جستجوی مقالات مرتبط با کلیدواژه "catalase" در نشریات گروه "کشاورزی"

Water stress is one of the main factors in crop growth in arid and semi-arid regions of the world, which limits the grain yield of the safflower (Carthamus tinctorius L.). To increase the soil fertility and yield of crops, it is necessary to pay sufficient attention to the use of biomass of organic matter, especially crop residues, and its conversion to biochar. This research aims to evaluate the biochar application produced from cotton and wheat residues under late-season water stress in the south of Fars province (Darab) on photosynthetic pigments, enzyme activity, yield components, and yield of safflower.
In order to investigate the biochar application and water stress on the amount of photosynthetic pigments, enzyme activity, and yield of safflower, a field experiment was laid out as split plots in the form of randomized complete block design with 3 replications in the 2019-2020 growing season. The experimental factors include the irrigation regime as the main factor in two levels (optimal irrigation and cutting off irrigation after the flowering stage), and the secondary factors were fertilizer treatment as subplot including control (without fertilizer), consumption of 3 tons of biochar from wheat residues per hectare, consumption of 3 tons of biochar from cotton residues per hectare, consumption of 150 kg of urea per hectare + 50 kg of triple superphosphate per hectare, consumption of 112.5 kg of urea per hectare + 37.5 kg of triple superphosphate per hectare, consumption of 112.5 kg of urea + 37.5 kg of triple superphosphate + 3 tons wheat biomass per hectare, and 112.5 kg of urea + 37.5 kg of triple superphosphate + 3 tons of cotton biomass per hectare. In this research, chlorophyll a and b, total chlorophyll, catalase, and peroxidase activities, yield components, and yield of safflower were calculated.
The results of the experiment showed that the measured traits were significantly affected by the irrigation regime and fertilizer treatment. Under cutting-off irrigation after the flowering stage, the fertilizer treatment of 112.5 urea + 37.5 phosphate + 3 tons of wheat biochar per hectare increased 55 and 40% chlorophyll a and total chlorophyll compared to the control, respectively. Water stress increased the carotenoid content, catalase, and peroxidase enzymes. The highest amount of catalase and peroxidase enzyme activity was obtained in the control under cutting-off irrigation after the flowering stage, which increased by 48 and 38%, respectively, compared to the control under optimal irrigation. The number of seeds per capitule and the number of fertile capitules per plant in the treatment of 112.5 urea + 37.5 phosphate + 3 tons of cotton biochar under water stress conditions increased by 8.8 and 19.51%, respectively. Also, under water stress, the application of 112.5 urea + 37.5 phosphates + 3 tons of cotton biochar improved and increased the relative content of leaf water, biological capitules yield, and grain yield compared to the control by %53, %22, and %34, compared to control, respectively.
Results showed that in both of the irrigation regimes, application of 3 tons of cotton or wheat biochar alone can increase the biomass and grain yield compared to control. Overall, the application of 112.5 urea + 37.5 phosphate + 3 tons of cotton biochar under water stress conditions improved the relative water content of the leaves, the number of seeds per capitule, the number of fertile capitule per plant, and finally, biomass and yield of safflower. With respect to water shortage under late season in southern parts of Fars province, and in order to decrease the detrimental effects of water stress, farmers can use the biochar of cotton combined with reduced dosage of urea and triple superphosphate fertilizers.

In this study, changes in biochemical traits and yield of different autumn-sown sugar beet cultivars treated with gamma ray irradiation under salinity stress condition were evaluated in Jafariyeh region located in Qom province in two crop seasons of 2018 and 2019. The experiment was conducted as a split factorial based on randomized complete block design with three replications. The main plot includes irrigation at two levels (normal water and saline water with electrical conductivity of 7000 to 10000 µmos cm-1) and sub-plots were combination of sugar beet cultivars (Sharif, Antek, and Eudoro) and gamma radiation (0, 50, 100, 200 and 400 Gy). Results showed that the activity of rubisco enzyme decreased in all three cultivars under salinity stress, however the highest level of rubisco activity under both normal and salinity stress conditions observed in Eudoro cultivar at 50 and 100 Gy levels. The concentration of malondialdehyde in Eudoro and Antek cultivars decreased by gamma radiation while increased in Sharif cultivar. In all three cultivars, the highest amount of chlorophyll content at 100 and 200 Gy gamma ray radiation levels was associated with an increase of 15-16% compared with control. Under salinity condition at 100 and 200 Gy levels, the highest average root yield was observed. Salinity stress caused a decrease in sugar yield in Eudoro, Antek and Sharif by 26.7%, 17.5% and 31.5%, respectively. Antek cultivar had a lower sugar yield than the other two cultivars. In general, Antek cultivar showed a higher yield and tolerance to salinity compared with other cultivars, and gamma ray irradiation had a positive effect on this tolerance

Salinity affects about 1.7 million hectares of agricultural land in Iran, which poses a serious challenge for wheat production, as the most strategic crop in the country. Therefore, identifying wheat genotypes with salinity tolerance and selecting effective traits for accelerating the breeding process are crucial objectives.

