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Introduction Intercropping reduces the application of chemical pesticides to control pests and weeds, reducing the environmental risks associated with chemical pesticide application (Himmelstein et al., 2017). Biochar is a soil amendment because of its potential to retain water and nutrients, prevent nitrogen leaching, increase soil fertility, and improve plant growth (Fang et al., 2018; Munoz et al., 2016). Other benefits of vermicompost are increased stability of soil resources, maintenance of production, reduction of environmental pollution, and increased soil biological activity too (Demir, 2019). Therefore, the purpose of this study was to investigate the quality of forage turnip (Brassica rapa var. rapa) leaves in different intercropping ratios of forage turnip and basil (Ocimum basilicum) using biochar as soil amendment and vermicompost. Materials and Methods A biennial study was conducted on the quality performance of forage turnip (Brassica rapa var. Rapa) in the form of split-plot factorial in a randomized complete block design with three replications in the research farm of Islamic Azad University of Karaj in two years (2018-2019). The treatments of this study include: intercropping in four ratio (100% forage turnip (monoculture), 90% forage turnip + 10% basil, 80% forage turnip + 20% basil, 70% forage turnip + 30% basil), in main plots, and vermicompost in two levels (15, 18.5 ton.ha-1) and biochar in two levels (No consumption and 5 ton.ha-1) which was placed in subplots. The forage turnip cultivar was PacFB05. In this study, Photosynthetic pigments were measured by the Arnon (1967) method, membrane permeability (Ferrat and Loval, 1999), relative moisture content (Bertin et al., 1996), soluble leaf sugars (Sheligl, 1986), catalase (Dazy et al., 2008) and soil respiration (Isermeyer, 1952). Using SAS software (Ver.9) for data analysis of a two-year experiment and analysis of means was done with Duncan’s test in significance at 5% probability level. Excel software was used to plot the graphs. Results and Discussion The results of this study indicated that by increasing the ratio of basil in intercropping, the quality traits of forage turnip leaves increased. Consumption of biochar and application of vermicompost at the level of 18.5 ton.ha-1 increased the quality of forage turnip leaves. The highest chlorophyll a ((17.52 mg.g-1Fw), chlorophyll b (8.76 mg.g-1Fw) total chlorophyll (26.38 mg.g-1Fw), carotenoids (6.91 mg.g-1Fw), relative water content (59.54%), of soluble sugars (69.43%), catalase (0.018 micromole Fresh weight/min) were due to the interaction of (70% forage turnip + 30% basil) × vermicompost 18.5 ton ha-1 × application of biochar. The highest value of membrane stability index was related to 100% forage turnip × vermicompost 15 ton ha-1 (4.85 (mol.ml-1.s-1)). The highest amount of soil respiration is associated with the interaction of vermicompost 18.5 ton.ha-1 × 70% forage turnip + 30% basil with value of 0.28 (micromole.gsoil-1.hour-1)), interaction of biochar ×70% forage turnip + 30% basil (0.32 (micromole.gsoil-1.hour-1)), and interaction of vermicompost of 18.5 ton.ha-1 × biochar 0.31 (micromole. g soil-1.hour-1). Due to the potential of biochar (water and food retention and prevent of nitrogen leaching) it can increase the availability of water and nutrients for the plant, which leads to increased photosynthesis of the plant and thus the quality of forage turnip leaves (Akhtar et al., 2015; Hammer et al., 2015). Vermicompost increases soil organic matter and the uptake of zinc, copper, iron, phosphorus, potassium, and nitrogen in soil. The presence of these elements in the soil and their absorption by the roots increases vegetative growth and leaf production in the plant, which causes the level of light absorption, photosynthetic level, the formation of hydrocarbons in the leaves, and the resulting growth also increases leaf quality (Theunissen et al., 2010). Conclusion The results of this study indicated that the application of vermicompost ​​18.5 ton ha-1 and biochar increased forage turnip quality, which is due to the availability of water and nutrients for forage turnip. The best intercropping ratio was related to 70% forage turnip + 30% basil, which can be said to be due to the increase in the percentage of basil and the competition of plants for better use of intercropping components of growth sources such as light, water, and food.

