Medicinal Plants
M. Azizi; S. Beigi; Z. Safaei; M. Mansoori
Abstract
IntroductionMedicinal plants are economical important plants that are used in traditional medicine and industry as raw or processed materials. Valerian (Valeriana officinalis L.) is one of the important medicinal plants which belong to Valerianaceae family. The valerian rhizome and roots have been considered ...
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IntroductionMedicinal plants are economical important plants that are used in traditional medicine and industry as raw or processed materials. Valerian (Valeriana officinalis L.) is one of the important medicinal plants which belong to Valerianaceae family. The valerian rhizome and roots have been considered as a valuable medicinal plant that essential oil content (between 0.1 to 2 percent) varied according to climatic conditions of production location. Valerian needs a lot of water during the growth period and enough moisture around the roots and rhizome increase root yield. Iran is situated in an arid and semi-arid region. When a plant's minimum water requirement is not met, it experiences drought stress, which can cause severe and often irreversible damage to the crop. One effective method for improving irrigation efficiency under such conditions is the use of superabsorbent polymers. These hydrocarbon-based materials can retain large amounts of water or aqueous solutions in the plant root zone, thereby mitigating the negative effects of drought stress. Their application can enhance plant growth, extend irrigation intervals, reduce water loss, and lower irrigation costs. Generally, water efficiency, dry matter production and root development, are positive reactions to the use of superabsorbent. In this regard, Stockosorb® copolymer is potassium-based nutrients that have a high ability to absorb water and nutrients and high strength polymer maintained the water has been proven. The aims of this investigation were to study the effects of Stockosorb® hydrophilic polymers, on some morphological (root dry weight and yield, leaf area), biochemical (chlorophyll a, b), physiological (electrolyte leakage, leaf relative water content) characteristics and essential oil content and yield of valerian under drought stress. Materials and MethodsThis research was conducted in field (1×1 m2) at Department of Horticultural Science‚ College of Agriculture‚ Ferdowsi University of Mashhad. The research was set out in a factorial experiment based on completely randomized block design. The Stockosorb® hydrophilic polymer at four concentrations (0, 100, 200, 300 gr/m2) and two irrigation period (6 and 10 day) with three replications were set as treatments and leaf area, root dry weight and yield, chlorophyll a, b, electrolyte leakage, leaf relative water content and essential oil content and yield were evaluated at the end of the growth period. The seeds of Valeriana officinalis were sown in protected open field for seedling production and the seedling were transplanted to the field at four-leaf stage (10 plant per plot). Stockosorb® mixed with soil, after weighing the polymers based on determined concentration. After seedling establishment, all plots were irrigated with a determined amount and equal of water. Results and DiscussionThe results showed, using Stockosorb® superabsorbent polymer be useful for water supply the plant in water stress condition. Application of this substance on some morphological, biochemical and physiological characteristics and valerian essential oil, was significant at 1% and superior to the control. According to the results obtained, Stockosorb® 300 g.m-2 with irrigation period 6 days interval, increased leaf area, root dry yield, leaf relative water content, chlorophyll a and essential oil yield. While, the highest valerian root dry weight and essential oil content were obtained with application of Stockosorb® 200 g.m-2 and irrigation period of 6 days interval. The highest electrolyte leakage was related to control and irrigation period 10 days interval and the maximum chlorophyll b was belonged to Stockosorb® 100 g.m-2 with irrigation period 10 days interval. ConclusionsSince the ultimate goal in cultivating valerian, as with other essential oil-bearing plants, is to optimize both yield and essential oil content, the findings of this study recommend the application of 300 g/m² Stockosorb polymer combined with a 6-day irrigation interval. This approach effectively mitigates drought stress and enhances all evaluated growth and yield characteristics in valerian.The highest root dry weight under drought stress was related to more accessible and preservatives water in characteristics the root zone and it found by using the middle concentrations (200 gr/m2) super absorbent polymer and irrigation period shorter (6 day). Using of mentioned treatments, according to the middle water stress, leads to increased valerian essential oil. The best root dry yield, essential oil yield, electrolyte leakage, chlorophyll a and %RWC with sufficient amounts of water and better growth conditions were achieved by application of 300 g.m-2 Stockosorb® and irrigation period 6 days interval. In general, superabsorbent polymer was able to increase irrigation period and this was evident in qualitative and quantitative results related to the valerian in the treatment of 300 gr/m2 with irrigation period 10 day and 100 g.m-2 of polymer 6 day irrigation period. The results showed that superabsorbent polymers can enhance plant performance by influencing plant metabolic processes and providing protection against environmental stresses. Their application reduces the adverse effects of stress, contributing to the preservation and improvement of the plant's economic yield.
