Medicinal Plants
M. Sohrabei; D. Samsampoor; A. Bagheri
Abstract
Introduction Medicinal plants have historically been one of the main sources of medicine and pharmacy in most parts of the world, that among these plants, we can mention the species Citrullus colocynthis L. Schrad. Cell suspension culture is a widely used method to increase the rate of secondary ...
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Introduction Medicinal plants have historically been one of the main sources of medicine and pharmacy in most parts of the world, that among these plants, we can mention the species Citrullus colocynthis L. Schrad. Cell suspension culture is a widely used method to increase the rate of secondary metabolites. The secondary metabolites of plants, are species compounds often produced during a certain period of growth and development and have important ecological functions in plants. They induce the ability of plants to cope with herbivores, microbial pathogens, adsorbents, and seed-spreading organisms. Also, due to the role of fungal elicitors to increase the rate of secondary metabolites in plants, in this study, we studied the role of the endophytes Alternaria solani. Fusarium sp. and Setosphaeria rostrata extracted from Citrullus colocynthis L. Schrad were collected from different regions of Hormozgan province as bio-elicitors in a cell suspension culture medium.Materials and Methods The study was performed based on a factorial experiment in a completely randomized design with two factors (the first factor had two levels of different hormonal composition and the second factor had eight levels of endophytic fungal extracts) with three replications in the biotechnology laboratory of Hormozgan University and the results were analyzed statistically using SAS 9.4 software. To produce the callus and culture of cell suspension under hormone treatment, watermelon seeds were first disinfected for a period of time and then the seeds were transferred to a culture medium containing MS and placed in a suitable incubator for seed germination. After germination and leaflet production, pieces with an area of approximately 1 mm2 were separated from the primary leaves and for callus formation were transferred to Petri dishes containing MS medium (3% sucrose, 0.8% agar), with two levels of 1mg 2,4-D + 1mg BA and 1mg 2,4-D + 1mg kin and placed in a suitable incubator for three weeks. Three fungal endophytes Alternaria solani, Setosphaeria rostrata, and Fusarium sp. were transferred separately to PDA (Potato Dextrose Agar) culture medium to prepare the bio elicitor and placed at 30 ° C for 7 days. From 7-day cultures, 1 cm2 of mycelium was isolated and inoculated into 150 ml of PDB (Potato Dextrose Broth) culture medium. The cultured cells were stored at 30 ° C in a 500 ml Erlenmeyer flask and placed on a shaker for 7 days at 120 rpm. The fungal cells were isolated and dried at 65 ° C for 24 hours. The powder from the dried cells was dissolved in water (10 g / l) and autoclaved for 20 minutes at 121 ° C. The extracts of these cells were finally used as a bio elicitorto study the change in the number of secondary metabolites. After that, the growth rate of cells in cell suspension culture was measured before and after the application of fungal extract. Parameters such as total phenol content, antioxidant activity, and flavonoids were also studied.Results and DiscussionThe results showed that the treatment combinations of 1mg 2,4-D + 1mg BA and inoculation of the plant with three fungi, the amount of phenol and flavonoids increased by 62.11% and 49.18%, respectively, compared to the control and at the levels of 1% and 5% probability were significant and was observed in the combination of hormonal treatment 1mg 2.4-D + 1mg Kin and inoculation of three fungi, the amount of antioxidant production increased by 62.78% compared to the control and at the levels of 1% probability was significant. The results indicated that the cell extraction of the fungal endophyte Alternaria solani, Fusarium sp., and Setosphaeria rostrata under condition hormonal treatment can be used as an effective stimulant in increasing the amount of secondary metabolites (phenol, flavonoids and antioxidant) of Citrullus colocynthis L. Schrad. Conclusion It was revealed that by adding the elicitor to the culture medium, cell growth was increased. The results showed that the combination of three types of endophytic fungi Alteynaria solani, Setosphaeria rostrata and Fusarium sp. led to a significant increase in cell dry weight compared with the control treatment. Also, an increase in cell growth was observed even when a fungal extract was used alone. The amount of metabolites in cells treated with fungal extracts (fungal elicitors) was significantly higher than metabolites produced in the control. According to the results of this experiment, using a combination of three fungal extracts was the best treatment to increase the metabolite production in the culture of cell suspension of Citrullus colocynthis L. Schrad.
