms were selected in each crop year and their geographical coordinates were recorded. In this research mapping the geographical distribution of disease was prepared by ArcGIS10. 2 software. During 2018 and 2019, a survey was conducted to characterize the disease incidence (DI) and disease severity (DS). The D. alpoecuri leaf spot reading scales rate carried out in this study. No visible symptoms are observed and the leaf remain a health 0,A few chlorotic lesions are present and the infection site is a tan-spot colored 1: Necrosis and chlorosis both exist on the leaf 2: A few pycnidia are visible on the infected site and less than 30% of the leaf is occupied by pycnidia 3: The entire leaf is covered by pycnidial lesions scored 4. A significant difference was observed between the disease rates in the two cropping years. Seven D. alopecuri isolates were identified on the based on morphological and molecular parameters. After purification of fungal isolates, 50 conidia and pycnidia were selected in each isolate and the length and width of pycnidia, conidia cell number, conidia size (length and width), colony shape on the culture medium were also measured in the laboratory. After that identifying of the fungus isolates pathogenicity test was performed in the greenhouse. The D. alopecuri spore suspension with 1. 75× 106 CFU concentration and for nematode population with 25000 larvae (L2) were used for inoculation to plants. After three months symptoms of leaf spot (twist) disease was appeared in tillering stage. Fungal DNA extraction from mycelium mass of selected isolates was performed by Murray and Thompson (1980) method and part of ITS region was amplified using ITS4 and ITS5 primers by polymerase chain reaction (PCR). The amplified PCR products of fragments were purified and sequenced at sequencing Microsense Company in Switzerland. Results and Discussion: Comparing of harvested fungal isolates which have been grown on PDA medium showed some variation in different characteristics such as the number of conidia walls, conidia appendages and pycnidia size. In both subsequent years, maximum disease incidence (DI) and disease severity (DS) was measured in Kalaleh by 3. 6% to 3. 9%, while for Bandar-Torkaman, the city with the lowest DS, were1. 3% to 1. 65%. The average size of conidia length was 4-8×1 μ, m in diameters. The pathogenicity test showed that the D. alopecuri is capable to produce twist disease symptoms only in the presence with seed gall nematode in the host. The nucleic acid sequences of Internal Spacer Transcribed (ITS) regions for Golestan isolates showed 100% similarity and had small genetic similarity with D. alopecuri MH859142. 1 deposited in NCBI Genbank. The sequences belong to D. alopecuri from Gonbad, Aqala, Azadshahr, Maravehtapeh, Kalaleh, Minodasht cities were registered in NCBI Genbank with MW302360, MW291507, MW291561, MW303438, MW303517, MW303518 accession number, respectively. Conclusion: This is the first study carried out on the morphological and molecular characteristics of twist disease agent isolates, disease severity and its distribution in Golestan province as a major wheat production area of Iran. Many of results especially molecular data and submitted sequences form Iranian isolates of D. alopecuri to databanks are new for Iran.

Background: Saprolegniasis is an important aquatic fungal disease that causes severe damages at different growth stages of aquatic animals.Saprolegnia parasitica has been identified as an important pathogen in aquaculture. This study was investigated the activity of antifungal methanolic extracts of Foeniculum vulgare, Achillea millefolium, Satureja hortens is, Cinnamomum zeylanicum, as well asArtemisia annua essential oil against S. parasitica in comparison with formalin.Materials and Methods: In this descriptive study, Saprolegnia parasitica originated from rainbow trout’s farm effluent. Phenotypic identification was performed and amplification of ITS rDNA region was adjusted by using of two general primers like ITS1 and ITS4, subsequently sequencing by use of internal primer were performed. The antifungal effects of the plants were investigated based on broth microdilution method and compared by formalin.Results: The results of sequencing verified the obtained fungus is S. parasitica. In broth microdilution method, the essential herb Artemisia inhibited the growth of S. parasitica at a concentration of 128 mg/ml (MIC=128 mg/ml). At the same concentration, however, it did not show any fungicidal activity (MFC ³ 2048 mg/ml). Methanolic extracts of the plants fennel, yarrow, Savory, and cinnamon displayed no direct effects on S. parasitica Conclusion: Based on the results obtained in the present study, Artemisia can be classified as a powerful antifungal essential plant. The essence of Artemisia performed more effectively compared to formalin for the growth inhibition of S. parasitica.

Potato and onion are the most important commercial crops in Iran especially Isfahan province. Anthracnose caused by several species of Colletotrichum spp. In order to identify and determine the possibility of cross contamination among pathogenic species of each host to another host, sampling was carried out from potato and onion fields in Faraydan, Daran, Damaneh, Chadegan and Ashgerd regions from Isfahan province. Morphological characteristics led to 170 isolates of Colletotrichum that 120 isolates belonged to C. coccodes from potato and 50 isolates belonged to C. circinans from onion. 35 isolates of those 170 isolates were selected to amiliphy DNA using specific primers for the ITSrDNA region and sequencing. Pathogenicity test was conducted in greenhouse conditions. The results indicated the pathogenicity of C. circinans on onion After 30 days, but no symptoms were found on potato inoculated by thes isolates, while pathogenicity of C. coccodes was confirmed on potato after 60 days and no any symptoms was found on onion plants. The results might have used to control anthracnose in potato and onion fields.