Abstract Background Oxidative stress mediated by reactive oxygen species (ROS) is a common denominator in arsenic toxicity. Arsenic stress in soil affects the water absorption, decrease stomatal conductance, reduction in osmotic, and leaf water potential, which restrict water uptake and osmotic stress in plants. Arsenic-induced osmotic stress triggers the overproduction of ROS, which causes a number of germination, physiological, biochemical, and antioxidant alterations. Antioxidants with potential to reduce ROS levels ameliorate the arsenic-induced lesions. Plant growth promoting rhizobacteria (PGPR) increase the total soluble sugars and proline, which scavenging OH radicals thereby prevent the oxidative damages cause by ROS. The main objective of this study was to evaluate the potential role of Arsenic resistant PGPR in growth of maize by mitigating arsenic stress. Methodology Arsenic tolerant PGPR strain MD3 (Pseudochrobactrum asaccharolyticum) was used to dismiss the ‘As’ induced oxidative stress in maize grown at concentrations of 50 and 100 mg/kg. Previously isolated arsenic tolerant bacterial strain MD3 “Pseudochrobactrum asaccharolyticum was used for this experiment. Further, growth promoting potential of MD3 was done by germination and physio-biochemical analysis of maize seeds. Experimental units were arranged in Completely Randomized Design (CRD). A total of 6 sets of treatments viz., control, arsenic treated (50 & 100 mg/kg), bacterial inoculated (MD3), and arsenic stress plus bacterial inoculated with three replicates were used for Petri plates and pot experiments. After treating with this MD3 strain, seeds of corn were grown in pots filled with or without 50 mg/kg and 100 mg/kg sodium arsenate. Results The plants under arsenic stress (100 mg/kg) decreased the osmotic potential (0.8 MPa) as compared to control indicated the osmotic stress, which caused the reduction in growth, physiological parameters, proline accumulation, alteration in antioxidant enzymes (Superoxide dismutase-SOD, catalase-CAT, peroxidase-POD), increased MDA content, and H2O2 in maize plants. As-tolerant Pseudochrobactrum asaccharolyticum improved the plant growth by reducing the oxidation stress and antioxidant enzymes by proline accumulation. PCA analysis revealed that all six treatments scattered differently across the PC1 and PC2, having 85.51% and 9.72% data variance, respectively. This indicating the efficiency of As-tolerant strains. The heatmap supported the As-tolerant strains were positively correlated with growth parameters and physiological activities of the maize plants. Conclusion This study concluded that Pseudochrobactrum asaccharolyticum reduced the ‘As’ toxicity in maize plant through the augmentation of the antioxidant defense system. Thus, MD3 (Pseudochrobactrum asaccharolyticum) strain can be considered as bio-fertilizer.

Salinity stress can be deemed as an important challenge extremely affecting crop growth as well as development. Therefore, it is important to improve its tolerance to salinity stress, in arid as well as semiarid regions. Thus, this experiment explored the influence of foliar usage of plant growth-stimulating substances with different concentrations (C: control, melatonin (M 1 : 100, M 2 : 200 and M 3 :400 µM) and silicon (Si 1 : 5.4, Si 2 : 10.8 and Si 3 : 16.2 mM)) on some physiological as well as biochemical attributes of Cyamopsis tetragonoloba L. (guar) seedlings under five salinity levels (S 1 : no-salt treatment, S 2 : 5, S 3 : 10, S 4 : 15 and S 5 : 20 dS m−1). With increasing salinity, shoot dry weight, F v /F m , F ′ v / F ′ m , ΦPSII, qp, qL, Rfd, ETR, photosynthetic pigments, membrane stability index, as well as relative water content were gradually reduced in salt-stressed guar, as comparison is made to the non-saline conditions. However, foliar usage of plant growth-stimulating substances was effective in improving guar tolerance to salinity by elevating the DPPH radical scavenging capacity and anthocyanin, thus enhancing membrane stability index, improving the electron's transport rate, reducing electrolyte leakage and decreasing the damage affecting the reaction center of PSII, as comparison is made with control. Such positive effects were exhibited in elevating growth under salinity stress. Si 3 treatment demonstrated the best response under salinity stress, as compared with the other treatments. Consequently, foliar usage of silicon or melatonin in salt-stressed guar seedlings can serve an efficient method to improve salt tolerance under salinity stress in arid and semiarid regions. [ABSTRACT FROM AUTHOR]

Background and Objectives: Low temperature has a major influence on survival and geographical distribution of plants and as an important environmental factor, it affects plant productivity. Physalis (Physalis peruviana L.) belongs to the Solanaceae family and is a tropical and subtropical plant that is affected by low temperatures at beginning and end of the growing season. These fruits are highly beneficial to human health due to their nutritional and bioactive compounds (antioxidants, vitamins A, B, C, E and K1, flavonoids and carotenoids), so it has gained attention for cultivation worldwide. Amino acids (L-Phenylalanine and cysteine) or selenium play important roles in plant resistance to low temperature. However, the role of L-phenylalanine (Phe) and cysteine (Cys) or selenium (Se) in regulating chilling tolerance and improve fruit quality of physalis is still unknown. In this study, the effects of Phe, Cys and Se on quality and antioxidant capacity of physalis fruit under low-temperature stress were investigated. Materials and Methods: The experiment was conducted in a randomized complete block design with three replicates. The seeds of physalis (Physalis peruviana L.) were sown in seedling trays containing peat moss under optimal conditions of 25±2 °C during the day and 20±2 °C at night. Different concentrations of L-phenylalanine (0.75, 1.5, and 2.5 mM, Phe), L-cysteine (0.25, 0.5, and 0.75 mM, Cys), or sodium selenate (0.25, 0.5, and 1 mg L-1, Se) were sprayed on the seedlings at the 4-5th true leaf stage. Distilled water was used as the control treatment. To induce chilling stress, plants with the basically same growth were transferred to a 4 °C climate chamber for 48 hours. The control group was grown under optimal conditions. After applying the chilling stress, the plants were returned to optimal growth conditions for 24 hours. Plants transplanted to the field and foliar sprayed three times (growth stage, flowering and fruit set stages) with amino acids and Se. After exposed plants to autumn chilling, fruits harvested during calix and fruit color change from green to orange stage, and plant height, yield and the quality characteristics of the fruit including carotenoid content, membrane stability index, titratable acidity, phenolic compounds and antioxidant activity were evaluated. Results: The results showed that low temperature stress significantly decreased fruit yield, carotenoids content and membrane stability index (MSI), and increased titratable acidity, phenols and flavonoids content and phenylalanine ammonia-lyase (PAL), superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities. Foliar spray of Physalis plants with Phe, Cys and Se under cold stress significantly increased plant height, fruit yield, antioxidant enzymes activity, MSI, carotenoids, phenolic compound and TA. The highest value of MSI (38.46 and 36.1) was obtained in fruit of plants treated with Se 0.25 and 0.5 mg L-1 under low temperature condition. The maximum phenol content (8.08 and 7.83 mg L-1) of fruit was observed with application of Phe 0.75 mM and Cys 0.25 mM in plants exposed to cold stress. Also, the highest antioxidant capacity was obtained in plant fruits treated with Phe 0.75 and 1.5 mM (60.8%), Cys 0.25 mM (60.26%) and Se 0.5 mg L-1, respectively under low temperature condition, and the lowest antioxidant capacity (50.5%) was observed in control plant fruits. Conclusion: The results of research showed that the foliar application of Phe, Cys or Se treatments, especially the levels of Phe 0.75 and 1.5 mM and Se 0.5 mg L-1 during seedling and field growing periods caused a significant increase in fruit yield, also increased the activity of antioxidant enzymes, phenolic compounds and the membrane stability index of fruits exposed to autumn cold and led to improvement of fruit quality. [ABSTRACT FROM AUTHOR]

