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.
Meysam Mansouri; Mahmood Shoor; Ali Tehranifar; Yahya Selahvarzi
Abstract
Gerbera is one of the ten important cut flowers in terms of production and consumption in the world and Iran. In this research effects of foliar application of salicylic acid and thiamine on biochemical characteristics of gerbera flower were investigated. This experiment was conducted in a completely ...
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Gerbera is one of the ten important cut flowers in terms of production and consumption in the world and Iran. In this research effects of foliar application of salicylic acid and thiamine on biochemical characteristics of gerbera flower were investigated. This experiment was conducted in a completely randomized design with four replications in the greenhouse commercial of the Golazin Maghsoud Company. Treatments were included of municipal water (control), salicylic acid 75 and 150 µM and thiamine 250 and 500 µM. Foliar application was performed with interval of two weeks in two stages. The results showed that the treatments had a significant effect on biochemical characteristics of gerbera. The greatest amount of chlorophyll a (36.6 µg/g Fw), b (17.27µg/g Fw) and total chlorophyll content (61.17 µg/g Fw) were related to Thiamine 250 µM and the highest level of carotenoids content 7.87 (µg/g Fw) was related to Thiamine 500 µM. The most reducing sugars content (181.51 mg/g Fw) reported in 75 µM salicylic acid. The highest activity of catalase and peroxidase enzyme (94.5 and 70.7 unit enzyme per minute in gram fresh weight, respectively) were related to 75 and 150 µM salicylic acid. Thus, salicylic acid and thiamine increased photosynthetic pigments, antioxidant enzyme activities.