The experiment was aimed at assessing the response of 12 wheat cultivars to different levels of salinity using NaCl concentration as salt stress at early seedling stage under hydroponic conditions. A factorial experiment based on randomized complete block design with three replications was conducted at the research greenhouse of the Agriculture Faculty, University of Zabul, during the 2020 cropping seasons. 12 wheat cultivars (Shiraz, Falat, Durum, Gascogne, Mahdavi, Alvand, Cross Azadi, Roshan, Star, Tous, Hirmand and Cross Bolani) were irrigated with four concentrations of NaCl (0, 100, 200 and mM). The physiological and biochemical traits of wheat cultivars, including seedling fresh mass, ascorbate peroxidase, glutathione peroxidase, catalase, proline, sodium, potassium, and potassium to sodium ratio (K+/Na+) were recorded at four weeks after seed germination.

The results showed that the amount of ascorbate peroxidase, glutathione peroxidase, catalase, proline and sodium in the leaves of wheat seedlings were increased with an increase in salinity level. In contrast, the seedling fresh mass, potassium content and K+/Na+ were decreased with an increase in salinity level. The increase of ascorbate peroxidase, glutathione peroxidase, and catalase activities, representing the main enzymatic H2O2 scavenging mechanism in wheat cultivars. In NaCl treated seedlings, Falat, Mahdavi and Cross Bolani cultivars showed higher ascorbate peroxidase than other cultivars tested. In contrast, high level of catalase was recorded in Alvand cultivar. In the other hand, maintain the high level of proline and potassium to sodium ratio are the main mechanisms for tolerance to salinity in Shiraz and Roshan cultivars, respectively. Wheat cultivars showed different response to the increase in salinity level, while in Roshan, Mahdavi, Hirmand and Cross-Bolani cultivars, the increase in salinity level had less effect on the seedling fresh mass than other cultivars, but different patterns of changes in physiological and biochemical traits were observed in these cultivars. Salinity resistance in Mahdavi cultivar was directly related to the increase of ascorbate peroxidase and catalase, but on the other hand, in Roshan cultivar, salinity resistance was related to maintaining a high level of potassium to sodium ratio. Potassium uptake is vital for plant growth but in saline soils because of their shared transport system and physicochemical similarities, the sodium in the soil solution competes for uptake with potassium and can lead to potassium deficiency. The induced potassium deficiency inhibits growth because it plays a critical role in maintaining cell turgor, membrane potentials, and enzyme activities. In salt-tolerant cultivars of wheat such as Roshan, under salt-stress conditions, limiting sodium uptake and preventing potassium losses from the cell may help to maintain a potassium to sodium ratio in the cytoplasm that is ideal for plant metabolism. Accumulation of high amounts of proline is often related with the salt tolerance nature of crop cultivar and high proline accumulation in the salt–tolerant cultivar than in their salt–sensitive are reported previously. The regression coefficients indicated that seedling fresh weight (R2=0.89), potassium (R2=0.86) and the ratio of potassium to sodium (R2=0.69) were the most reliable predictors of the effects of increasing sodium chloride concentration. These variables accounted for a large proportion of the variance in the response variable and had significant p-values.

According to the results of this experiment, it can be concluded that seedling fresh weight, potassium, and the ratio of potassium to sodium are more suitable criteria for selecting among cultivars under salt stress conditions.

Marigold (Calendula officinalis L.) is an annual plant in the Asteraceae family that has been cultivated for ornamental purposes for many years. However, the plant's medicinal properties have also been identified and it is now commonly used for medicinal purposes. The most abundant compounds found in marigold are phenolic compounds, including flavonoids and phenolic acids, as well as saponins. The biosynthesis of secondary metabolites in plants is heavily influenced by environmental factors, which are known to significantly affect both the quantity and composition of these compounds. Environmental factors can be present in varying conditions, sometimes in levels that are optimal for plant growth and sometimes in levels that are stressful and can negatively impact plant growth and development. A substantial portion of the earth's arable land, approximately 6%, is affected by salinity, which can lead to oxidative stress in plants. Although, zinc is an essential micronutrient required for plant growth, excessive levels of this element can be toxic and result in oxidative stress, ultimately leading to plant death. There are various methods to mitigate the impacts of metal toxicity and salinity stress on plants, and one effective approach is the use of biochar as a soil amendment. Beeswax waste has recently been identified as an organic material, and studies have shown that it is a nutrient-rich substance that can be applied as a fertilizer. Given the dual importance of marigold as both a medicinal and ornamental plant, the present study aimed to explore the potential of beeswax waste biochar in mitigating the negative impact of salinity and zinc stress on this plant species. Furthermore, the study aimed to investigate the effects of varying concentrations of zinc, ranging from low to high levels, on the growth and development of marigold. The study also examined the synergistic effects of zinc and salinity on marigold growth, as well as the role of both high and low concentrations of zinc under saline conditions and in the presence of different biochar levels.

