اطلاعات جدید از قارچ‌های تیره erysiphaceae (ascomycota: helotiales) از استان کهگیلویه و بویراحمد، ایران

نمونه‌های با علایم سفیدک سطحی از مناطق مختلف استان کهگیلویه و بویراحمد جمع‌آوری و برای شناسایی آنها خصوصیات مربوط به ساختارهای مختلف شامل کاسموتسیوم (قطر، شکل و ابعاد زواید اطراف آن)، آسک (شکل، ابعاد) آسکوسپور (تعداد در هر آسک، شکل، ابعاد)، سلول پایه کنیدیوفور (شکل، ابعاد) و کنیدیوم (منفرد یا زنجیری بودن، شکل، ابعاد) در چندین اسلاید میکروسکوپی بررسی و از این ساختارها ترسیم‌های مناسب با کمک لوله ترسیم متصل روی میکروسکوپ olympus ch30 انجام شد. گیاه  helichrysum oligocephalumدر حد جنس و گونه میزبان جدیدی برای جنس golovinomyces در ایران محسوب می‌شود. علاوه بر این، تا کنون گزارشی از سفیدک سطحی روی گیاه vicia narbonensis در ایران منتشر نشده است. برخی گونه‌ها اگرچه پیش از این از ایران معرفی شده‌اند، میزبان‌های گیاهی جدید برای آنها شناسایی شد. به این ترتیب گیاه bromus hordeaceus برای قارچ blumeria graminis species complex، گیاهان carduus pycnocephalus، cirsium syriacus و jurinea carduiformis برای قارچ golovinomyces montagnei، گیاهان erodium glauchophyllum و e. moschatum برای قارچ podosphaera erodii و گیاه geranium pyrenaicum برای قارچ podosphaera fugax به‌عنوان میزبان‌های گیاهی جدید عوامل مولد سفیدک سطحی در ایران معرفی می‌شوند.

recent discoveries about erysiphaceae (ascomycota: helotiales) in kohgiluyeh and boyer ahmad province, iran