Water deficit stress poses a significant challenge to wheat cultivation worldwide, necessitating the identification of indicator traits for plant productivity under such conditions. This study investigated the physiological and biochemical responses of four wheat varieties (C-306, DBW 110, DBW 136, and GW 451)under varying levels of water deficit stress (100%, 75%, and 35% FC). The results indicated that increasing water deficit stress resulted in notable decreases in physiological parameters such as the relative water content (RWC), chlorophyll content, chlorophyll stability index (CSI) and membrane stability index (MSI) at both the booting and grain filling stages. In response to water deficit stress, the plants increased their levels of proline, total soluble sugars (TSS), total phenol and free amino acids (FAA). Furthermore. oxidative damage, indicating that parameters such as proline concentration and malondialdehyde (MDA) content increased. Water deficit conditions markedly promoted the activities of key antioxidant enzymes, including catalase and peroxidase. Among the varieties, C-306 and DBW 110 were less affected by water deficit stress, as shown by significant changes in their physiological and biochemical parameters. These results highlight the importance of assessing physio-biochemical traits related to phenotypic water deficit stress tolerance in wheat varieties, providing valuable insights for breeding programs aimed at developing and selecting drought-tolerant cultivars. [ABSTRACT FROM AUTHOR]

Background: Oxidative stress mediated by reactive oxygen species (ROS) is a common denominator in arsenic toxicity. Arsenic stress in soil affects the water absorption, decrease stomatal conductance, reduction in osmotic, and leaf water potential, which restrict water uptake and osmotic stress in plants. Arsenic-induced osmotic stress triggers the overproduction of ROS, which causes a number of germination, physiological, biochemical, and antioxidant alterations. Antioxidants with potential to reduce ROS levels ameliorate the arsenic-induced lesions. Plant growth promoting rhizobacteria (PGPR) increase the total soluble sugars and proline, which scavenging OH radicals thereby prevent the oxidative damages cause by ROS. The main objective of this study was to evaluate the potential role of Arsenic resistant PGPR in growth of maize by mitigating arsenic stress. Methodology: Arsenic tolerant PGPR strain MD3 (Pseudochrobactrum asaccharolyticum) was used to dismiss the 'As' induced oxidative stress in maize grown at concentrations of 50 and 100 mg/kg. Previously isolated arsenic tolerant bacterial strain MD3 "Pseudochrobactrum asaccharolyticum was used for this experiment. Further, growth promoting potential of MD3 was done by germination and physio-biochemical analysis of maize seeds. Experimental units were arranged in Completely Randomized Design (CRD). A total of 6 sets of treatments viz., control, arsenic treated (50 & 100 mg/kg), bacterial inoculated (MD3), and arsenic stress plus bacterial inoculated with three replicates were used for Petri plates and pot experiments. After treating with this MD3 strain, seeds of corn were grown in pots filled with or without 50 mg/kg and 100 mg/kg sodium arsenate. Results: The plants under arsenic stress (100 mg/kg) decreased the osmotic potential (0.8 MPa) as compared to control indicated the osmotic stress, which caused the reduction in growth, physiological parameters, proline accumulation, alteration in antioxidant enzymes (Superoxide dismutase-SOD, catalase-CAT, peroxidase-POD), increased MDA content, and H2O2 in maize plants. As-tolerant Pseudochrobactrum asaccharolyticum improved the plant growth by reducing the oxidation stress and antioxidant enzymes by proline accumulation. PCA analysis revealed that all six treatments scattered differently across the PC1 and PC2, having 85.51% and 9.72% data variance, respectively. This indicating the efficiency of As-tolerant strains. The heatmap supported the As-tolerant strains were positively correlated with growth parameters and physiological activities of the maize plants. Conclusion: This study concluded that Pseudochrobactrum asaccharolyticum reduced the 'As' toxicity in maize plant through the augmentation of the antioxidant defense system. Thus, MD3 (Pseudochrobactrum asaccharolyticum) strain can be considered as bio-fertilizer. [ABSTRACT FROM AUTHOR]

