Medicinal Plants
Behrooz Rahimkhani; Mahboobeh Naseri; Ahmad Ahmadian; Masoud Alipanah
Abstract
Introduction:From the past, medicinal plants have been used as one of the most important resources for medicinal purposes. Even now, the use of medicinal plants is expanding in many developed. Salinity stress is one of the most important influencing factors in reducing plant growth. Salinity stress limits ...
Read More
Introduction:From the past, medicinal plants have been used as one of the most important resources for medicinal purposes. Even now, the use of medicinal plants is expanding in many developed. Salinity stress is one of the most important influencing factors in reducing plant growth. Salinity stress limits plant growth by reducing metabolic and physiological activities in the plant. One of the consequences of salinity stress in the plant is the production of abscisic acid in the plant. One of the methods that have been tested in recent years to reduce the effects of salinity stress in plants is the use of seaweed and its extract. According to the studies conducted in some plants, seaweed extract can cause the growth and expansion of the roots and help to increase the absorption of water and minerals through the roots. Also, based on the research conducted on some plants, the use of seaweed increases the amount of chlorophyll in the plant and accelerates the time of flowering and fruit formation in the plant. Echium amoenum is a perennial plant belonging to the family Borage is a valuable plant in terms of its medicinal properties is considered. in general environmental factors have a significant effect on flower production in these plants. Therefore, for the successful cultivation of medicinal plants, including in general environmental factors have a significant effect on flower production in these plants. Therefore, for the successful cultivation of medicinal plants, including Echium amoenum, providing optimal environmental conditions is a priority, providing optimal environmental conditions is a priority.Ascophyllum nodosum seaweed extract contains significant amounts of high-use mineral elements such as nitrogen, potassium, calcium, magnesium, and low-use mineral elements such as iron, copper, and manganese. Therefore, according to the current results, in this study, the effect of foliar spraying of algae extract was investigated. The morphological characteristics of Echium amoenum seedling under salt stress were investigatedMaterials and MethodsIn order to investigate the effects of foliar spraying of seaweed extract on borage flower seedlings under salinity stress conditions, a factorial experiment was conducted with two factors of seaweed and salinity stress with sodium chloride salt, in the form of a completely randomized design in the greenhouse. The seeds were purchased from Pakan Seed Company of Isfahan and soaked in normal water for 24 hours, and then they were transferred into small pots containing three parts of peat moss and one part of perlite. One week after transferring the seedlings to the main pots, foliar spraying with seaweed extract was done. Foliar-spraying was repeated once every two weeks and in total the seedlings were sprayed three times with seaweed extract. In this experiment, a concentration of 1500 ppm of seaweed extract and three levels of salinity (EC=1.6, 4, 8) were used.The seaweed extract used in this experiment belonged to Akadin Company. The type of seaweed from which the extract was prepared was Ascophyllum nodosum and it is a type of brown algae. One week after the first foliar application of seaweed extracts, the application of salinity stress began. In order to prevent shock in plants, salinity treatment was done gradually and in three stages. In order to prevent salt accumulation, washing with ordinary water was done once every two weeks. Results and DiscussionThe results showed that the use of seaweed extract can significantly protect plant growth under salinity stress. Seaweed extract increased the amount of proline and potassium in the leaves of the plant and thereby reduced the harmful effects of salinity stress on the borage plant. In addition, foliar spraying of borage plant with the use of seaweed extract increased the amount of chlorophyll in the plant, and in this way, by increasing the amount of photosynthesis in the plant; it helped the plant to grow better under salt stress conditions. The results of this research showed that the use of seaweed extract helps the plant to maintain its conditions against salt stress by increasing the amount of proline and absorbing potassium in the tissue. In addition, foliar spraying with seaweed extract preserves the structure of chlorophyll in the plant under salinity stress, and in this way, by increasing the photosynthetic efficiency, it helps the plant grow better under salt stress. According to the obtained results, it can be concluded that the use of seaweed can reduce the negative effects of salinity stress in the seedlings of Iranian borage. In addition, due to its low price and availability, it can be used as a suitable bio-fertilizer to protect plant growth under salinity stress conditions.