this study involved the collection of samples exhibiting powdery mildew symptoms from various locations in kohgiluyeh and boyer ahmad province. these samples were then meticulously examined to identify specific characteristics related to various structures, such as casmothecium (including diameter, shape, and dimensions of appendages), sscus (shape, dimensions), ascospore (number per ascus, shape, dimensions), foot-cells of conidiophore (shape, dimensions), and conidium (solitary or catenate formation, shape, dimensions). this examination was conducted using multiple microscopic slides and detailed drawings of the structures were prepared using an olympus ch30 microscope equipped with a drawing tube. the study revealed that helichrysum oligocephalum represents a new host at the genus and species level for the genus golovinomyces in iran. additionally, it was noted that there were no previous reports of powdery mildew on vicia narbonensis in iran. furthermore, while some species had been previously documented in iran, new host plants were identified for them. for instance, bromus hordeaceus was identified as a new host for the blumeria graminis species complex and carduus pycnocephalus, cirsium syriacus, and jurinea carduiformis were found to be new hosts for golovinomyces montagnei. additionally, erodium glauchophyllum and e. moschatum were identified as new hosts for podosphaera erodii and geranium pyrenaicum was found to be a new host for podosphaera fugax. these findings introduced as new hosts of powdery mildew fungi in iran.introductionthe agents responsible for powdery mildew are significant pathogens and obligatory plant parasites with a broad host range. identification of these agents is based on the morphological characteristics of both the asexual stage (anamorph) and the sexual stage (teleomorph). kohgiluyeh and boyer ahmad province is renowned for its rich vegetation diversity, which enhances the likelihood of discovering new taxa of powdery mildews and their associated host plants. consequently, this research focused on examining plant samples from various locations within the province.numerous studies by iranian researchers on powdery mildews have been documented in various articles, including the works of pirnia (2014), sharifi et al. (2014), mirhosseini et al. (2015), darvishnia and vafaei (2018), abbasi et al. (2019), golmohammadi et al. (2019), pirnia and taheri (2020), and darsaraei et al. (2022). these findings have been summarized in two lists by khodaparast and abbasi (2009) and ershad (2022).the first comprehensive monograph of powdery mildews authored by braun in 1987 presented the names of 18 genera and 435 species. subsequently, in 2012, after reviewing numerous samples and molecular data, braun and cook accepted 16 genera and over 800 species as valid names for powdery mildews. furthermore, researchers from other countries have introduced new taxa and hosts through their studies. notable among these are the works of braun and mohan (2013), thite and kore (2014), tam et al. (2015), and wang et al. (2019). materials & methodssample collectionplant samples exhibiting powdery mildew symptoms were gathered from various regions in kohgiluyeh and boyer ahmad province. upon arrival at the laboratory, these samples underwent identification and confirmation by a botanist. examination of macro-morphological characteristicssamples displaying powdery mildew symptoms were scrutinized using a nikon stereomicroscope. location of fungal structures on the upper or lower surface of the leaves, density of mycelium, and the presence or absence of cosmothecium were meticulously documented.preparation of microscopic slides, identifying micro-morphological characteristics, and drawing of structuresmicroscopic slides were meticulously prepared from different structures in 25% lactic acid. the characteristics of these structures, including cosmothecium (diameter, type, and size of appendages around it), ascus (dimensions, presence or absence of a base), ascospore (dimensions, shape, number per ascus), basal cell of conidiophore (dimensions, shape), and conidium (size, shape, solitary or in chain), were examined using an olympus ch30 optical microscope. the dimensions of these structures were measured using a calibrated micrometer installed on the microscope. finally, the structures were accurately drawn using a drawing tube attached to the microscope.       research findingsintroduction of identified taxa blumeria graminis species complex fig 1. blumeria graminis species complex (a) casmothecium (scale: 50 µm), (b) ascus and ascospore, (c) conidiophore, and (d) conidium erysiphe cruciferarum  fig 2. erysiphe cruciferarum (a) conidiophore and (b) conidium erysiphe heraclei fig 3. erysiphe heraclei (a) casmothecium, (b) ascus and ascospore, (c) conidiophore, and (d) conidiumerysiphe sp.  fig 4. erysiphe sp. species complex (a) conidiophore and (b) conidium golovinomyces aff. asterum fig 5. golovinomyces aff. asterum (a) conidiophore and (b) conidium golovinomyces biocellatus species complex fig 6. golovinomyces biocellatus species complex (a) casmothecium, (b) ascus and ascospore, (c) conidiophore, and (d) conidiumgolovinomyces aff. bolayi  fig 7. golovinomyces aff. bolayi (a) casmothecium, (b) ascus and ascospore, (c) conidiophore, and (d) conidium    golovinomyces montagnei  fig 8. golovinomyces montagnei (a) casmothecium, (b) ascus and ascospore, (c) conidiophore, and (d) conidium     golovinomyces sp. fig 9. golovinomyces sp. (a) casmothecium, (b) ascus and ascospore, (c) conidiophore, and (d) conidium neoerysiphe galii fig 10. neoerysiphe galii (a) casmothecium, (b) ascus and ascospore, (c) conidiophore, and (d) conidium neoerysiphe nevoi fig 11. neoerysiphe nevoi (a) casmothecium, (b) ascus and ascospore, (c) conidiophore, and (d) conidiumpodosphaera dipsacacearum fig 12. podosphaera dipsacacearum (a) casmothecium, (b) conidiophore, and (c) conidium podosphaera erigerontis-canadensis  fig 13. podosphaera erigerontis-canadensis (a) casmothecium, (b) ascus and ascospore, (c) conidiophore, and (d) conidium podosphaera erodii fig 14. podosphaera erodii (a) casmothecium, (b) ascus and ascospore, (c) conidiophore, and (d) conidiumpodosphaera fugax  fig 15. podosphaera fugax (a) casmothecium, (b) ascus and ascospore, (c) conidiophore, and (d) conidium discussion of results & conclusionthe discovery of bromus hordeaceus l. as a new host for blumeria graminis in iran is noteworthy. additionally, the absence of reports of powdery mildew on vicia narbonensis l. in iran has led to the introduction of erysiphe sp. as the causal agent due to insufficient information.symphyotrichum subulatus michx., a member of the tribe astereae (asteraceae), has been associated with golovinomyces asterum as the causal agent of powdery mildew as indicated by takamatsu et al. (2013). furthermore, golovinomyces bolayi has been previously reported in iran on lactuca tuberosum jacq. (pirnia and taheri 2020). its host range within the asteraceae is limited to members of the tribe cichorieae (braun et al., 2019).the plant genera carduus l., cirsium mill., and jurinea cass., which belong to the tribe cardueae (asteraceae), have been identified as new hosts for g. montagnei in iran. similarly, helichrysum oligocephalum dc., a member of the tribe gnaphalieae (asteraceae), was examined in this research. although the exact taxonomic position of the powdery mildew agent on gnaphalieae is unknown, the sample was categorized under the name of golovinomyces sp.furthermore, neoerysiphe galli and neoerysiphe nevoi were new records for mycobiota in kohgiluyeh and boyer-ahmad province. additionally, erodium glaucophyllum (l.) l her. and erodium moschatum (l.) l her. were identified as new hosts for podosphaera erodii, while geranium pyrenaicum burm.f. was also considered a new host for podosphaera fugax in iran.