Objective: The present research was conducted with the aim of evaluating the effect of melatonin treatment on the tolerance of basil plants to the excess of copper and zinc mineral elements. Methods: The effect of melatonin treatment (at two levels of 0 and 100 μM) on the tolerance of basil plants to the excess of copper (50 and 150 μM) and zinc (50 and 100 μM) mineral elements was evaluated using a factorial layout based on a completely randomized design with 3 replications under greenhouse conditions at the Graduate University of Advanced Technology of Kerman in 2017. Results: The triple effect of melatonin, zinc, and copper and the double effect of melatonin and zinc on the relative water content of leaves, total chlorophyll, carotenoid, protein, soluble and reduced sugar, anthocyanin and flavonoid, as well as the double effect of melatonin and copper and of zinc and copper on the parameters of leaf relative water content, membrane stability index, total chlorophyll content, protein content and soluble and reducing sugar content, anthocyanin, flavonoid, total glutathione, and redox were significant at the 1% probability level. Membrane stability indices and relative water content of leaves were improved by applying melatonin to the basil plant separately and together with copper and zinc metals. The amount of reducing sugars, chlorophyll, and carotenoids decreased under the influence of zinc and copper toxicity, although the use of melatonin enhanced these parameters. Copper toxicity caused a greater increase in the synthesis of plant biochemical compounds compared to zinc, indicating the more significant negative effect of copper toxicity as compared to excess zinc. Conclusion: Melatonin, through improving physiological characteristics—especially membrane stability, as well as flavonoid compounds, anthocyanin, and glutathione— led to the reduction of the negative effects of excessive amounts of copper and zinc on growth parameters, especially at the 50 μM metals concentration. [ABSTRACT FROM AUTHOR]

Cadmium is one of the most carcinogenic and hazardous heavy metals on the earth for causes many serious diseases and disorders in the plant body. The presence of Cd in the soil is equally harmful to the production of rice crops and human beings. A pot experiment was conducted to analyze the consequences of cadmium-induced stress on the antioxidative defense system in rice plants. The assessment of antioxidative defense mechanism based on the cadmium-induced stress in the range of 100 to 300 ppm while the parameters, Chlorophyll Content Index (SPAD), nitrogen (%), relative water content (%), membrane stability index (%), proline content (µg.g-1), and catalase activity (nm H2O2 mg-1.min-1) were used. The highest reduction in the Chlorophyll Content Index (CCI), nitrogen (%), RWC (%), and MSI (%) was recorded at the highest concentrations of Cd Cl2 (300 ppm). However, at the same time, an increase in proline content (µg.g-1) and catalase activity (nm H2O2 mg-1. min-1) were also detected at all the intervals of the study. The activity of CCI, amino acid, and enzyme were presented in % increase/decrease over the control of Cd-induced stress in rice plants. The reduction (%) in CCI (SPAD) and RWC (%) was recorded maximum at 75 Days after transplanting (DAT), while nitrogen (%) and MSI (%) were recorded at 50 DAT. However, the increase (%) in proline and Catalase activity was maximum at 75 and 50 DAT. [ABSTRACT FROM AUTHOR]

This study examined the effects of nickel (Ni) at 0, 25, and 50 mg.L-1 concentrations, applied alone or in combination with salinity (represented by NaCl at 0, 100, and 200 mM concentrations), on the biochemical traits of date palm. Hydrogen peroxide (H2O2), malondialdehyde (MDA), membrane stability index (MSI), peroxidase (POD) activity, superoxide dismutase (SOD), and proline content were among the parameters evaluated. The results revealed significant effects of nickel and salinity on the studied biochemical markers. Nickel at 50 mg.L-1 significantly increased H2O2 (0.87 µmol. L-1) and MDA (2.46 nmol.g-1) levels, while decreasing MSI (75.85%). Moreover, it enhanced POD (25.09 U.min-1.g-1) and SOD (3.78 U. min-1.g-1) activity, as well as proline content (4.35 µmol.g-1). Salinity at 200 mM significantly increased H2O2 (0.90 µmol L-1) and MDA (2.54 nmol.g-1) levels, decreased MSI (77.69%), and increased POD (27.61 U. min-1.g-1) and SOD (3.77 U.min-1.g-1) activity, along with increased proline content (4.54 µmol.g-1). Additionally, the combined application of nickel and salinity, particularly at higher concentrations, resulted in significantly increased biochemical responses compared to individual treatments. The findings highlight the interactive effects of nickel and salinity on the oxidative and antioxidant mechanisms in date palm plants. This study contributes to our understanding of plant responses to abiotic stressors and provides insights for optimizing date palm cultivation under challenging environmental conditions.

The duration and intensity of freezing stress are the most critical factors determining injury in autumn chickpeas, limiting their production and development. To evaluate the effects of freezing temperature and duration on the survival rate (SU%), as well as the physiological and biochemical characteristics of autumn chickpea seedlings, a study was conducted using five different temperatures (0, -6, -8, -10, and -12°C) and five different durations (1 h, 2 h, 3 h, 4 h, and 5 h) of exposure to freezing stress. The SU% of chickpea seedlings decreased to zero after exposure to temperatures of -10°C and -12°C for 5 hours. As the temperature decreased from -8°C to -12°C and the duration of exposure to freezing stress increased from 1 to 5 hours, the leaf membrane stability index decreased by 33%, 48%, 46%, 57%, and 58%, respectively. The highest and lowest total pigment contents were observed after 1 hour at 0°C and 5 hours at -12°C, respectively. The maximum photochemical efficiency of photosystem II (Fv’/Fm’) was not affected by temperatures as low as -8°C in any of the time treatments during the recovery period. However, this parameter’s value decreased as the freezing stress duration increased. At -12°C, the activity of ascorbate peroxidase, catalase, and peroxidase increased by 44.6%, 38.3%, and 33.0%, respectively, as the duration of stress was increased from 1 hour to 5 hours. A positive and significant correlation was observed between plant dry weight, membrane stability index, photosynthetic pigment content, and Fv’/Fm’ with SU% after exposure to freezing stress. The minimum temperature and the maximum duration of freezing stress tolerance in chickpea seedlings were observed at -12°C for two hours. Our findings confirm that prolonging the freezing duration disrupts the defense mechanisms of chickpea seedlings. Therefore, future studies on breeding chickpeas tolerant to freezing stress should concentrate on attributes strongly correlated with SU%. [ABSTRACT FROM AUTHOR]