To investigate the impact of beeswax waste biochar application on marigold growth under salinity and zinc stress, a factorial experiment was conducted using a completely randomized design with three replications. The experimental factors included two levels of salinity stress (control EC=1 dsm -1; salt stress with EC=6 dsm-1), four levels of zinc element (control, 300, 1500, and 3000 mgkg-1 soil), and three levels of beeswax waste biochar (control, 1.5%, and 3% ww-1). Biochemical traits, including photosynthetic pigments (chlorophyll a, b, and total), phenol, flavonoid, anthocyanin, catalase, and ascorbate peroxidase enzymes, were measured three months after planting. Yield traits, such as biomass and flower dry weight, were measured approximately four months after planting, when the plants exhibited signs of decline.

The results of the experiment revealed that salinity and zinc stress significantly reduced the biomass, flower and root dry weight, and height of marigold plants compared to the non-stress condition. Among the treatments, the highest amount of biomass and dry weight of flowers were observed in the control treatment (without salinity stress) with 300 ppm of zinc and 1.5% biochar, which were 9.83 gr and 1.59 gr, respectively. Conversely, the lowest values were observed in the treatment with 6 dSm-1 salinity and 1500 ppm of zinc concentration without biochar, which were 1.8 gr and 0.27 gr, respectively. Although the amount of photosynthetic pigments and secondary metabolites, such as phenolic compounds, flavonoids, and anthocyanins, decreased compared to the non-stress condition, the activity of catalase and ascorbate peroxidase enzymes increased under salinity and zinc stress compared to the control treatment. Furthermore, the application of biochar in plants under salinity and zinc stress conditions increased vegetative traits, improved photosynthetic pigments, secondary metabolites, and antioxidant enzymes compared to the condition of not applying biochar.

Low zinc concentration had a positive impact on marigold growth, but concentrations higher than 300 ppm resulted in toxicity and stress. Salinity and zinc stress caused a decrease in growth characteristics, photosynthetic pigments, and secondary metabolites. Remarkably, the application of biochar, even in the presence of salt stress with 300 ppm zinc concentration, improved the growth and biochemical characteristics of marigolds.

In order to investigate the effect of pretreatment of safflower seeds of Omid with salicylic acid on seedling growth, germination percentage and speed, seedling length and dry weight, proline content and change in catalase enzyme activity under drought stress conditions, experimentally in factorial form in a completely randomized design with three The replication was carried out in the laboratory of Seed Technology Science of the Faculty of Agricultural Technology of Aburihan in 1402. The test treatments included salicylic acid at four levels (zero, 0.5, 1 and 2 mM) and drought stress at four levels (no stress, -2 bar, -4 and -6 bar). Parameters such as germination percentage and speed, seedling length and dry weight, proline and catalase enzyme activity were measured. The results showed that the effect of salicylic acid and drought stress on germination percentage and speed, seedling length and dry weight, proline content and catalase enzyme activity were significant. Drought stress up to negative level 4 times increased the percentage and speed of germination, length and dry weight, seedling and proline content and catalase enzyme activity. Salicylic acid hormone at a concentration of one mM had an effect on increasing the measured parameters. The results showed that the best concentration of salicylic acid to deal with the effects of drought stress was one mM concentration in the conditions of low levels of drought stress. Therefore, with increasing levels of drought stress, treating seeds with salicylic acid hormone was not effective.