The study was intended to investigate the morphological, morphometric and molecular characterization of eight geographical isolates of the entomopathogenic nematode Steinernema feltiae from northwest of Iran.The results showed no detectable morphological variations, but significant morphometric variations were recorded among the isolates. Clustering based on morphometry of infective juveniles, classified the isolates in the following three separate groups: group I consists of IRA30 and IRA25; group II includes IRA21, IRA23, IRA34, IRA28 and IRA21 and group III contains of IRA17. Clustering the isolates based on the male' s morphometric characters, yielded nearly similar results and four groups were constructed as follows: group I is made up of IRA22, IRA23 and IRA21; group II holds IRA25, IRA34 and IRA28; group III contains IRA30 and IRA17 constitutes group IV. No intraspecific variation was observed among PCR-RFLP patterns of the Steinernema native isolates resulted from16 restriction enzymes but significant variations were recorded within the isolate Pumping by HinfI, MspI and MboI. Although these markers serve as effective tools in separating the native isolates from the exotic ones, they are unable to detect variations among native isolates. Therefore, only ITSrDNA sequence based phylogenetic analysis can effectively clarify the intraspecific variations of S. feltiae.

Wheat as the most strategic agricultural crop has an important role in food security, and so the most cultivation area among the agronomic crops, belongs to wheat. Fungi associated with root and crown of wheat, are effective on crop production and yield. Therefore, in order to identify mycobiota of wheat root and crown in Zanjan province, sampling was carried out from 58 rainfed and irrigated wheat fields during cultivation season of 2011. Out of 286 fungal isolates obtained, 248 isolates belonged to hyphomycetes as identified morphologically. Sequence data of ITSrDNA region was used to confirm the identify of the isolates. Accoreding 10 genera and 23 species of Alternaria alternata, A. atrum, A. chlamydospora A. tenuissima, Aspergillus auricomus, A. niger, Bipolaris sorokiniana, Botrytis cinerea., Curvularia australiensis, C. inaequalis, Fusarium acuminatum, F. avenaceum, F. chlamydosporum, F. equiseti, F. redolens, F. sambucium, F. scirpi, F. solani, F. tricinctum, Microdochium nivale, Periconia circinata, Penicillium chrysogenum, Trichoderma atroviride were identified. Pathogenicity test of some fungal isolates were conducted based on completely randomized design with three replications under greenhouse condition. According to the results B. cinerea, B. sorokiniana, F. avenaceum, F. acuminatum, P. circinata, C. australiensis, F. equiseti, F. solani and A. chlamydospora caused disease with different severity on their host. Among the species, B. cinerea, B. sorokiniana, F. avenaceum and F. acuminatum caused visible root necrosis. A. auricomus was isolated for the first time from wheat rhizosphere in Iran. This study is the first report of A. tenuissima, B. cinerea, C. inaequalis, E. chlamydospora, F. avenaceum, F. chlamydosporum, F. scirpi, F. tricinctum, M. nivale (= F. nivale), P. circinata, P. chrysogenum and T. atroviride from Zanjan province. Also this is the first report of the pathogenicity of B. cinerea on wheat in Iran.

Biscogniauxia mediterranea, the cause of charcoal rot disease on oak, is known as one of the main agents involved in oak decline in Iran. However, very little is known on the extent of distribution, host range and mechanisms of dispersal of the pathogen in infected areas as well as incidence of the disease in other regions of country. The present study was aimed to develop a diagnostic tool for molecular identification and detection of the causal agent of charcoal rot disease based on species-specific primer set using polymerase chain reaction. To this aim, samples were collected from oak trees with typical charcoal rot disease from Ilam province. The causal agent was isolated and purified using routine plant pathology methods. Biscogniauxia isolates were identified using a combination of morphological and sequence data from ITSrDNA region. Blast search analysis of the sequence data obtained in this study against the sequence data in GenBank confirmed the identity of the isolates as B. mediterranea. Seqeunce data of ITS-rDNA region for all of Biscogniauxia were obtained from GenBank and aligned together with seqeunce data gnerated in this study. A pair of species-specific primer (BmF/BmR) with expcted amplicon size of 400 bp was designed for B. mediterranea. Efficacy of this primer set was tested and verified on DNA extracted from B. mediterranea and other fungal species isolated from oak tree tissues. The results of amplication profile showed that a 400 bp band was amplified only from B. mediterranea isolates. The species-specific primer set designed in this study can be used in monitoring programmes for the detection of the causal agent, the extent of distribution and mechanisms of dispersal of the pathogen.