The use of coumarin (COU) to alleviate the phytotoxic effects of salinity has great potential in improving the phytoremediation of saline and alkaline soils. 30-day bitter gourd plants were exposed to 15 dS m‒1 salinity of neutral (NaCl and Na2SO4) and alkaline (Na2CO3 and NaHCO3) salts. 60-day plants were harvested to record different growth, physiological and biochemical attributes. Salinity significantly subsided plant growth, chlorophyll, photosynthesis, and nutrient acquisition. Salinity induced notable oxidative damage in plants that displayed higher relative membrane permeability (RMP), accumulated elevated ROS (H2O2 and O2•‒) and MDA levels alongside intensified lipoxygenase (LOX) activity. The production of cytotoxic methylglyoxal was also significantly higher in plants under salinity. COU seed priming (50, 100 and 150 mg L‒1) promoted plant growth by circumventing oxidative injury and intensifying oxidative defense. Further, COU maintained the intricate balance between reduced (GSH) and oxidized (GSSG) glutathione to diminish ion excess toxicity, thereby facilitating the phytoremediation of saline soils. The lower doses of COU promoted methylglyoxal and ROS detoxification systems that, in turn, lessened the phytotoxic effects of salinity. COU restored ions homeostasis by augmenting osmotic adjustment in plants under salinity. [ABSTRACT FROM AUTHOR]

The duration and intensity of freezing stress are the most critical factors determining injury in autumn chickpeas, limiting their production and development. To evaluate the effects of freezing temperature and duration on the survival rate (SU%), as well as the physiological and biochemical characteristics of autumn chickpea seedlings, a study was conducted using five different temperatures (0, -6, -8, -10, and -12°C) and five different durations (1 h, 2 h, 3 h, 4 h, and 5 h) of exposure to freezing stress. The SU% of chickpea seedlings decreased to zero after exposure to temperatures of -10°C and -12°C for 5 hours. As the temperature decreased from -8°C to -12°C and the duration of exposure to freezing stress increased from 1 to 5 hours, the leaf membrane stability index decreased by 33%, 48%, 46%, 57%, and 58%, respectively. The highest and lowest total pigment contents were observed after 1 hour at 0°C and 5 hours at -12°C, respectively. The maximum photochemical efficiency of photosystem II (Fv’/Fm’) was not affected by temperatures as low as -8°C in any of the time treatments during the recovery period. However, this parameter’s value decreased as the freezing stress duration increased. At -12°C, the activity of ascorbate peroxidase, catalase, and peroxidase increased by 44.6%, 38.3%, and 33.0%, respectively, as the duration of stress was increased from 1 hour to 5 hours. A positive and significant correlation was observed between plant dry weight, membrane stability index, photosynthetic pigment content, and Fv’/Fm’ with SU% after exposure to freezing stress. The minimum temperature and the maximum duration of freezing stress tolerance in chickpea seedlings were observed at -12°C for two hours. Our findings confirm that prolonging the freezing duration disrupts the defense mechanisms of chickpea seedlings. Therefore, future studies on breeding chickpeas tolerant to freezing stress should concentrate on attributes strongly correlated with SU%.

The increasing utilization of nanoparticles (NPs) in agricultural practices has led to a surge in demand for nano-based products. Herein, we investigate the dose-dependent impacts of nickel hydroxide (Ni(OH)2)/nickel (Ni) NPs, synthesized using Asparagus racemosus Linn. leaf extract, on the seed germination and growth of Vigna radiata (Linn.) Wilczek. In all seed samples, 100% germination was observed in Treatment 1 (2.74 mg mL−1) and Treatment 2 (5.48 mg mL−1) of Ni/Ni(OH)2 NPs. However, in Treatment 3 (8.22 mg mL−1) and Treatment 4 (10.96 mg mL−1), the germination percentage was lower, reaching 80%. Further, Treatment 5 (13.70 mg mL−1) of Ni/Ni(OH)2 NPs showed a reduced germination rate of 60%, indicating a prolonged germination process at higher concentrations. Remarkably, the length of seedlings showed a significant increase in all experimental treatments compared to the control group, which received 5 mL of distilled water. Among the investigated parameters, Treatment 2 demonstrated the most promising outcomes, exhibiting the highest chlorophyll stability index (23.73%) and membrane stability index (67.89%) values, as well as the lowest root ion leakage (24.75%). These findings indicate that Ni/Ni(OH)2 has the capacity to enhance seed germination and foster seedling growth. [ABSTRACT FROM AUTHOR]