Pink evening primrose is one of the world's most well-known and economically valuable medicinal plant species. It has also been cultivated as an ornamental and medicinal plant in Iran. In addition, its seed oil is used in the pharmaceutical, food, cosmetic, and healthcare industries. Micronutrients and biofertilizers can enhance the quality of agricultural products. Therefore, this study was conducted to investigate the effect of arbuscular mycorrhizal fungi and zinc foliar spraying on the nutrient uptake morphophysiological and biochemical characteristics of pink evening primrose. This research was conducted on evening primrose for one year, from October 2022 to September 2023. For this purpose, evening primrose seeds were first grown for 120 days in greenhouse conditions in size 10 pots and then at the time of transplanting to the main pot, they were inoculated with Glomus intraradices arbuscular mycorrhizal species, and inoculation was carried out at two levels of inoculation and non-inoculation during the transfer of the seedlings of the main pot. This experiment was carried out factorially in a completely randomized design and foliar application of zinc element in zinc sulfate at three levels of zero (control), 3 and 5 mg/L in three replications at the eight-leaf stage. Before planting the plant, samples were taken from the soil mixture used, and the physicochemical test of the soil included The concentration of nitrogen, potassium, phosphorus and biomass carbon elements. The examined traits include Morphological traits (wet and dry weight of shoot, number of flowers per stem, flower diameter, length of flowering period, number of leaves, number of capsules, number of seeds in capsule, number of lateral branches) and number of mycorrhizal spores in the soil and physiological traits including chlorophylls a, b and total, carotenoid, phenol and flavonoid and antioxidant and activity of catalase and peroxidase enzymes were evaluated in leaves. The results showed that in the foliar treatment with 5 mg/l zinc sulfate, the number of flowers per plant, number of capsules per plant, number of seeds per plant, seed yield, number of internodes, number of secondary stems, fresh and dry weight of shoot and flavonoid phytochemical traits, antioxidant, catalase and peroxidase and in addition elements of phosphorus, zinc, boron, manganese, iron and copper were significantly different at the 1% probability level. Carotenoid, nitrogen and potassium elements were found to have a significant difference at the 5% probability level. The effect of inoculation treatment with arbuscular mycorrhizal fungus on the traits of number of flowers per plant, number of capsules per plant, number of seeds per plant, seed yield, flower diameter, stem diameter, leaf area, number of leaves, fresh and dry weight of shoot, plant height and length flowering period and in addition, total chlorophyll, phenol, flavonoid, antioxidant and catalase and elements of nitrogen, zinc, boron, manganese, iron and copper were significantly different at the 1% probability level. The traits of the number of secondary stems, carotenoids, and peroxidase were significant at the 5% probability level. The interaction effect of foliar spraying treatments with zinc sulfate 5 mg/litre and arbuscular mycorrhizal fungus on shoot weight and total chlorophyll at the 1% probability level, and the number of flowers, chlorophyll a, catalase and zinc element was observed to be significant difference at 5% probability level. The comparison between the treatments showed that the foliar treatment with zinc sulfate 5 mg/litre, along with the inoculation of arbuscular mycorrhizal fungus, had the most significant effect on increasing the amount of flowering, seed yield and phenolic compounds and catalase and peroxidase enzymes. In general, it can be concluded that among the treatments used, foliar spraying treatment with zinc sulfate (5 mg/litre) along with arbuscular mycorrhizal fungus can achieve high flower and seed yield by affecting the availability of nutrients and increasing vegetative growth. It can also increase the amount of chlorophyll and total carotenoid, flavonoid, antioxidant, catalase, and peroxidase of this valuable plant.

Drought stress, as one of the main abiotic stresses, affects plant growth and performance by affecting various physiological and biochemical processes, such as membrane integrity, photosynthetic pigments, osmotic adjustments, water relations, and secondary metabolism. Drought stress in plants causes oxidative stress due to the production of reactive oxygen species (ROS) during photosynthesis and respiration. ROS directly damage proteins, fats, nucleic acids and cell membrane, and due to the increase in membrane permeability, the rate of electrolyte leakeage and malondialdehyde increases. Plants mainly reduce the damage of these oxides by controlling the antioxidant system and regulating the content of osmosis compounds. Enzymatic antioxidant system: It includes antioxidant enzymes such as catalase, superoxidase dismutase, peroxidase and non-enzymatic antioxidant system including compounds such as ascorbate, glutathione, as well as phenol and flavonoids. Savory (Satureja hortensis L.) is one of the most important medicinal plants that grows in different parts of the world, including Iran. Biofertilizers play a prominent role in the growth and development of plants by improving the absorption of nutrients and sufficient water through changes in the physicochemical properties of the soil. The purpose of this study is to investigate the effect of drought stress, plant growth-promoting bacteria (PGPRS) and vermicompost on the physiological and biochemiclal traits of savory plant. In drought stress conditions, the application of organic fertilizers prevents the soil from drying out by maintaining moisture.   

In order to investigate the effect of inoculation with  Pseudomonas P15 bacteria, Streptomyces and vermicompost on some physiological and phytochemical traits of savory plant (S. hortensis L.) under drought stress conditions, a factorial experimental based on a randomized complete block design with three replications was conducted at the Research Farm at the Mohaghegh Ardabili University, Iran, during 2016-2017.The experimental factors include inoculation with microorganisms at three levels (control (without inoculation), inoculation with Pseudomonas P15 and Streptomyces bacteria),    vermicompost at four levels (0, 1, 1.5 and 2 tons). per hectare) and drought stress in three levels (S1: full irrigation, S2: water cut at 50% of flowering and S3: water cut at the beginning of flowering). 

The results showed that drought stress, inoculation with   microorganisms and vermicompost had a significant effect on the measured traits (chlorophyll, carotenoid, RWC, protein, electrolyte leakeage, proline, and antioxidant enzymes. Under drought stress conditions, the amount of chlorophyll, carotenoid, RWC and protein decreased. While the amount of electrolyte leakeage, proline, and antioxidant enzymes increased. Also, the values of all the measured traits, except the amount of electrolyte leakeage and proline, in plants inoculated with bacteria and vermicompost application were more than non-inoculated plants. The highest and lowest values of the RWC (94.44 and 62.33 percent) were obserwed in plants inoculated with Streptomyces bacteria under non-stress conditions and in non-inoculated plants under drought stress at the beginning of flowering respectively. Also, the highest amount of chlorophyll a, b and total (25.36, 20.25 and 45.61 mg/g FW) was obtained in non-stress conditions, application of two tons per hectare of vermicompost and inoculation with Streptomyces bacteria. While the lowest amount of chlorophyll a, b and total (16.73, 9.63 and 23.69 mg/g FW) was obtained in non- inoculation plants and without application of vermicompost under drought stress at the beginning of flowering. It seems under drought stress conditions, the application of organic fertilizers prevents soil drying by maintaining moisture, thereby improving the relative water content of the leaves. Also, the use of organic fertilizers such as vermicompost improves the absorption of nitrogen that leading to greater synthesis of photosynthetic pigments such as chlorophyll and carotenoids.

