ردیابی مولکولی ویروس موزاییک خیار (cmv) در مزارع زعفران شهرستان بشرویه

زعفران با نام علمی (crocus sativus l.) از خانواده زنبقیان  (iridaceae) یکی از گیاهان  زراعی مهم ایران است که از نظر اقتصادی و دارویی ارزش دارد. به منظور شناسایی ویروس موزاییک خیار روی زعفران ،148 نمونه ی دارای علائم زردی، کوتولگی، موزاییک و پیچیدگی برگ از مزارع زعفران شهرستان بشرویه طی آبان و آذر ماه سال 1401 جمع آوری گردید. آلودگی سه نمونه جمع آوری شده به ویروس موزاییک خیار با استفاده از آزمون زنجیره ای پلیمراز و با استفاده از یک جفت آغازگز اختصاصی مربوط به ژن پروتئین پوششی ویروس که قطعه ای به طول 657 جفت باز را تکثیر میکنند تایید شد.  نمونه ها جهت تعیین توالی به شرکت ماکروژن کره جنوبی ارسال شدند. بررسی های تبارزایی بر مبنای توالی ژن پروتئین پوششی ویروس با نرم افزارهای مرتبط به منظور تعیین جایگاه ویروس، انجام گردید. سه جدایه شناسایی شده از ویروس موزاییک خیار و سایر جدایه های موجود در بانک ژن در دو گروه تبارزایی و نزدیک به جدایه های یونان و کره جنوبی قرار گرفتند. این تحقیق اولین گزارش از وقوع این ویروس در مزارع زعفران شهرستان بشرویه می باشد.

detection and molecular investigation of cucumber mosaic virus (cmv) in saffron fields in boshruyeh city

introduction:saffron (crocus sativus l.) is a crucial crop in iran, celebrated for its medicinal and economic value. thriving in arid regions, it’s a perennial herb with corms used in food and pharmaceuticals. as the world’s priciest spice, it significantly impacts iran’s exports and industries, with a history in traditional medicine dating back 3000 years. over 90% of global saffron comes from iran, primarily khorasan razavi province (78%) and khorasan jonubi province (17%). saffron is also grown in fars, isfahan, and hamadan.boshrouyeh county in khorasan jonubi boasts saffron cultivation on 1,307 hectares in 2020-2021, yielding about 3.4695 tons, generating 70 billion tomans. regarding plant viruses, the cucumber mosaic virus (cmv) is a significant threat, affecting various plants globally, including cucumbers, tomatoes, and more. in iran, cmv has been reported in crops like bananas and melons, causing up to 20% yield loss.this study focuses on cmv in saffron plants in boshrouyeh county, using molecular methods for precise assessment due to its impact on saffron cultivation. materials and methods:in the autumn of 2022, a survey was conducted in saffron fields to assess virus symptoms like mosaic, stunting, yellowing, wrinkling, and leaf deformities. a total of 148 samples were collected, dried, and stored for analysis. rna was extracted from young plant leaves using a non-column rna extraction kit. specific viral protein coat primers were used for cdna synthesis, followed by pcr amplification. the pcr reaction involved denaturation at 94°c for 2 minutes, followed by 40 cycles at 94°c for 40 seconds, 52°c for 30 seconds, and 72°c for 2 minutes, with a final extension at 72°c for 5 minutes. electrophoresis confirmed three samples were infected with cmv. the amplified viral sequences were extracted and sequenced by a specialized company in south korea. sequence similarity was verified using blast tools on the ncbi database to confirm the presence of these virus strains and assess their genetic relatedness to global strains.results and discussion: in collected plant samples, various symptoms such as curling, leaf complexity, leaf mosaic, yellowing, and discoloration were observed. to conduct phylogenetic studies, three isolates of cucumber mosaic virus (cmv) from saffron fields in raghe and boshrouyeh were sequenced. sequence comparisons using blast revealed all three isolates shared similarity with cmv. a phylogenetic tree based on the 657-nucleotide coat protein gene sequence was constructed. analysis with megax software compared iranian isolates with 17 gene bank isolates. the resulting tree contained twelve branches, with iranian isolates showing the highest similarity to syrian and greek isolates. specifically, kho1 had the most significant similarity with 100% to tocmv5-1 from syria and 98% to pocmv9-11, also from syria. kho2 had the highest similarity of 98% with cmv-grcl1 from greece. kho3 showed 99% similarity to tocmv5-1 and 99% to kho1, both from different regions. these findings highlight the genetic diversity of cmv in saffron plants.