Amirhooshang Jalali; Peyman Jafari
Abstract
Introduction: Spinach is an important leafy vegetable in the cold season, and despite the fact that is considered as low-calorie food source contains significant amount of minerals such as iron, and vitamin A and C. According to the University of Utah 3.8 dS m-1 is salinity tolerance threshold for the ...
Read More
Introduction: Spinach is an important leafy vegetable in the cold season, and despite the fact that is considered as low-calorie food source contains significant amount of minerals such as iron, and vitamin A and C. According to the University of Utah 3.8 dS m-1 is salinity tolerance threshold for the spinach and yield decrease that have been reported by 10%, 25% and 50% at 5.5, 7 and 8 dS m-1 salinity. The necessity to supply adequate potassium has been demonstrated in salinity conditions. In salt stress conditions, foliar application of K in spinach, reduces the harmful effects of salt and increase the ratio of potassium to sodium (1.61 to 2.72). Foliar application of K with prevent of potassium transfer from root to shoot is causing continuation of photosynthesis and reduce the effects of salinity. Absorption of potassium from the leaves depends on the type of used compound. In this context, characteristics of plant (leaves with a waxy composition, duration of growth and leaf area) are important. 100 kg ha-1 of potassium in salt stress conditions by reducing the absorption of sodium, increased salt tolerance on the sunflower.
Materials and Methods: In order to evaluate the foliar application of K on the yield and yield components of spinach in salt stress condition, a study was conducted in 2012 by using split plot randomized based on complete block design with four replications at Isfahan Agricultural and Natural Resources Research Station. Three levels of irrigation water salinity consisted of a control (2 dS m-1), well water with salinity (4 dS m-1) and well water with salinity (8dS m-1) arranged in main plots and two levels of control and foliar applications of potassium fertilizer containing potassium oxide solubility in water (2.5 ml per liter) arranged in subplots. Statistical analysis was conducted by using SAS software and statistical tests were compared with Duncan at 5 percent.
Result and Discussions: The results showed that the yield of spinach with foliar application of K and 4 dS m-1 salinity was equaled 35300 kg ha-1 which had not significantly different from control treatment. Foliar application of K and 8 dS m-1 salinity, and also 8 dS m-1 salinity and without foliar potassium, had 20.2 and 38% yield reduction, respectively. In salinity 2.1, 4 and 8 dS m-1 plants m-2 were 40, 38.1 and 29.1, respectively. Leaf dry matter percent was improved with foliar application of K in 8 dS m-1 salinity. Effect of potassium, as modulators of salt in spinach, by researches of Shannon and Greve (24) and Kaya et al (14) have also been emphasized. Spinach leaves number was from 11.4 to 16.7 in different treatments. Foliar application of K in 4 and 8 dS m-1 salt treatment was increase in the number of leaves. This increased in treatment of 4 and 8 dS m-1 was 15.3 and 28.9 percent, respectively. In both saline treatments of 4 and 8 dS m-1, leaf length was positively affected by the application of potassium but in salinity 4 dS m-1 (unlike the eight salinity dS m-1) leaf width was not affected by the potassium spraying. The ability of plants to maintain intracellular potassium to sodium ratio leaves in certain extent is necessary for a salt tolerance. In fact, the application of potassium in salinity conditions by increasing the concentration of the K in organs is a kind of acclimation to the salt stress and activates repair mechanisms of the damage against of stress agent. The length of tail leaves in 4 dS m-1 salt was not significantly affected by the spraying of potassium while in 8 dS m-1 salinity, spraying potassium led to an increase of 28 percent in length of leaf tail. The effect of K application on the dry matter content in the 8 dS m-1 salinity was statistically significant. Potassium is the most abundant cation-forming in many plants (typically more than 10% of dry weight) and less than 10 grams per kg-1 of dry weight appear deficiency symptoms in most plants.
Conclusion: According to the results, in salinity conditions, the foliar application of K can be used as a factor to reduce the harmful effects of salinity. While the lack of fresh water for irrigation in arid and semi-arid crops has become a challenge, attention to the moderated mechanisms of the harmful effects of salt, is one of the approaches to face the challenges ahead.