The findings of this research showed that inoculation with growth-stimulating microorganisms and the use of vermicompost can moderate the adverse effects of water stress on the growth and performance of savory plants by maintaining chlorophyll levels and increasing antioxidant activity. According to the results of this study, it can be stated that the application of Streptomyces bacteria and 2 tons per hectare of vermicompost in the field leads to sustainable production and yield of S. hortensis under drought stress conditions by improving physiological traits.

In order to investigate the effect of mycorrhizal fungi on some physiological traits and antioxidant enzymes the tarragon plant under drought stress, this study was performed as a factorial experiment with two factors based on a completely randomized design with three repetitions. The first factor was drought stress at two levels including 100 and 50% field capacity (pot capacity) and the second factor was inoculation with mycorrhiza fungus from Glomus geus at 5 levels consisting of (G.hoi + G. mosseae, G. hoi + G. intraradices, G. mosseae + G. intraradices, G. hoi + G. mosseae + G. intraradices and no inoculation as control(. According to the results, the use of mycorrhizal fungi under drought stress conditions increased the activity of the enzymes of the ascorbate peroxidase, hydrogen peroxide, guaiacol peroxidase, catalase, superoxide dismutase as well as the amounts of malondialdehyde, total phenol and ascorbic acid in the leaves. The use of mycorrhiza fungus, unlike drought stress, increased potassium and phosphorus concentration. Application of the three mycorrhizal fungi combination (G. intraradices +G.hoi + G. mosseae) had a better effect on the physiological and biochemical traits than the control. The results of the research showed the positive effect of mycorrhizal fungus in increasing drought tolerance of tarragon plant and better control of free radicals produced under stress conditions.

Drought stress is one of the most common limiting factors for crop production. Due to its detrimental effects on numerous physiological and biochemical processes, this stress restricts the growth and development of plants. In this regard, the application of stress modulators (methanol, silicon and humic acid) has been found to enhance plant growth and grain yield while also increasing its resistance to abiotic stresses. On the other hand, stress modulators can lessen the effects of stress toxic by reducing malondialdehyde and hydrogen ‎peroxide accumulation and keeping the effectiveness of the photosynthetic apparatus‎. Therefore, measurement of traits of such as antioxidant enzymes activity, chlorophyll content, proline and soluble sugars content, malondialdehyde content, electrical conductivity are as indicators of plant response to environmental stress. Although, several strategies have been developed to decrease the effects caused by drought stress on plant growth. But, among them, the application of stress modulators (methanol, nano silicon, and humic acid) plays a very important role in yield improvement. The aim of this study was to evaluate the effects of foliar application of stress modulators (methanol, nano silicon and humic acid) on the activity of antioxidant enzymes, compatible osmolytes, photosynthetic pigments content and grain yield of wheat in different irrigation regimes.

an experiment as factorial was conducted based on randomized complete block design with three replications in Agricultural and Natural Resources Research Station of Ardabil, Ardabil, Iran, in 2022-2023 growth season. The treatments were different irrigation regimes (normal irrigation as control; irrigation withholding at 50% of booting and heading stages) and foliar spraying of stress modulators (foliar spraying with water, foliar spraying of methanol (25% volume), nano silicon (50 mg.L-1), humic acid (300 mg.L-1), foliar spraying of methanol and silicon, methanol and humic acid, nano silicon and humic, methanol with nano silicon and humic acid). In each plot, there were six rows with two m long. In this experiment, the wheat cultivar ‘Hiran’ was employed. For this cultivar, 400 seeds.m-2 is the optimum density. The used nano silicon had an average particle size of less than 30 nm and the special surface of particles was more than 30 m2.g-1. They were product of Nanomaterial US Research which was provided by Pishgaman Nanomaterials Company of Iran. For a better solution, deionized water was mixed with nano Si powder and placed on a shaker with ultrasonic equipment (100 W and 40 kHz). Two phases of period growth, BBCH 21 and 30 were used for the foliar application of nano silicon.  In this study, the activity of antioxidant enzymes (Catalase, peroxidase, and Polyphenol oxidase), compatible osmolytes (Proline and soluble sugars), photosynthetic pigments content (Chlorophyll a, Chlorophyll b, total chlorophyll, and carotenoid), H2O2, MDA, protein content and grain yield of wheat were investigated.

