نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه علوم گیاهی و بیوتکنولوژی، دانشکده علوم و فناوری زیستی، دانشگاه شهید بهشتی، تهران، ایران

2 مرکز تحقیقات ایمونولوژی، آسم و آلرژی، دانشگاه علوم پزشکی تهران، تهران، ایران

10.52547/envs.2021.1012

چکیده

سابقه و هدف: داده ­های علم گرده­ شناسی، در علوم متنوعی چون سیستماتیک­ گیاهی، گرده ­شناسی عسل شامل بررسی و ارزیابی کیفیت وخلوص عسل، گرده­ شناسی هوا، چینه ­شناسی، پزشکی­ قانونی، آب­ و­هواشناسی دیرینه، بازسازی پوشش­ های گیاهی دیرین، پیش­ بینی و شبیه ­سازی وقایع اقلیمی گذشته و پیش بینی وقایع اقلیمی آینده، باستان ­شناسی، رده ­بندی و فیلوژنی و شناسایی حساسیت­ های فصلی، کاربرد دارد. به ­دلیل آن که بسیاری از گونه ­های گیاهی کاشته ­شده و زینتی در گروه عامل­ های آلرژی­ زا محسوب می­ گردند و با توجه به اینکه مطالعات کمی پیرامون گرده شناسی با رویکرد آلرژی­ زایی در ایران تحقق یافته است، بنابراین انجام یک مطالعه گرده ­شناسی و تهیه بانک اطلاعاتی گرده­ شناسی شهر تهران از اهمیت پایه ­ای در مطالعات آلرژی برخوردار است. هدف­ های این مطالعه بررسی صفات ریخت ­شناسی و ریزریخت­ شناسی، طبقه بندی و تهیه بانک اطلاعاتی گرده ­شناسی گونه ­های علفی و درختچه ­ای کاشته­ شده شهر تهران به روش میکروسکوپ الکترونی است.
مواد و روش ­ها: شهر تهران با مساحتی حدود 600 کیلومترمربع به ­دلیل قرار گیری در دامنه ­های جنوبی البرز، وسعت جغرافیایی و قرارگیری در یک شیب ارتفاعی گسترده از شرایط اقلیمی متنوعی برخوردار است که در برگیرنده گونه­ های متنوع زینتی است. بنابراین با بررسی فلورهای چاپ شده و اطلاعات سازمان فضای سبز شهر تهران لیستی از گونه­ های تأثیرگذار و فراوان تهیه شد. سپس نمونه­ های گیاهی مورد نظر از رویشگاه­ های گیاهی جمع آوری و براساس روش ­های استاندارد، آبگیری و تثبیت شدند. سپس گونه­ های گیاهی با استفاده از فلورهای ایران و ایرانیکا شناسایی شدند. در نهایت دانه‌های گرده جدا شده از بساک را روی پایه‌های مخصوص میکروسکوپ الکترونی قرار داده و پس از پوشش دادن نمونه‌ها با فلز طلا با میکروسکوپ الکترونی نگاره[i] عکسبرداری شدند. سپس دانه­ های گرده براساس منابع معتبر گرده­ شناسی طبقه ­بندی و توصیف گردیدند.
نتایج و بحث: نتایج این مطالعه شامل تهیه یک منبع مدون تصویری بومی پیرامون دانه گرده 145 گونه درختچه ­ای و علفی کاشته شده شهر تهران می­ باشد. این 145 گونه گیاهی متعلق به 65 خانواده گیاهی شامل 95 گونه علفی و 50 گونه درختچه ­ای هستند. خانواده آفتابگردان با 16 گونه و خانواده گلسرخیان با 14 گونه، بیشترین نمونه­ ها را دارا هستند. از 131جنس مورد بررسی، 43 جنس آلرژی­ زا گزارش شده ­اند که خانواده آفتابگردان با دارا بودن 5 جنس آلرژی­ زا و سپس خانواده ­های سرو و زیتون با 3 جنس آلرژی­ زا بیشترین فراوانی گونه­ های آلرژی­ زا را در بین خانواده ­های مورد بررسی دارند. نتایج این مطالعه نشان می ­دهد که درختچه­ های آلرژی­ زا فراوانی بیشتری نسبت به گیاهان علفی آلرژی ­زا دارند. این در حالی است که درختان و درختچه ­ها به ­دلیل تولید گرده فراوان تر و گرده ­افشانی با باد دارای تأثیرهای آلرژی­ زای بیشتری هستند. دانه­ های گرده­ این گونه ­ها به ­طور معمول کوچک بوده و می ­توانند در مسافت­ های طولانی پراکنده شوند و از ماندگاری بیشتری در هوا برخوردارند. نتایج این مطالعه نشان می ­دهد که گرده ­های آلرژی­ زا نیز از تنوع ریختی بالایی برخوردارند البته تأثیر معنادار ریز ریخت شناسی دانه گرده در ایجاد آلرژی به مطالعات گسترده ­تری نیاز دارد.
نتیجه گیری: دستاوردهای این مطالعه به ­عنوان یک الگو جهت مطالعات گرده شناسی و بویژه در پژوهش ­های آسم و آلرژی در کشور کاربرد خواهد داشت. همچنین این مطالعه در راستای تکمیل بانک اطلاعات گرده ­ای و اطلس گرده ­شناسی کشور انجام می­ گردد. نتایج این مطالعه نشان می ­دهد که در شهر تهران گونه ­های گیاهی زیادی بدون در نظر گرفتن ملاحظات آلرژی ­زایی کاشته شده که به ­عنوان یک هشدار مهم جهت مدیران اکولوژی شهر باید مد نظر قرار گیرد.

