Medicinal Plants
F. Soleimani; D. Samsampour; A. Bagheri
Abstract
Introduction
Medicinal plants have reservoirs rich in the active ingredients of many medicines. Medicinal plants have rich reservoirs of essential active ingredients of many drugs. Considering the importance of medicinal plants, especially in the pharmaceutical industry and their scarcity in nature, ...
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Introduction
Medicinal plants have reservoirs rich in the active ingredients of many medicines. Medicinal plants have rich reservoirs of essential active ingredients of many drugs. Considering the importance of medicinal plants, especially in the pharmaceutical industry and their scarcity in nature, it is very important to study the various agricultural aspects of these plants, considering the increasing spread of saline soils, to find a solution. It seems necessary to prevent living and non-living environmental stresses or at least reduce them. One of these methods is the use of symbiotic relationships between mycorrhizal fungi and host plants, which reduces the stress caused by salinity. Due to the increasing expansion of saline soils, it seems necessary to find solutions that can prevent or at least reduce the living and non-living environmental stresses. There are different ways to overcome these tensions in different situations. Water salinization is one of the most important environmental limiting factors for crop production, especially in arid and semi-arid regions of the world, since Iran is located in the arid region of the world, given that salinity is one of the environmental factors. Are that have a strong effect on the growth and activity of lemongrass; There are also vast resources of saline and semi-saline groundwater, although not currently used and likely to be used in the future. Solutions to address abiotic stresses include the use of biofertilizers. One of these methods is to use the symbiosis of fungi with host plants, which leads to a reduction in salinity stress. The aim of this study was to investigate the effect of Arbuscular mycorrhizal fungi. On vegetative and biochemical traits of lemongrass under salinity stress. Salinity is one of the most important factors limiting the growth and production of crops. Fungi as a biological fertilizer can be useful in meeting the nutritional needs of plants and reducing the effects of environmental stresses on plants.
Materials and Methods
The experiment was a factorial experiment in a completely randomized design with two factors of four salinity levels (0, 5, 10 and 15 ds.m-1 NaCl) and fungi (no inoculation and fungal inoculation). For inoculation of Arbuscular mycorrhizal fungi with mixed potting soil was applied to the lemongrass. Plant height, root length, fresh and dry weight of leaves, relative water content, catalase, peroxidase and polyphenol oxidase were measured.
Results and Discussion
The results indicate that all studied traits were significantly affected by the interaction of mycorrhiza and salinity stress. The application of mycorrhizal fungi in the presence of salinity stress due to the absorption of nutrients and water led to improved growth of lemongrass. The results showed that under salinity stress of 150 mM plant height, root length, fresh and dry weight of leaves, relative water content, catalase, peroxidase and polyphenol oxidase enzymes in lemongrass inoculated with arbuscular fungus at 23.05, 32.69, 25.31, 48.14, 31.83, 30.33, 52.72 and 33.41% respectively, increased compared to the control (no inoculation). In general, based on the results of this study, it can be concluded that the use of mycorrhizal fungi can increase the salinity tolerance of lemongrass and cultivate it in saline soil.
Conclusion
In summary, the results of the present study showed that inoculation of the fungi can protect the lemongrass plant against salinity stress. In addition, the effect of mycorrhizal fungi on lemongrass under salinity stress has been investigated for the first time. According to the results obtained in this study, salinity reduced morphological parameters and lemongrass as a reaction to salinity to maintain its status to increase the amount of enzyme activity through the mechanism of osmotic regulation to stress conditions. Compromise and to some extent deal with salinity. In the study, it was observed that inoculation with Arbuscular had a positive effect on all measured traits. The application of mycorrhizal fungi in the presence of salinity stress due to the absorption of nutrients and water led to improved growth of lemongrass. By examining all the measured traits, it can be concluded that by using mycorrhizal fungi, the salinity resistance of lemongrass can be increased and cultivated in saline soil. Arbuscular species seems to be more suitable for improving the growth of lemongrass in all conditions.