The result indicated that both application stress modulators (methanol, silicon and humic acid) at irrigation withholding in booting stage decreased malondialdehyde content (39.79%) and electrical conductivity (31.25%), but increased activity of peroxidase (4.89%), polyphenol oxidase (7.73%) enzymes, soluble sugars (22.15%), chlorophyll a (33.48%), chlorophyll b (24.96%), leaf protein content (25.09%) and grain yield (36.21%) in compared to the no application of stress modulators under irrigation withholding in booting stage.

According to our findings, applying stress modulators (methanol, silicon and humic acid) under water limitation often reduced this damage by strengthening the defensive mechanisms, particularly antioxidant enzymes and compatible osmolytes (Proline and soluble sugars). In summary, our results indicated that application of stress modulators upgrade plant physiology and trigger the cellular defense of wheat plants against severe water limitation. Therefore, in can be suggested that applying stress modulators as individual and integrated could enhance grain yield of wheat under water limitation conditions due to improving of physiological and biochemical characteristics.

In order to study the effect of deficit irrigation on RWC, proline concentration, antioxidant enzymes content, chlorophyll concentration and forage yield of five clover species, a field experiment was conducted during the cropping season 2019-2020.  The experimental design was split plots arranged based on randomized complete blocks design (RCBD) with three replications. Deficit irrigation  at three levels (0 (Full irrigation), 20 and 40% less than the irrigation requirement) were considered as main plots and  five clover species (Trifolium resupinatum ، T. alexandrium ، T. lapaceaum ، T. echinatum و T. diffusum) were allocated as sub plots.The results showed by increasing deficit irrigation up to 40%, proline concentration increased by 93% and the content of antioxidant enzymes catalase, peroxidase and superoxide dismutase increased by 12, 98 and 83% respectively. However, RWC, yield of fresh and dry fodder decreased by 22, 24 and 29% respectively. The highest RWC, chlorophyll concentration and content of antioxidant enzymes were observed without significant difference in T. resupinatum and T. alexandrium species. The interaction effect of two factors (deficit irrigation × species) showed by increasing deficit irrigation, fresh and dry forage yield of all five species decreased significantly. In all three levels of deficit irrigation, the highest yield of fresh (20.39, 18.81 and 13.94 t/h) and dry forage (4.59, 4.25 and 3.06 t/h) were obtained in T. resupinatum species. In general, the results showed that all 5 species do not have the required stability under stress conditions. Therefore, deficit irrigation for the proposed species will be justified only if a 20 and 40 percent irrigation water reduction is more beneficial than the yield reduction.

Studying the effects of Azospirillum and nanoparticles (silicon and zinc) on grain yield and some traits of Triticale under salinity stress was conducted as a factorial experiment with randomized complete block design and three replications at the research greenhouse of the University of Mohaghegh Ardabili in 2022.

The experimental factors included salinity levels (no salinity as control, salinity of 60 and 120 mM by NaCl), application of Azospirillum (no inoculation as control and seed inoculation with Azospirillum), nanoparticles foliar application (foliar application with water as control, foliar spraying 0.8 g.L-1 nano zinc oxide, 50 mg.L-1 nano silicon, combined foliar application of nano zinc oxide as 0.4 g.L-1 and nano silicon as 25 g.L-1).

The application of Azospirillum and nanoparticles in 120mM salinity increased proline content (37.46 percent), hydrogen peroxide (41.66 percent), malondialdehyde (37.57 percent) and the activity of peroxidase and polyphenol oxidase enzymes (53.86 and 47 percent, respectively) compared with non-saline conditions and lack of Azospirillum and nanoparticles application. Application of Azospirillum and nanoparticles increased the content of soluble sugar (18.68 percent) and catalase enzyme activity (28 percent) as compared with treatments that did not receive Azospirillum application and foliar spraying. Not applying Azospirillum and nanoparticles under 120 mM salinity increased dry matter remobilization from aerial organs (54.25 percent) and the contribution of dry matter remobilization from aerial organs (126.14 percent) compared with the application of Azospirillum and nanoparticles under non-saline conditions.

It seems that applying Azospirillum and nanoparticle foliar application can increase grain yield of triticale under salinity stress due to improved biochemical traits.

Chemical compounds in plants include primary or secondary compounds. The allelopathic compounds are mainly of the secondary type, which are released by ways such as leaching, decomposition of plant residues, volatilization, and root exudation. Plants with allelopathic properties have a negative or even positive effect on the germination and growth of other plants by releasing substances in their surroundings. These effects depend on the type of organ, concentration, plant growth location, physiological maturity, etc.

An experiment was conducted to evaluate the allelopathic potential of wild barley (Hordeum spontaneum) weed on some germination, morphophysiological, and biochemical characteristics of a reference plant sensitive to allelochemicals, cress (Lepidium sativum), in 2021. This experiment was conducted in the form of a completely randomized design with three replications. The treatments included different concentrations of H. spontaneum aqueous extract at 11 levels (0, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100%).