کلیدواژه‌ها

عنوان مقاله [English]

Ecology and pollen database of shrub and cultivated herbaceous plant species in Tehran: An ecological management and urban safety approach

نویسندگان [English]

  • Safa Gohari 1
  • Ahmadreza Mehrabian 1
  • Raheleh Shokouhi Shoormasti 2

1 Department of Plant Sciences and Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University,Tehran, Iran

2 Immunology, Asthma and Allergy Research Institute Tehran University of Medical Sciences, Tehran, Iran

چکیده [English]

Introduction: Palynology as a multidisciplinary science can provide data base for a wide range of sciences such as Plant Systematics, Melissopalynology (quality control of honey), Aeropalynology, Stratigraphy, Palynology, Forensic Palynology, Paleoclimate, prediction and simulation of past climatic events, Archaeology, phylogeny, etc. Because several cultivated and ornamental species are classified as allergenic plants, identification, classification, and preparation of their database have particular importance. So far, few studies has been carried out on palynology in Iran. Therefore, it seems that carrying out a palynological study and preparing its database in Tehran is the first step in allergy research. The objectives of this study were to investigate the morphological and micro-morphological characteristics and classification, as well as preparing palynological database in Tehran.
Material and methods: Tehran has an area of about 600 km2 due to its location on the southern slopes of the Alborz Mountainous Region, widely extended along north to south and east to west zones, therefore showing a variety of climatic conditions that include diverse species (e.g., ornamental, etc.). So, after reviewing the published flora and present information on green space databases in the area, target taxa were selected. The plant samples were collected by field samplings and were deposited based on standard methods. Finally, the pollen grains were coated with gold material. Then, they were scanned with Scanning Electron Microscopy (SEM). Afterward, they were identified by diverse pollen references on palynology.
Results and discussion: The results of this study include the preparation of a native visual source about the pollen grains of 145 species of shrubs and cultivated herbaceous plant species in Tehran. These 145 plant species belong to 65 families, including 95 herbaceous species and 50 shrub species. Asteraceae (16 species) and Rosaceae (14 species) had the most species. Among the 131 studied genera, 43 genera were reported to be allergic. Asteraceae with 5 genera and Cupressaceae and Oleaceae with 3 genera had the highest frequency of allergenic species among the studied families. The results of this study showed that allergenic shrubs are more abundant than allergenic herbaceous plants. However, trees and shrubs have more allergenic effects due to more pollen production and wind pollination. The pollen grains of these species are usually small and can be scattered over long distances and have a longer durability in the air. The results of this study show that allergic pollens also have a high morphological diversity, however, the significant effect of pollen grain micro-morphological characteristics on allergies requires more extensive studies.
Conclusion: The achievements of this study will serve as a pilot for the study of palynological study, especially in asthma and allergy in the country. The results of this study show that in Tehran, several plant species have been planted without considering allergenic considerations, which should be considered as an important warning for ecological managers of the city.

کلیدواژه‌ها [English]

  • "Aeropalynology"
  • "Asthma and Allergy"
  • "Polynological Database"
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