F. Ghanbari; S. Akbari
Abstract
Introduction: Melon, like other members of cucurbitaceae family, is sensitive to cold stress. Applying different cultivation techniques in the nursery can provide some degree of tolerance to environmental stresses in the plants. In the other words, applying stress conditions on plants may cause them ...
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Introduction: Melon, like other members of cucurbitaceae family, is sensitive to cold stress. Applying different cultivation techniques in the nursery can provide some degree of tolerance to environmental stresses in the plants. In the other words, applying stress conditions on plants may cause them to withstand subsequent stresses, this is so called a cross-adaptation or cross-tolerance. For example, Whitaker (1994) showed that cold stress damage can be mitigated by temperature pretreatment. This technique was then used to improve stress tolerance in different plants. In this regard, heat treatment has been used to increase the chilling tolerance in fruits and vegetables. Therefore, in this study, the possibility of increasing cold stress tolerance in melon seedlings using heat shock was investigated. Materials and Methods: The experiment was conducted in a completely randomized design (CRD) with three replications and five treatments (including control and spraying with water at temperatures of 20, 45, 50 and 55 °C for 90 seconds) in Faculty of Agriculture of Ilam University in 2019. Heat treatments where used as foliar spray by heated water. After applying different levels of heat treatment and recovery at 24 hours, seedlings were exposed to chilling stress at 3 °C for 6 h in 6 consecutive days. All seedlings were transferred to greenhouse and after 72 hours, the related traits were measured. Results and Discussion: Results showed that pre-treated seedlings had higher growth rate than control seedlings at the end of chilling period. Heat shock pretreatment significantly increased the content of chlorophyll, proline and hydrogen peroxide and reduced the amount of malondialdehyde compared to the control. The lowest amount of malondialdehyde (1.14 nmol g-1 fresh weight) was observed in the 50 °C treatment, which was 50% lower than the control. Similar to other environmental stresses, low temperature usually leads ROS production and oxidative stress. Malondialdehyde content is an index to measure membrane lipid peroxidation and its measurement is a criterion of damage to plants in stress conditions. Reduction of malondialdehyde has been reported to increase cell membrane stability and increase stress tolerance in plants. In the present study, heat shock reduced the accumulation of malondialdehyde compared to the control, indicating a decrease in cold effects on the plant. Mei and Song (2010) investigated the effect of heat pretreatment on increasing high temperature tolerance in barley, and reported that using this method by stimulating the synthesis of antioxidant enzymes prevented the increase of malondialdehyde in the plant under heat stress. Therefore, maintaining the membrane structure and decreasing the accumulation of malondialdehyde in melon seedlings under cold conditions indicates an improvement of plant defense responses induced by heat shock. Environmental stresses including cold stress by producing hydrogen peroxide and other free radicals lead to oxidative stress and damage plant cells. Hydrogen peroxide is converted to water by ascorbate peroxidase, peroxide redoxin, glutathione peroxidase and guaiacol peroxidase groups. Therefore, increasing the activity of antioxidant enzymes in plants is one of the most important mechanisms of the plant to cope with stress conditions. In the present study, heat shock pretreatment significantly increased peroxidase (POD) and poly phenol oxidase (PPO) activity and increased the amount of proline and hydrogen peroxide. In this regard, it has been reported that hydrogen peroxide has a dual role in plants and its increase in stress conditions by regulating the production of antioxidant enzymes helps plants to enhance their tolerance to the stress conditions. Our results is in consistent with Ao et al. (2013) report that stated hardening pretreatment of Jatropha curcas seedlings caused to increase the antioxidant enzymes activity, plant glutathione and ascorbate content. The increases in antioxidant enzymes activity by heat shock might be a positive mechanism, which facilitate the scavenging of ROS and induce plant growth and development under chilling stress. These results indicate that antioxidant defense system has a specific role in enhancing plant tolerance to stress conditions and hydrogen peroxide play an important signaling role in plant adaptive responses. Conclusion: In general, the results showed that heat shock (especially at 50 and 55 oC) caused positive physiological changes in melon seedlings and could increase their tolerance to cold stress conditions.
