اثرتنش آبی بر صفات فیزیولوژیک و فیتوشیمیایی گیاه دارویی خارمریم (Silybum marianum L.)

نوع مقاله : مقالات پژوهشی

نویسندگان

1 دانشجوی دکترا، گروه علوم باغبانی، دانشکده کشاورزی و منابع طبیعی ، دانشگاه محقق اردبیلی

2 محقق اردبدانشیار، گروه باغبانی، دانشکده کشاورزی و منابع طبیعی، دانشگاه محقق اردبیلییلی

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

4 استادیار ، گروه بیوتکنولوژی مولکولی گیاهی، پژوهشگاه ملی مهندسی ژنتیک و بیوتکنولوژی.

5 دانشیار، گروه زراعت و اصلاح نباتات، دانشکده کشاورزی و منابع طبیعی، دانشگاه محقق اردبیلی

10.22067/jhs.2021.68962.1022

چکیده

عوامل محیطی از یک طرف باعث تغییراتی در رشد گیاهان دارویی و از طرف دیگر موجب تغییر در مقدار و کیفیت مواد موثره آن‌ها می‌گردند. در این آزمایش اثر تنش آبی (آبیاری کامل در حد ظرفیت زراعی؛ بدون تنش، آبیاری در حد 70 درصد ظرفیت زراعی؛ تنش ملایم و آبیاری در حد 40 درصد ظرفیت زراعی؛ تنش شدید) بر صفات فیزیولوژیک، میزان سیلی‌بین a و b و وزن هزار دانه در گیاه دارویی خارمریم در سال‌های 1396-1397 در مزرعه تحقیقاتی دانشگاه شهیدبهشتی بررسی شد. این آزمایش در قالب طرح بلوک‌های کامل تصادفی با 3 تکرار انجام شد. تنش آبی در مرحله گلدهی و به روش وزنی اعمال شد. نتایج حاصل نشان داد با افزایش شدت تنش آبی، مقدار سیلی‌بین a و b به ترتیب به میزان 24 و 26 درصد افزایش پیدا کرده است که مقدار این ترکیبات در تیمار آبیاری 40 درصد ظرفیت زراعی بطور قابل‌توجهی بالاتر از سایر تیمارها بود، بطوریکه مقدار آن نسبت به تیمار ظرفیت زراعی (mg/g Grain DW 07/26 در سیلی بین a و mg/g Grain DW 74/40 در سیلی بین b) و نسبت به تیمار 70 درصد ظرفیت زراعی (mg/g Grain DW 32/25 در سیلی بین a و mg/g Grain DW 64/34 در سیلی بین b) بیشتر بود. این امر حاکی از اختصاص بیشتر کربن تثبیت شده حاصل از فتوسنتز جهت تولید متابولیت‌های ثانویه در این تیمار بود. همچنین مقدار سیلی‌بین b نسبت به سیلی‌بین a در تمامی تیمارها به نسبت 2/1 (سیلی‌بین b) : 8/0 (سیلی‌بین a) بود. در تیمار 40 درصد ظرفیت زراعی مقدار سیلی‌بین a و b (به ترتیب 30/67 و 92/98 میلی‌گرم در گرم وزن تر) بطور قابل‌توجهی نسبت به سایر تیمارها افزایش داشت. بیشترین فعالیت آنزیم کاتالاز (U/ml 16/5) و آسکوربات پراکسیداز (U/ml 26/2) در تیمار تنش ملایم مشاهده شد. محتوای پرولین با افزایش شدت تنش به تدریج افزایش یافته و میزان آن در تنش شدید به حداکثر خود رسید (36/3 میکرومول بر گرم وزن تر). پراکسیداسیون لیپید در تنش شدید (40 درصد ظرفیت زراعی) بیشترین مقدار خود را داشت (nmol/grFW 35/8). وزن هزار دانه بذر نیز در تیمار تنش شدید (تیمار 40 درصد ظرفیت زراعی) نسبت به کنترل (تیمار ظرفیت زراعی) به میزان 8/6 گرم کاهش پیدا کرد. با توجه به نتایج آزمایش به نظر می‌رسد که می‌توان با اعمال شیوه کم آبیاری، میزان فلاونوئیدهای گیاه خارمریم را به منظور اهداف دارویی از جمله درمان بیماری‌های کبدی و انواع هپاتیت افزایش داد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of Water Stress on Physiological and Phytochemical Parameters of Milk Thistle (Silybum marianum L.)

نویسندگان [English]

  • Rahele Ghanbari Moheb Seraj 1
  • mahdi behnamian 2
  • Asadollah Ahmadikhah 3
  • Vahid Shariati 4
  • sara dezhestan 5
1 PhD candidate, Department of Horticultural Sciences, Faculty of Agricultural Sciences, University of mohaghegh ardabili, Ardabil, Iran.
2 Associate Professor, Department of Horticultural Sciences, Faculty of Agricultural Sciences, University of mohaghegh ardabili, Ardabil, Iran
3 Department of Biotechnology, Faculty of Biological Sciences and Technology, Shahid Beheshti University, Tehran, Iran
4 Assistant Professor, Department of Plant Molecular Biotechnology, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.
5 Associate Professor, Department of Agriculture and Plant Breeding, Faculty of Agricultural Sciences, University of mohaghegh ardabili, Ardabil, Iran.
چکیده [English]