Legumes are sensitive to salt stress, especially in the early phases of growth. Brassinosteroids (BRs) or proline (Pro) have been shown to improve salt stress tolerance in several plant species when given exogenously. Therefore, two pot experiments laid out in 4 × 3 factorial in a completely randomised design, replicated three times were carried out on snap bean (Phaseolus vulgaris L.) cv. Valentino to examine the roles of BRs or Pro in improving the salt tolerance of snap beans. The first factor included four saline irrigation water levels viz. 0.0, 20, 40, and 60 mM sodium chloride (NaCl), while the second factor involved foliar application with 0.1 µM BRs or 30 mM Pro or distilled water as control. The results revealed that saline irrigation water reduced chlorophyll, membrane stability, relative water content, and yield. Exogenous BRs or Pro alleviated salt stress by reducing uptake and translocation of Na+ and Cl− while enhancing plant K+ assimilation. Increased water status, chlorophyll content, and antioxidant enzyme activity (SOD, POD, CAT) in leaves of snap beans may contribute to improved salt tolerance. These findings suggested that foliar treatment of brassinosteroids or proline could be an effective strategy to improve snap bean salt tolerance. [ABSTRACT FROM AUTHOR]

Drought stress is one of the major limitations to the growth and yield productivity of cereal crops. It severely impairs the early growing and grain -filling stages of wheat. Therefore, cost- effective and eco-friendly approaches for alleviating drought stress in cereal crops are in high demand. Polyamines, such as putrescine, have a significant effect on improving crop yield under drought-stress conditions. Therefore, the current study was executed with the aim of exploring the significance of putrescine in alleviating drought stress and improving yield- related traits in wheat. Two distinct wheat cultivars (Fakhar-e-Bhakkar and Anaj-2017) were treated with the foliar application of different concentrations (control, 0.5, 1.0, and 1.5 PPM) of putrescine (put) under two moisture conditions (well- watered and terminal drought stress). The results demonstrate that the imposition of terminal drought stress significantly reduces different physiological and yield- related traits of both wheat cultivars. The reduction of relative water content (RWC%), membrane stability index (MSI), leaf area, tillers per plant, biomass yield, number of spikelets per spike, 100-grain weight, grain yield per plant, and straw yield was greater in Anaj-2017 than in Fakhar-e-Bhakkar cultivar. The results further explain that the foliar application of increased concentrations of putrescine from 0.0 to 1.0 PPM gradually improved physiological and yield traits, whereas these traits declined with the application of putrescine at the highest dose (1.5 PPM). The exogenous application of 1.0 PPM putrescine improved the relative water content (19.76%), specific leaf area (41.47%), and leaf area ratio (35.84%) compared with the controlled treatment. A higher grain yield (28.0 g plant-1) and 100-grain weight (3.8 g) were obtained with the foliar application of 1.0 PPM putrescine compared with controlled treatments. The findings of this study confirm the protective role of putrescine against terminal drought stress. It is therefore recommended to use putrescine at a concentration of 1.0 PPM, which could help alleviate terminal drought stress and attain better wheat yield. [ABSTRACT FROM AUTHOR]

In the present study, the effect of foliar application of methyl jasmonate (MeJA) (0, 50, 100, and 200 µM) and salt stress (2 (non-stress), 4 and 8 dS m-1) on the improvement of salinity stress tolerance in narcissus was studied in the Research Greenhouse, Islamic Azad University of Isfahan (Khorasgan) during 2019-2020. In this research, a pot experiment was conducted, as factorial based on randomized complete block design with three replications. With increase in salinity, chlorophyll content, membrane stability index, leaf area, fresh and dry weight of shoots and roots and K concentration of narcissus decreased but Na and Cl concentrations increased in the leaves and bulbs. However, foliar-applied MeJA led to decreases in the concentration of Na and Cl and increase in the concentration of K in the plant tissue, resulting in improvement of the growth and plant biomass of the salt-stressed plants. Application of 50, 100 and 200 μM MeJA led to 5%, 14%, 7% reductions in leaf Na, 4%, 17%, 3% reductions in bulb Na, and 11%, 13%, 7% reductions in leaf Cl concentrations, respectively, of narcissus subjected to 8 dS m-1 salinity, compared to the absence of MeJA treatment. Moreover, application of 100 μM MeJA increased leaf K by 12%. Therefore, application of 100 μM MeJA was proven to be superior to other levels used in this study in increasing the tolerance of narcissus to saline conditions.

Drought stress is one of the major limitations to the growth and yield productivity of cereal crops. It severely impairs the early growing and grain -filling stages of wheat. Therefore, cost- effective and eco-friendly approaches for alleviating drought stress in cereal crops are in high demand. Polyamines, such as putrescine, have a significant effect on improving crop yield under drought- stress conditions. Therefore, the current study was executed with the aim of exploring the significance of putrescine in alleviating drought stress and improving yield- related traits in wheat. Two distinct wheat cultivars (Fakhar-e-Bhakkar and Anaj-2017) were treated with the foliar application of different concentrations (control, 0.5, 1.0, and 1.5 PPM) of putrescine (put) under two moisture conditions (well- watered and terminal drought stress). The results demonstrate that the imposition of terminal drought stress significantly reduces different physiological and yield- related traits of both wheat cultivars. The reduction of relative water content (RWC%), membrane stability index (MSI), leaf area, tillers per plant, biomass yield, number of spikelets per spike, 100-grain weight, grain yield per plant, and straw yield was greater in Anaj-2017 than in Fakhar-e-Bhakkar cultivar. The results further explain that the foliar application of increased concentrations of putrescine from 0.0 to 1.0 PPM gradually improved physiological and yield traits, whereas these traits declined with the application of putrescine at the highest dose (1.5 PPM). The exogenous application of 1.0 PPM putrescine improved the relative water content (19.76%), specific leaf area (41.47%), and leaf area ratio (35.84%) compared with the controlled treatment. A higher grain yield (28.0 g plant-1) and 100-grain weight (3.8 g) were obtained with the foliar application of 1.0 PPM putrescine compared with controlled treatments. The findings of this study confirm the protective role of putrescine against terminal drought stress. It is therefore recommended to use putrescine at a concentration of 1.0 PPM, which could help alleviate terminal drought stress and attain better wheat yield.