A. Angooti; J, Hajilou; F. Razavi
Abstract
Introduction: The ability to tolerate cold will not be possible without stopping or inducing sleep, which is one of the important steps in the life cycle of plants in temperate regions. This period is one of the important factors in preventing cold damages in winter and spring in temperate regions. Various ...
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Introduction: The ability to tolerate cold will not be possible without stopping or inducing sleep, which is one of the important steps in the life cycle of plants in temperate regions. This period is one of the important factors in preventing cold damages in winter and spring in temperate regions. Various studies in controlled conditions on plants have shown that in plants, when entering and leaving this period, various changes occur in materials such as proteins, enzymes and hormones. In order to control the harmful effects of active oxygen species, plants have defense mechanisms. Catalase, peroxidase and superoxide dismutase enzymes are a defensive team whose common goal is to defend against the destructive effects of active oxygen species. This study was carried out to determine the chill requirement and its relationship with the changes in the activity of antioxidants enzymes and proline.
Materials and Methods: The experiment was conducted at agricultural Research Station of Khalat-Pooshan and the Laboratory of Flower Biology and Physiology of Fruit Growth in the Department of Horticulture, Faculty of Agriculture, Tabriz University in 2015-2016. Flower buds needed for testing were selected from ‘Siah Shabestar’, Zard Mashhad, Zoodras cultivars and a local genotype of sour cherry. Once a month, enough buds were harvested and until the experiments began, they were kept inside the freezer inside an aluminum foil at -80 ° C. In order to estimate the chill requirement, four replicates (4 geographic directions) from each cultivar and from each replication four branches with the same length and diameter were removed. The amount of chilling accumulation and chilling requirement in each month was calculated according to Utah model. In order to estimate fresh weight, four replicates in each cultivar were selected and in each replication five buds were selected from different parts of the branch. The statistical design used in the determination of the chill requirement was a randomized complete block design. Enzymatic and proline data were analyzed in a completely randomized design as factorial
Conclusions: Chill requirement: Based on the Utah model, the chill requirement of sweet and sour cherry cultivars contains Zard Mashhad, Zoodras and Siah Shabestar were calculated 752, 780, 867 and 961 CU, respectively. There was a significant difference in the activity of superoxide dismutase enzymes between cultivars and different sampling times at 1% probability level. Siah Shabestar cultivars with the highest chill requirement had the lowest SOD enzymatic activity and Zard Mashhad and Zoodras were intermediate cultivars in terms of enzymatic activity. Sour cherries, which had the least chill requirement, showed the highest levels of SOD enzyme activity. This is consistent with the results of some researchers regarding apricot stated that the low chill apricot cultivars had the highest SOD enzymatic activity. The sour cherry had the highest amount of POX enzymatic activity with the least amount of chill requirement, and also Siah Shabestar has the least chill requirement. Like the two previous enzymes, the activity of catalase was highest in sour cherries and the lowest was observed in Siah Shabestar. In terms of the presence of free proline, there was no significant difference between the Zard Mashhad cultivars and Zoodras, while there was a significant difference between these two cultivars and Sour Cherry and Siah Shabestar. Zoodras cultivar has the highest and our cherry has the lowest amount of free proline. Between different cultivars, in terms of fresh weight of buds, there is a significant difference at 1% probability level before and after placement in the growth chamber. The increase in fresh weight of sour cherry and Zard Mashhad, Zoodras and Siah Shabestar cultivars were 25, 27, 31.5 and 33%, respectively. The highest fresh weight before and after placement in growth chamber was observed in Siah Shabestar and sour cherry was the lowest. In all the cultivars, the activity of all three enzymes were initially at maximum (369 CU), then, with the cooling of the air and the initiation of deep dormancy, the activity of these enzymes were greatly reduced (820 CU) and then again increased in the activity of this enzyme (963 CU), which is similar to other studies.
