نوع مقاله : مقاله کامل علمی پژوهشی
نویسندگان
1 دانشگاه علوم کشاورزی و منابع طبیعی گرگان
2 دانشیار بیوتکنولوژی جنگل، دانشکده علوم جنگل، دانشگاه علوم کشاورزی و منابع طبیعی گرگان.
3 دانش آموخته دکتری علوم جنگل، دانشکده علوم جنگل، دانشگاه علوم کشاورزی و منابع طبیعی گرگان.
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
Background and objectives: Golestan province located in the eastern part of northern forests of Iran has a wide geographical distribution of Quercus castaneifolia in terms of rainfall, temperature and soil type. Climatic gradients from the west to the east of Golestan province have different impacts on the genetic and the ecotype diversity of tree populations in time that knowing the amount of this diversity helps us to manage/maintain the genetic structure of these species. The genetic diversity of trees is so important for adaptation of forests to climate change and for sustaining other species and entire forest ecosystems. The aim of this research is exploring the ecotypic diversity changes of Quercus castaneifolia populations in drought gradient (western-eastern) of Golestan province.
Materials and methods: To do the study, four different populations of Quercus castaneifolia from West to East of Golestan province in habitat areas of Tuskestan, Aliabadekatul, Loveh and Golidagh were selected. First, about 100 bases of Quercus castaneifolia with similar diameter and healthy and with approximately 50 to 100 meters distance from each other to avoid the possible affinity in each population were considered and then 20 bases of Quercus castaneifolia among them were randomly selected. After sampling qualitative study of marker peroxidase of the organ of biennial branch in four different populations was done by the use of vertical electrophoresis and by the method of Poly Acrylamide Gel Electrophoresis (PAGE). To analyze the data, scoring of bands into zero and one respectively for the absence and presence of bands was done based on the prepared gels. Then respective software packages were used to cluster analysis, Principle Coordinate Analysis as well as data analysis regarding the allelic characteristics of studied marker including the number of observed alleles, effective alleles, Shanon,s information index, hetrozygosity and polymorphic percentage and ecotype diversity within and among populations.
Results: The results of this research based on total, observed, effective alleles and hetrozygosity of the peroxidase marker showed that ecotype diversity and genetic diversity parameters examined in the western-eastern gradient of the different habitats of Golestan province is different and in the distant past, the genetic flow has been established through adjacent populations so that ecotypes are not separable.
Conclusion: To manage the maintenance and development of the genetic diversity of these stands, at first it is necessary to stabilize the present condition with respect to the diversity through emphasizing and maintaining the index bases inside the populations and helping their regeneration and secondly, developing the present diversity to combat the climate change threats through gene flow with the help of seed and seedling transition from the adjacent populations.
کلیدواژه‌ها [English]
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