افزایش ترکیبات فنلی برگ زیتون (Olea europaea L.) با کاربرد خاکی کودهای شیمایی و آلی

نوع مقاله : پژوهشی

نویسندگان

1 استادیار مؤسسه تحقیقات جنگلها و مراتع کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، تهران، ایران

2 دکتری مؤسسه تحقیقات جنگلها و مراتع کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، تهران، ایران

چکیده

سابقه و هدف: برگ‌های درخت زیتون حاوی ترکیباتی با کاربرد دارویی قابل‌توجه هستند. برگ‌های زیتون حاوی مقادیر زیادی از ترکیبات فنلی از جمله اسیدهای فنلی، فلاونوئیدها، فنیل پروپانوئیدها و سکوریدویدها می‌باشند. اولئوروپین (ترکیب سکوریدویدی) به عنوان ترکیب فنلی فعال در برگ‌های زیتون شناخته می‌شود. پژوهش‌های اندکی به بررسی تأثیر کوددهی بر ترکیب‌های بیوشیمیایی برگ‌های زیتون پرداخته‌اند. بنابراین، پژوهش حاضر با هدف بررسی تغییرات ویژگی‌های مورفولوژیک، عناصر معدنی، محتوی اولئوروپین و کوئرستین در برگ‌های زیتون تغذیه شده با کودهای شیمیایی و آلی اجرا شد.
مواد و روش‌ها: تأثیر تیمارهای مختلف کود شیمیایی (NPK) و آلی (اسید هیومیک و فلوویک) بر ویژگی‌های رقم زیتون زرد، به صورت دو آزمایش جداگانه در قالب طرح بلوک‌های کامل تصادفی با سه تکرار در سال زراعی 1392، انجام شد. تیمارهای آزمایش کود شیمیایی شامل پنج سطح کود NPK (صفر، 50، 100، 150و 200 کیلوگرم در هکتار) و تیمارهای آزمایش کود آلی شامل شش سطح ترکیب آلی اسید هیومیک و فلوویک (صفر، 5، 5/7، 10، 5/12 و 15 لیتر در هکتار) بود.
یافته‌ها: نتایج کودهای شیمیایی نشان داد که بیشترین ارتفاع بوته با 7/117 سانتی‌متر و شاخه فرعی با 34 شاخه به‌ترتیب در تیمار N200P200K200 و N100P100K100 کیلوگرم در هکتار مشاهده شد. بیشترین تعداد برگ از کاربرد 10 لیتر در هکتار کودهای آلی به‌دست آمد. تأثیر تیمارهای NPK بر ترکیبات فنلی برگ زیتون، نشان‌ دهنده افزایش 30 و 80 درصدی مقدار اولئوروپین و کوئرستین به‌ترتیب در سطح N100P100K100 و N200P200K200 کیلوگرم در هکتار نسبت به تیمار شاهد بود. اثر کودهای آلی هم، تنها بر مقدار کوئرستین معنی‌دار بود و بیشترین مقدار آن (7/397 میکروگرم بر گرم) در تیمار 10 گرم در لیتر اندازه‌گیری شد. تأثیر سطوح کودهای شیمیایی بر همه‌ی عناصر درشت و ریز مغذی اندازه‌گیری شده به‌جز پتاسیم معنی‌دار بود و بیشترین مقادیر اندازه‌گیری شده این عناصر در سطح تیماری N200P200K200 کیلوگرم در هکتار به‌دست آمد. اثر سطوح کودهای آلی بر عناصر منیزیم، منگنز، روی و مس معنی‌دار بود.
نتیجه‌گیری: کاربرد کودهای آلی مانند اسید هیومیک و فلوویک در کنار کود‌های شیمیایی می‌تواند موجب بهبود ویژگی‌های ریخت‌شناسی، فراهمی عناصر غذایی مورد نیاز گیاه و افزایش ترکیبات فنلی برگ زیتون شود.
برگ‌های زیتون (Olea europaea L.) حاوی ترکیبات فنلی از جمله اسیدهای فنلی، فلاونوئیدها، فنیل پروپانوئیدها و سکوئیریدوئیدها هستند که به عنوان منبع مهم ترکیبات زیست فعال بدون نیاز به مصرف مقادیر بالایی از روغن زیتون محسوب می‌شوند (35). تغییرات بیوشیمیایی بافت‌های گیاهی به طور معمول تحت تأثیر ژنتیک، تغییرات فیزیولوژیک و محیط قرار دارد. مقدار ترکیبات فنلی برگ زیتون نیز تحت تأثیر عواملی مانند ژنوتیپ (54)، سن برگ (42)، تغذیه (70)، مرحله رشدی (42)، شیوه استخراج (68) و تنش‌های زیستی و غیرزیستی (4 و 68) قرار دارد.

کلیدواژه‌ها


عنوان مقاله [English]

Enhancement of phenoilc compounds of olive (Olea europaea L.) leaf with soil application of chemical and organic fertilizers

نویسندگان [English]

  • Bohlul Abbas zadeh 1
  • Samaneh Asadi Sanam 1
  • Masoumeh Layegh Haghighi 2
1 Assistant Prof., Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran,
2 Ph.D., Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
چکیده [English]

Background and objectives: Olive tree (Olea europaea L.) leaves are a very promising and unique herbs source which have considerable therapeutic applications. Olive leaves contain high amounts of phenolic compounds such as phenolic acids, flavonoids, phenylpropanoids and secoiridoids. Oleuropein (secoiridoid compound) is considered as the main active phenolic compound in olive leaves. Fewer studies are dedicated to the effects of fertilization on the chemical composition of olive leaves. Therefore, the current study aimed to investigate the associated changes in morphological characteristics, mineral profile and oleuropein and quercetin contents in olive leaves fertilized with chemical and organic fertilizers.
Materials and methods: In order to evaluate the effect of different treatments of chemical and organic fertilizers (humic and fluvic acid) on morphological characteristics, macro- and micronutrient elements as well as phenolic compounds (oleuropin and quercetin) of Zard cultivar, two separate experiments were conducted in a randomized complete block design with three replications in the 2013 crop year. The treatments included application of five levels of NPK (0, 50, 100, 150 and 200 kg ha-1) and six levels of humic acid and fluvic acid (0, 5, 7, 10, 12.5 and 15 liters ha-1).
Results: The results of chemical fertilizers showed that the highest plant height (117.7 cm) and branches number (34 branches) showed in N200P200K200 and N100P100K100 kg ha-1, respectively. The most leaves (60 leaves) were obtained in application of 10 liters per hectare of organic fertilizers. Compared to the control, application of 100 and 200 kg ha-1 NPK showed an increase of 30 and 80% of the oleuropine and quercetin content, respectively. The effect of organic fertilizers was only significant on quercetin content, and its maximum (397.7 μg g-1) was measured in 10 g liters-1 treatment. Effect of chemical fertilizer levels on all measured macro- and micronutrients except potassium was significant and the highest measured values of the elements were obtained at N200P200K200 kg ha-1 level. The effect of organic fertilizers levels on magnesium, manganese, zinc and copper content was also significant.
Conclusion: The application of organic fertilizers such as humic and fluvic acid along with chemical fertilizers can improve the morphological characteristics, provide the nutritional requirements of the plant and increase the phenolic compounds of olive leaves.
Conclusion: The application of organic fertilizers such as humic and fluvic acid along with chemical fertilizers can improve the morphological characteristics, provide the nutritional requirements of the plant and increase the phenolic compounds of olive leaves.

کلیدواژه‌ها [English]

  • Fluvic acid
  • Humic acid
  • Oleuropein
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