Conclusions The results of this study showed that the antioxidant metabolism in plants is influenced by seasonal cycle changes and enzymatic activity changes depending on temperature, so that sour cherry with the least chill requirement has the most activity of the enzyme catalase, peroxidase and superoxide dismutase and Siah Shabestar, which have the most chill requirement, have the least enzymatic activity. Accordingly, the enzymatic antioxidant system activity of the flower buds was relatively high at the beginning of the dormancy period, but decreased during the end of dormancy. Also, the amount of free proline at the end of dormancy and the stage of dormancy breaking was highest and the lowest was in the deep dormancy period.
maryam haghighi; maryam mozafariyan
Abstract
Decreasing irrigation via partial root zoon drying (PRD) save water and decreased production expenses. For comparing common irrigation and PRD on tomato cv. Falcato an experiment was designed in Massey University of New Zealand. Treatments were control (irrigation in a Field capacity in each irrigation ...
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Decreasing irrigation via partial root zoon drying (PRD) save water and decreased production expenses. For comparing common irrigation and PRD on tomato cv. Falcato an experiment was designed in Massey University of New Zealand. Treatments were control (irrigation in a Field capacity in each irrigation to whole root zoon) and PRD (irrigation in a half of Field capacity in each irrigation to one side of root zoon). The results were shown that superoxide dismutase and peroxidase activity increased in PRD compare with control. Photosynthesis, mesophyll conductance, photosynthesis water efficiency, fresh and dry weight of root and shoot decreased in PRD. NACE (Nutrient Acquisition Efficiency) of leaf was the highest for Zn and Na and the lowest for P when PRD applied compare with control. Yield indices like MP increased significantly by 63% compare to first harvest. YSI (Yield Stability Index) increased by 46% in third harvest compare with second one. The TOL (Tolerance index) increased by 80% in last harvest compare with first one. GMP (Geometric Mean Productivity) in the second harvest increased by 62% compare to first one.
Z. Bearanvand; Naser Alemzadeh Ansari; M. Mosavi; A. Golpaigani
Abstract
In order to study, non-enzymatic antioxidants level of carotenoid and ascorbic acid in parsley leaves of twenty-one masses were compared between the first and second harvest. Also for evaluation of enzymatic-antioxidant activity, catalase and peroxidase activity in leaves of two twenty-one masses were ...
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In order to study, non-enzymatic antioxidants level of carotenoid and ascorbic acid in parsley leaves of twenty-one masses were compared between the first and second harvest. Also for evaluation of enzymatic-antioxidant activity, catalase and peroxidase activity in leaves of two twenty-one masses were measured at the end of vegetative growth. In each replication, one gram of fresh mixed leaf tissue of all samples was selected to measure the above mentioned parameters based on standard methods. , The data were analyzed in a randomized complete block design by SAS software. Results showed that the highest and lowest levels of carotenoids in the first harvest were7.54 and 2.00 mg/100 g in Bushehr 149 and Lorestan 69 masses, respectively. The maximum and minimum levels of vitamin C in the first harvest were 0.733 and 0.039 mg/100g in Lorestan 153 and western Azarbaijan 51 masses, respectively. The highest and lowest peroxidase activity were found 3.25 and 0.11 micromole of hydrogen peroxide per minute in central mass 46 and control region (native Ahwazi) respectively. The highest and lowest catalase activity were related 0.645 and 0.006 micromole of hydrogen peroxide per minute to Eastern Azerbaijan 62 and Central 45. According to results of this study, Lorestan 153, Lorestan 69, and Hamadan 49 masses could be introduced as the best masses of antioxidant activity.