Drought stress is the most important environmental factor limiting the growth, development and yield of crop plants and horticulture. In this study, the induction of drought resistance in commercial cultivars (as scion) by the Ch1 rootstock was evaluated based on physiological and biochemical responses. Factorial experiment was performed in a completely randomised design (CRD) with three replications in the greenhouse. Plant materials consisted of five commercial grapevine cultivars (own-rooted plants of Black seedless, Flame seedless, Turkman seedless, Sultana and Shahani, and the scion of these cultivars grafted onto Ch1 rootstock). Drought stress treatment comprised stopping irrigation for 30 days from July to August, and not stopping irrigation was the control. Drought stress significantly reduced the membrane stability index (MSI) and the relative water content (RWC), and increased electrolyte leakage (EL), catalase, hydrogen peroxide, proline, ascorbic acid, guaiacol peroxidase, protein, sodium and potassium levels (P < 0.05). The EL and MSI in the Ch1 rootstock under drought stress decreased by 18.38% and 14.86% respectively. The Ch1 rootstock significantly increased the amount of proline, total protein and enzyme activity of guaiacol peroxidase and catalase in cultivars in a drought stress environment. The amount of hydrogen peroxide decreased in all cultivars grafted on Ch1 in both drought stress and non-drought stress environments, by 14.3% and 18.9% respectively. Sultana cultivar grafted on Ch1 rootstock showed the highest drought resistance. Therefore, it can be concluded that the Ch1 rootstock is recommended as a rootstock for inducing drought resistance in grapevine cultivar scions. [ABSTRACT FROM AUTHOR]

To investigate the effect of seed priming treatments on seed yield and it’s components in three bread wheat cultivars (Rijaw, Sardari and Karim) was studied under dryland condition at the Agricultural and Natural Resources Research and Education Center of Kermanshah during 2015-2016 and 2016-2017 growing season. The priming treatments consisted of gibberellic acid with 100 mg.L-1, 24-epiprasinolide 1 mg L-1, potassium chloride with 100 mmol L-1 and polyethylene glycol (PEG4000) with -2.3 and -2.9 bar, zinc sulfate 0.1 and 0.3%, 2 and 4 g urea L-1, ascorbic acid 100 mg L-1, hydropriming with distilled water and control (without seed priming). The highest percentage of crop ground cover was obtained with 39.9% of Sardari cultivar and 4 g urea L-1. The highest relative mean water content and flag leaf membrane stability index with 88.1 and 71.6% were related to Karim cultivar with 0.3% hydrated zinc sulfate treatment, respectively. The lowest mean rate of flag leaf water loss (30.6%) was obtained from Karim cultivar with zinc sulfate treatment of 0.3%. Two-year results showed that the highest mean seed yield (2801.4 kg.ha-1) belonged to Rijaw cultivar by seed priming treatment with 4 g.L-1 urea. The highest percentages of seed protein content by NIR method of Karim cultivar and treatments of urea with a concentration of 4 g.L-1 (12.32%), ascorbic acid (12.31%) and gibberellic acid (12.18%) with 100 mg.L-1 were obtained. In this study, based on the total measured traits of morphophysiological, yield and grain quality traits, nutient treatments of urea with a concentration of 4 g L-1, zinc sulfate with a concentration of 0.3% and ascorbic acid with a concentration of 100 mg.L-1 and potassium chloride 100 mmol L-1 were identified and recommended as appropriate and superior seed priming treatments.

In the present study, the effect of foliar application of methyl jasmonate (MeJA) (0, 50, 100, and 200 µM) and salt stress (2 (non-stress), 4 and 8 dS m-1 ) on the improvement of salinity stress tolerance in narcissus was studied in the Research Greenhouse, Islamic Azad University of Isfahan (Khorasgan) during 2019-2020. In this research, a pot experiment was conducted, as factorial based on randomized complete block design with three replications. With increase in salinity, chlorophyll content, membrane stability index, leaf area, fresh and dry weight of shoots and roots and K concentration of narcissus decreased but Na and Cl concentrations increased in the leaves and bulbs. However, foliar-applied MeJA led to decreases in the concentration of Na and Cl and increase in the concentration of K in the plant tissue, resulting in improvement of the growth and plant biomass of the salt-stressed plants. Application of 50, 100 and 200 μM MeJA led to 5%, 14%, 7% reductions in leaf Na, 4%, 17%, 3% reductions in bulb Na, and 11%, 13%, 7% reductions in leaf Cl concentrations, respectively, of narcissus subjected to 8 dS m-1 salinity, compared to the absence of MeJA treatment. Moreover, application of 100 μM MeJA increased leaf K by 12%. Therefore, application of 100 μM MeJA was proven to be superior to other levels used in this study in increasing the tolerance of narcissus to saline conditions. [ABSTRACT FROM AUTHOR]

