نوع مقاله : علمی- پژوهشی
نویسندگان
1 عضو هیئت علمی موسسه تحقیقات جنگلها و مراتع کشور
2 کارشناس پژوهشی موسسه تحقیقات جنگلها و مراتع کشور
3 کارشناس پژوهشی مرکز تحقیقات منابع طبیعی و امور دام استان گیلان
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
This research was done at two different altitude level of two northern provinces (Gilan & Mazandaran). The altitude levels for Mazandaran province were 80 and 1100 meter above sea level (coastal, low, moderate and high level, respectively). After studying the environmental parameters and writing down their data, the individual trees of Fraxinus excelsior at each sample plot were selected. The environmental studies and their ecological factors indicated that the most of Fraxinus excelsior seeds were hallow due to destroying of natural forest ecosystems. Natural regeneration was not found because of overgrazing by livestacks. Sampling was done from male and female from flower sprouting to seed ripening stages, monthly. The investigation was carried out for 3 consecutive years (1996-1998). The samples were extracted then qualitative and quantitative alterations of proteins and enzyme (peroxidase) were studied by polyacrylamide gel electrophoresis (PAGE) and spectrophotometric methods, respectively. Alterations of Na+ , Ca2+ .K+ were measured by flamephotometric method. Results indicated qualitative and quantitative alterations of proteins, enzyme and peroxidase isoenzymes during sampling. Sprouts had the minimum izoenzymatic bands, peroxidase activity and protein content. During the Thir and Mordad months proteins and peroxidase activity were maximum qualitatively and quantitatively. In rippened seeds peroxidase activity was minimum and izoenzymes were high molecular weight ones. The number of izoenzymes were minimum at that time. Quantitative alteration of proteins was almost similar to the peroxidase alteration. During seed development contents of Na+, K+ and Ca2+ changed regularly. Alteration of sodium was more than K+ and Ca2+. This indicated that this element had an important role in the metabolic development of Fraxinus exelsiorseeds. Germination of seeds were studied under different condition such as seasonal sampling (beging and end of Shahrivar and Mehr months), storage at -8 and +4 centigrade degree for 15 days and nutrional treatment (distilled water and hydrogen peroxide). The best treatments were sampling at the end of Shahrivar( before seed color change), storageat -8 centigrade degree for 15 days and hydrogen peroxide treatment. Percent of germination increased from 0 (in control) to %100 in treated seeds.
کلیدواژه‌ها [English]
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