The results showed that different concentrations of H. spontaneum aqueous extract had a significant decreasing effect on the percentage and rate of seed germination, radicle and shoot length, seedling length vigor index, radicle and shoot dry weight, as well as photosynthetic pigments (i.e., chlorophyll a, b, total, and carotenoids) of cress. Their effectiveness was dependent on the concentration threshold of the aqueous extract. In contrast, the content of proline amino acid , soluble sugars, ion leakage, catalase activity, guaiacol peroxidase enzymes, the concentration of malondialdehyde, and phenolic compounds showed an increasing trend compared with the control. In most cases, the highest increase in these compounds was obtained at the 100% aqueous extract concentration of H. spontaneum. This indicates the oxidative stress and high cytotoxicity caused by harmful compounds present in the aqueous extract of H. spontaneum.

According to the results of this experiment, it can be decucted that the aqueous extract of H. spontaneum, due to its allelopathic properties, prevented germination and seedling growth of L. sativum. Therefore, according to the proof of the harmful effect of H. spontaneum and its high biomass, it may be possible to introduce the bioactive compounds present in this plant for the production of environmentally friendly herbicides or even the potential to produce new formulations of synthetic herbicides in case its positive effect on other species is proven.

A large part of Iran is affected by arid and semi-arid climate and drought has caused many problems in the agricultural sector. The present study aimed to investigate the characteristics of melon under drought stress conditions using animal manure and bentonite. This experiment was conducted as a split-factorial based on a randomized complete block design with three replications in Hirmand city, Iran, during the two cropping years of 2019-2020. Experimental treatments include irrigation after 25, 50, and 75% soil moisture discharge as the main plot and application of bentonite at levels of 2, 3, and 4 t.ha-1 and application of animal manure at the rate of 20, 30, and 40 ton.ha-1 were considered as subplots. According to the results, in the first year of the experiment, fruit yield increased by 2.02 times compared to the control under 50% soil moisture discharge with the application of 4 t.ha-1 of bentonite with 20 ton.ha-1 of animal manure. The results showed that the fruit yield in irrigation conditions after draining 50% of soil moisture with the application of 4 t.ha-1 of bentonite along with 20 ton.ha-1 of animal manure in the first year of the experiment with an average of 2.20 ton.ha-1 and 74.1% compared to the control showed an increase. In order to achieve higher fruit yield, irrigation after draining 50% of soil moisture, application of 4 t.ha-1 of bentonite and 20 ton.ha-1 of animal manure are suggested for cultivation in Hirmand region. In this experiment, the greater effectiveness of fruit weight and yield in the first year can be attributed to the faster growth of shoots and the availability of more nutrients due to the release of manure elements for plant use and the effect of soil interactions in the first year, and the improvement of physical conditions and Soil and plant chemistry in the second year under irrigation conditions after draining 50% of soil moisture. The reason for the higher fruit yield due to the consumption of animal manure can be the result of the vegetative growth caused by the increase in the availability of nutrients, which causes photosynthesis and the production of more photosynthetic substances, followed by the presence of more vascular elements to transfer the cultivated substances to the fruit of the plant. Based on the obtained results, the increase in drought stress increased the activity of catalase and peroxidase enzymes, and the animal manure increased the activity of enzymes to defend the plant under drought stress conditions, in other words, the plant decomposes hydrogen peroxide and increases tolerance against radicals. The effect of animal manure on plant growth can be largely attributed to mineral nutrients, especially absorbed nitrogen. In addition to this, increasing the decomposition of organic materials and mineralization of phosphorus in organic materials and converting them into usable form for plants plays a key role in the soil phosphorus cycle, and along with the use of bentonite, it strengthens the physical, chemical and biological structure of the soil, and finally By increasing the amount of water and the availability of nutrients available to the plant, it has a positive effect on the process of photosynthesis and can increase the length and width of the fruit. According to the results of the experiment, in order to achieve the desired results, irrigation after draining 50% of the soil moisture, application of 4 tons per hectare of bentonite and 20 tons per hectare of manure are suggested for cultivation in Hirmand region.