Postharvest physiology
Soheila Aghaei Dargiri; Davood Samsampour; Majid Askari Seyahooei; Abdolnabi Bagheri
Abstract
Introduction: Tomato (Solanum lycopersicum L.) is a common vegetable that is widely cultivated and consumed worldwide in the Solanaceae family (global tomato production is estimated at approximately 182 million tons in 2017). Tomato, because of its elevated nutritional value, is the second most common ...
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Introduction: Tomato (Solanum lycopersicum L.) is a common vegetable that is widely cultivated and consumed worldwide in the Solanaceae family (global tomato production is estimated at approximately 182 million tons in 2017). Tomato, because of its elevated nutritional value, is the second most common vegetable commodity in the world after potatoes. As with other crops, the global production of tomatoes is threatened by certain biological stresses (such as pests, plant diseases and weeds) and non-biological stresses (such as salinity, drought, floods, cold and heat stress). Nowadays, the excessive use of chemical fertilizers in tomato production in order to increase yields, has resulted in environmental pollution and dangers on the health of consumers. The reaction of cultivated plants to these challenges is indicated by numerous morphological, physiological, biochemical and molecular changes, leading to a direct and indirect decrease in plant growth and productivity. Salinity as a non-biological stress can cause osmotic or ionic imbalance in plant cells. Salinity stress also limits growth and germination by affecting water and reducing water availability and affects crop production. Endophytes represent an eco-friendly option for the promotion of plant growth and for serving as sustainable resources of novel bioactive natural products. One of the alternative ways to restore normal plant growth under salinity stress may be to use plant growth to stimulate endophytes. Endophytes can play an important role in plant survival under salinity stress by reducing the adverse effects of sodium ion. Therefore, this work provides strong evidence that endophyte halophyte can be beneficial for tomato that help tolerate the plants stress. Materials and Methods: The main aim of this study was to investigate the role of endophytic bacteria (Exigubacterium aurantiacum), isolated from Salsola imbricate, in improving the growth of Solanum lycopersicum L. (8320) under salinity stress. The salinity tolerance potential of bacterial endophytes was investigated in vitro. The bacterial was cultured in Nutrient Agar with different concentrations of NaCl (1, 2 and 3 M) and its growth dynamics were investigated after 24 and 120 hours. To prepare the bacterial suspension for inoculation with tomato seeds, the bacteria were cultured on NB (Nutrient Broth) medium for 24 hours in an incubator at 28±1 °C at 130 rpm. The OD suspension was adjusted to a concentration of 1×108 ml. Tomato seeds (cultivar 8320) were washed with ethanol (70%) for 30 seconds and then sterilized with 0.5% sodium hypochlorite for 90 minutes and then completely distilled three times with distilled water. They were autoclaved and washed. For better contact of seeds with bacteria, 1% carboxymethylcellulose was used and then the seeds inoculated with bacterial treatments were placed on a shaker for six hours. Seeds inoculated with bacterial endophytes were planted in seedlings and then placed in pots containing autoclaved soil in the greenhouse of the Faculty of Agriculture, Hormoz University. The experiment was arranged in a factorial experiment based on randomized complete block design with three replications. Experimental treatments included five levels of salinity stress (0, 4, 6, 8 and 10 dS/m-1) and bacterial endophyte inoculation (E. aurantiacum). Analysis of variance of traits was performed using SAS software version 9.4 and the means were compared using LSD method with a probability level of p < /em> Results and Discussion: Analysis of variance showed that among treatments there is significant difference on growth parameters of tomato seedling (p < /em> 0.01), this indicate the positive impact of the bacterial endophyte on the growth parameters of tomato seedling is inoculated with the bacterial than the control plants. In this experiment, stem height, dry weight of stem, leaf and root, percentage of electrolyte leakage, chlorophyll a, chlorophyll b, carotenoid, proline and carbohydrate content were examined. The results of mean comparison showed that salinity stress significantly reduced stem height, stem dry weight, leaves and roots, chlorophyll a, chlorophyll b, carotenoids and increased electrolyte leakage; however, bacterial endophyte reduced the negative effects of salinity stress on tomatoes. Tomato seedling treated with endophytic bacteria showed higher levels of key osmolytes, total soluble carbohydrates and free proline compared to untreated plants under salinity stress. Conclusion: The results also showed that the use of endophytic bacteria increased the growth of tomatoes in saline soil and water, thereby it can be used as an effective tool for growing salinity-sensitive plants such as tomatoes in saline conditions.