Introduction Plant growth and yield are affected often by stress conditions, especially drought, which is the most important factor in reducing crop production worldwide. Silybum marianum is an important pharmaceutical crop with great potential as a multipurpose plant for low-input cropping systems of the arid and semiarid regions.
Materials and Methods In this experiment, the effect of drought stress (full irrigation at field capacity; no stress, irrigation at 70% of field capacity; mild stress and irrigation at 40% of field capacity; severe stress) on physiologic traits, the amount of silybin a and b and 1000 seed weight in milk thistle was studied in the research field of Shahid Beheshti University in 2017-2018. The experimental site is located in Shahid Beheshti University, Tehran, Iran (51.23°N, 35.48°E, and 1769 m above mean sea level). It has a moderate and mountainous climate with a mean annual rainfall of 145.2 mm and a mean temperature of 22ºC. This experiment was performed in a completely randomized block design with 3 replications. Milk thistle seeds were prepared from Isfahan Pakanbazr Company. The soil composition consisted of 1/3 clay, 1/3 sand, and 1/3 leaf composts. The field area was 150.0 m2. Furrows were created to implement this study. The space of plants on rows was 0.5 m and between rows was 1 m. In general, 15 furrows were created and 15 plants were cultured on each furrow, so the total number of plants cultivated on the field was 225. Drought stress was applied at flowering stage. Soil moisture was measured by the weighing method. The soil samples were taken from various areas (randomly) of the field, three samples each day. After measuring the water content at F.C, based on that, the amount of 70%F.C and 40%F.C was also calculated. At the time of stress, F.C irrigation was performed every two days, 70% F.C irrigation every 4 days, and 40% F.C irrigation every 6 days. After 8 days, leaf sampling was performed to measure catalase, ascorbate peroxidase, proline and malondialdehyde content and seed sampling was performed to 1000 seed weight and extract analysis. For physiologic measurements, 3 plants were randomly assigned to each stack and their leaves were separated and transferred to the laboratory. Then, in the next step, their physiologic parameters (include Catalase and ascorbate peroxidase, proline and malondialdehyde content) were measured according to the relevant protocol. In order to measure silybin, 4 plants were randomly considered to each stack and their seeds were harvested and combined and dried in shade condition in the laboratory for one month. The dried seed samples were completely powdered using a mill, then 10 g of the powders weighed and the oil extract of them was isolated by Soxhlet using n-hexane solvent. The extraction temperature was 70 °C and the extraction time was 6 h. After the extraction was completed, the extract was poured into dark glass. Next, the oil-free powder was dried in an incubator at 37 ° C. Methanol extract of oil-free powder was extracted using methanol solvent. For this purpose, 2 g of samples powder was weighed and 200 ml of 80% methanol was added to each of them and the mixture stirred for two days by Shaker. The mixture was then passed from a filter paper and after that, 200 ml of 80% methanol was added to the sample precipitate (on filter paper) and placed again on the shaker. After 24 h, extraction was performed by the same method and were added to the previous extract. The extracts were then concentrated in the environment temperature for two weeks. Concentrated extracts (powder) as well as standard silymarin with certain concentrations were dissolved in methanol solvent and used for injection into HPLC (Model: Infinity1260, Manufacturer: Agilent) using syringe filters with a diameter of 0.2 μm. After receiving the HPLC results, the data and peaks were analyzed and the amounts of silybin a and b were determined and compared at different levels of water stress. Statistical analysis of data was performed using R 3.6.1 and RStudio 1.1.463 software. Mean data were compared using Duncan's test with agricolae package at a significance level of 0.05.
Results and Discussion The results showed that with increasing water stress intensity, the amount of silybin a and silybin b increased by 24% and 26%, respectively. The amount of these compounds in 40% were significantly higher than other treatments, so that its amount compared to F.C treatment (26.07 mg/g Grain DW in silybin a and 40.74 mg/g Grain DW in silybin b) and compared to the 70%F.C (25.32 mg/g Grain DW in silybin a and 34.64 mg/g Grain DW in silybin b) was higher. This indicates carbon assimilation from photosynthesis to produce secondary metabolites in this treatment. Also, the amount of silybin b compared to silybin a in all treatments was (0.8: 1.2), in which 1.2 is related to silybin b and 0.8 is related to silybin a. In severe stress treatment (40% of field capacity), the amount of silybin a and b (67.30 and 98.92 mg/g, respectively) increased significantly compared to other treatments. According to the mean comparison results, the highest activity of catalase (5.16 U/ml) and ascorbate peroxidase (2.26 U/ml) was observed in mild stress treatment. Proline content gradually increased with increasing stress intensity and reached its peak in severe stress (3.36 µM/gr). Lipid peroxidation also had their maximum in severe stress (8.35 nmol/grFW). The 1000 seeds weight was reduced by 6.8 g in severe stress treatment (40%F.C) compared to the control (F.C).
Conclusions According to the results, the amount of milk thistle flavonoids can be increased for medicinal purposes including the treatment of liver disease and hepatitis by applying dehydration stress.

کلیدواژه‌ها [English]

  • drought
  • HPLC
  • Methanol extract
  • Silymarin
  • Soxhlet

مقالات آماده انتشار، پذیرفته شده
انتشار آنلاین از تاریخ 23 تیر 1400
  • تاریخ دریافت: 29 بهمن 1399
  • تاریخ بازنگری: 20 تیر 1400
  • تاریخ پذیرش: 23 تیر 1400