Salinity stress is one of the most limiting non-living factors in wheat production. To overcome this problem, helpful information can be provided by understanding how genes respond and act in stress, to help plants withstand environmental stress. The biochemical and molecular response of wheat to salinity stress is diverse. Considering the effective role of the important family of transcription factors NAC and WRKY in dealing with stresses, this study evaluated the expression levels of three important genes from these families, TaWRKY10, TaWRKY53, and NAC2, as well as the content of chlorophyll, malondialdehyde, catalase, and polyphenol oxidase enzymes in bread wheat cultivars (Kalateh, Baharan, and Gonbad). The experiment was conducted in a randomized complete block design with four replications in greenhouse conditions. The main factor was salinity treatment (control, 9 and 12 deci-siemens) applied through irrigation after germination and plant establishment. The secondary factor was wheat varieties (Kalate, Gonbad, and Baharan). Sampling was performed to evaluate gene expression and biochemical traits. Real-Time PCR technique was used to check gene expression. In all tested cultivars, the chlorophyll content decreased with increasing salinity. The highest amounts of chlorophyll a and b were observed in the control treatment of the Kalate variety (14.5 and 18.2 mg/g fresh weight, respectively). Catalase and polyphenol oxidase enzymes, as well as the expression of TaWRKY10, TaWRKY53, and NAC2 genes, increased with salinity compared to the control in all three cultivars. The highest enzyme levels were observed in 12 deci-siemens salinity treatment of the Kalateh variety. The highest malondialdehyde amount (31 μmol/g fresh weight) was observed in the Baharan cultivar under 12 deci-siemens salt stress, indicating greater cell membrane damage in this cultivar. Based on the results, the Kalateh variety showed greater tolerance to salt stress compared to Baharan and Gonbad varieties. Transcription factors play a crucial role in enhancing plant resistance to salinity. The results of this study confirm the role of transcription factors in salinity resistance and could be utilized in developing and introducing tolerant wheat cultivars.

Drought stress is one of the most important factors limiting plant growth in the world and one of the most common abiotic stresses. Drought stress is a multidimensional stress that stimulates a wide range of physiological, biochemical and molecular responses in plants. In arid and semi-arid areas, the establishment and growth of young seedlings is completely affected by water deficit and drought stress. In this situation, the use of symbiosis of microorganisms, especially mycorrhizal fungi, can reduce the effect of drought stress via increasing the absorption of water and nutrients. Therefore, the aim of this study was to determine the effect of mycorrhizal fungi symbiosis on the absorption of the on the absorption of some macro and micro nutrients as well as the activity of antioxidant enzymes of Paulownia fortunei (Seem.) Hemsl., known as a fast-growing species.

This pot experiment was conducted in factorial form in a completely randomized design with three replications and two factors. The first factor included four levels of drought stress (no stress or control with full irrigation at 100% of crop capacity, mild stress with irrigation at 80% of crop capacity, moderate stress with irrigation at 60% of crop capacity and severe stress with irrigation at 40% of crop capacity) and the second factor which included two surfaces of using mycorrhiza (without and with arbuscular mycorrhizal fungi). Application of drought stress treatments was done based on the weight method. The investigated features included the measurement of soluble protein, catalase, peroxidase, superoxide dismutase enzymes, as well as the absorption of nutrients such as phosphorus, nitrogen, potassium, zinc, iron and manganese. The normal distribution and the homogeneity of the variance of the obtained data were checked using the Shapiro-Wilk test and Levene's test, respectively. Two-way analysis of variance was used to test the significance of the simple and interaction effect of the factors. Duncan's multiple range post-hoc test was used to compare the means.

The results of analysis of variance showed that the interaction effect of drought stress and mycorrhiza was not statistically significant on any of the traits. The simple effect of mycorrhiza on the changes of superoxide dismutase enzyme was significant, but it was not significant on other measured traits. The results showed that drought stress significantly increased the amount of soluble protein, peroxidase and superoxide dismutase activity. The highest concentration of soluble protein was related to severe stress treatment with a mean value of 38.95 mg/g leaf wet weight, and the lowest is related to the control or no stress treatment with a mean value of 31.45 mg/g leaf wet weight. However, no significant difference was observed between mild, moderate and severe stress treatments. About catalase enzyme no significant difference was observed between moderate and severe stress treatments, as well as between mild and moderate stress treatments. The highest concentration of peroxidase enzyme was related to severe stress treatment with a mean value of 3.77 mg/min per mg of protein and the lowest mean value (3.21 mg/min per mg of protein) was related to non-stress treatment (control). No significant difference was observed between the treatments of moderate stress and severe stress, as well as between the treatments of mild and moderate stress in terms of the concentration of peroxidase enzyme. The highest concentration of superoxide dismutase enzyme was related to severe stress treatment with a mean value of 0.176 mg/mol/min per mg of protein and the lowest value (0.108 mg/min/mg of protein) was related to the control. The concentration of superoxide dismutase enzyme in the treatment with mycorrhiza with a mean value of 0.159 mg/mol/min per mg of protein was significantly higher than of it in the treatment without mycorrhiza with a mean value of 0.140 mg/mol/min per mg of protein. Drought stress also led to the reduction of all measured nutrients. While, inoculation with mycorrhizal fungi increased nutrients except nitrogen at all levels of drought stress.

It was concluded that although the absorption of macro and micro nutrients by the seedlings decreased with the increase of drought stress levels, the use of mycorrhizal fungi could increase the absorption of macro and micro nutrients in drought stress conditions due to the better absorption of water by the hyphae around the roots of Paulownia seedlings. Therefore, it seems that the mycorrhizal fungi are very important in the absorption and metabolism of elements required by Paulownia seedlings, especially in stress conditions. Also, the inoculation of mycorrhizal fungi led to an increase in the activity of the antioxidant enzyme superoxide dismutase (SOD), which can increase the resistance of seedlings against drought stress.