Sonayye Beigi; Majid Azizi; Seyyed Hossein Nemati; Vahid Rowshan
Abstract
Introduction: Medicinal plants are rich in active substances and primarily have been used in the manufacture of many drugs. Basil (Ocimum basilicum L.) is one of the important medicinal plants whichbelongs to the Lamiaceae family. Basil essential oil content (between 0.5 to 1.5 percent) varies according ...
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Introduction: Medicinal plants are rich in active substances and primarily have been used in the manufacture of many drugs. Basil (Ocimum basilicum L.) is one of the important medicinal plants whichbelongs to the Lamiaceae family. Basil essential oil content (between 0.5 to 1.5 percent) varies according to climatic conditions of habitat location. Basilneeds a lot of water during growth period and it is very sensitive to water stress and shows wilting symptoms very soon after water shortage. Iran is located in an arid and semi-arid region which has little precipitation that is not enough for crop water requirements. Nowadays, the use of superabsorbent polymers is one of the ways to create sustainable agriculture and increase irrigation efficiency. They can store high water or aqueous solutions in root zone of plants and to reduce negative effects of drought stress. So, improvement of plant growth, increasing of irrigation intervals, reducing water loss and costs of irrigation is due to the application of superabsorbent polymers. Mucilages are also the herbal polysaccharides, soluble in water, and commonly include carbohydrates and can be used as hydrophilic polymers. The aims of this investigation were to study the effects of hydrophilic polymers on water use efficiency, morphological characteristics (dry matter, leaf area, and leaf number), essential oil quantity and yield of basil to harden plant to drought stress and to evaluate its potential to cultivate in arid regions. In addition, taking steps forward towards sustainable agriculture, by reducing the cost of agricultural production, helps protecting the environment.
Materials and Methods: This research was conducted as a pot experiment at the department of Horticultural Science‚ college of Agricultural‚ Ferdowsi University of Mashhad‚ Iran, during 2012-2013.The research was set out in a factorial experiment on the basis of completely randomized block design with three replications.Two hydrophilic polymer Stockosorb® (industrial) and malva leaf (herbal) with two application methods (mixed with soil, mixed with soil+root) at 4concentrations (0, 0.1%, 0.2% and 0.3% w/w) were used. Leaf number, leaf area, dry matter yield, water use efficiency, essential oil quantity and yield were measured. Improved seeds of Ocimum basilicum var. Keshkeniluvelou were sown and seedlings were transplanted to the pots in four-leaf stage. Hydrogels were prepared and mixed with water after weighing the polymers according to determined concentration. After establishment, all pots were irrigated with a determined amount of water after reaching to the highest concentration (0.3%) of the wilting point. So, in this state in addition to the treatment at 0.3% treatment, lower levels (0.2% and 0.1%)were reached to wilting point earlierand were exposed to water stress.
Results and Discussion: Superabsorbent polymers can by absorption of irrigation and rain water, prevent deep percolation of water and with decreasing irrigation interval and reduced water consumption and increase water use efficiency. The results showed that using Stockosorb superabsorbent polymer and malva leaf as herbal hydrophilic polymersare useful for water supply of the plant in water stress.Application of these substances on morphological characteristics, water use efficiency and basil oil, were superior to the control.According to the obtained results, malva leaf use in soil and roots in treatmentless than (0.1% and 0.2%)number and leaf area and higher than (0.3%)increased dry matter yield, water use efficiency and the essential oil quantity and yield. Stockosorb (0.2%) byboth applying methods increased dry matter yield and water use efficiency. Also Stockosorb (0.2%),soil application increased leaf number and area. The essential oil yield and quantity increasedwith use of Stockosorb in soil + root in for0.2% and 0.3% treatments, respectively.
Conclusion: Due to the importance of cultivation of medicinal plants to provide conditions to increase essential oil yield and quantity at the same time, the best method used were malva leaf and Stockosorb with concentrations higher than (0.3%) and soil application methodor the use of both polymers with application method in soil + root in the moderate concentration (0.2%).For that purpose, we obtained favorable conditions for improving the morphological characteristics, water use efficiency and increasing the quantity and of essential oil yield in drought stress simultaneously. The results showed that natural compounds can be a good alternative for chemical compounds, but further experiments are needed for their commercialization.