Melatonin, being an endogenous signaling molecule plays important role in plant growth and stress alleviation. The present study was conducted to evaluate the ameliorative role of melatonin against Cr toxicity in maize seedlings. The Cr toxicity (50, 100 and 200 µM) severely affected hydroponically grown seedlings growth in a dose-dependent manner; however, the melatonin (0.5 and 1.0 µM) application markedly restored toxicity-induced growth retardation. Higher dose of melatonin (1.0 µM) was more effective in case of lower Cr toxicity (50 and 100 µM). Exposure of 200 µM Cr caused 45% and 43% reduction in shoot and root lengths and more than 80% reduction in biomass. In case of 200 µM Cr toxicity, application of 1.0 µM MT effectively restored shoot and root lengths reduction (from 45 to 30%) and biomass decline (from 80 to around 60%). Biomass restoration by 1.0 µM melatonin under 50 and 100 µM Cr was even more pronounced bringing it near to control plants having no Cr exposure. Further, both melatonin levels also improved root tips, root diameter, root volume and root surface area that had been damaged by Cr exposure. The melatonin also alleviated Cr-induced chlorophyll and carotenoids inhibition, improved relative water content, and markedly lowered proline and MDA content in shoots. Lower accumulation of MDA and proline, and greater membrane stability indices indicate that the melatonin conferred better plant growth by playing the role of antioxidant and detoxifying oxidative stress creating substances. Although antioxidant enzymes viz. SOD, POD, CAT and APX activities were also elevated by MT, this increase was not significantly different in the most of cases. No significant difference in NPK contents of shoot was observed by Cr and melatonin application indicating the growth retardation being caused directly by Cr intrinsic toxicity and not by nutrients deficiency. The melatonin-based amelioration of Cr toxicity in maize seedlings seems as the result of its nature as antioxidant, and not by activation/elevation of antioxidative enzymatic system. [ABSTRACT FROM AUTHOR]

Introduction In saline environments, plant growth and crop production are greatly reduced. Salinity, induces oxidative stress in the plants resulting in the production of reactive oxygen species (ROS), subsequently, cell membranes, proteins and nucleic acids are destroyed by ROS. Calcium plays a key role in processes that preserve the structural and functional integrity of plant cell membranes, stabilizes cell wall structures, regulates ion transport and selectivity, and controls ion-exchange behavior as well as cell wall enzyme activities. High concentration of Ca2+, stimulates its entry to the cell through ion channels. These channels are also permeable to sodium. Studies have shown that increasing Ca2+ concentration, decreases plasma membrane permeability to Na+ and changes the cell wall properties resulting in reduced Na+ transport by passive transport and decreased Na+ accumulation in the cell. The main objective is to identify the interaction effects of Na+/Ca2+ ions on morpho physiological characteristics of Bean plant and investigation the ameliorative effects of Ca2+ on salinity-induced damages. Material and Methods In order to evaluate the effects of different concentrations of Na+ (NaCl) including: 0, 50, 100 and 150 mM NaCl and Ca2+ (CaCl2) including: 0, 5, 10 and 15 mM CaCl2 on morph physiological characteristics of Bean an experiment was arranged as a factorial, based on completely random design. The plastic pots containing seeds were transferred to growth chamber with 600 µmol.m2.s-1 light intensity, 16/8h light and dark period, respectively. The pots were irrigated with water (without NaCl) for 14 days until emergence, then different concentrations of Ca2+ and Na+ were applied. In 6th week after sowing, plants were harvested and morphological and physiological characteristics were evaluated. The amount of some elements in roots and leaves were determined. Data were analyzed using MSTAT-C software. Results and Discussion The interaction of Na+ and Ca2+ on all morphological traits except root dry weight was significant. Toxicity and drought stress are the result of plant exposure to high concentrations of sodium. As water enters the cell, the turgor pressure increases causing the cell walls to extend irreversibly. The rate at which a cell expands is a function of its turgor pressure and cell wall properties. In all salinity levels, the use of 5 and 10 mM Ca2 + significantly increased plant height compared to control. In high salinity levels (100 and 150 mM NaCl), the role of calcium in increasing plant height decreased. In severity stress (150 mM NaCl), application of 10 mM Ca2 +, significantly increased shoot dry weight and leaf area compared to control. Results for root dry weight showed that, with increasing salinity, root dry weight at all levels of Ca2+, decreased. The highest root dry weight and total root length were attributed to the application of 5 mg Ca2 + in saline-free medium. Application of Ca2 + (mainly at 5 and 10 mM) moderated the negative effects of salinity on morphological traits. The elevated Ca2 + in the medium containing Na + ions, inhibits the binding of Na + to cell walls and the plasma membrane probably. In this way electrolyte leakage in the membrane may be reduced. Calcium improves the ability to synthesize and repair of cell walls with a more efficient function by participating in cell wall construction. In low and medium salinity, the use of 10 mM Ca2+ protected cell membranes from adverse effect of Na+, when compared to the control. Supplemental of 5 and 10 mM Ca2+ in all salinity levels, almost improved the leaf relative water content when compared to the control (non-applied Ca2+). Promotion in hydraulic conductivity, more stability and efficient membranes for selective absorption are the other features that were affected by Ca2+ supplemental. In high salinity, the use of 5 mM Ca2+ reduced the negative effects of salinity on total chlorophyll contain when compared to the control. At all salinity levels, application of 5 and 10 mM CaCl2 significantly reduced leaf proline content compared to control. In this regard, the effect of 5 mM Ca2+ was greater than 10 mM Ca2+. Addition of Ca2+ to the medium of plant exposed to salt stress, reduced proline concentration by increasing proline oxidase and following that reduction in glutamyl kinase activity and finally glutamine is used to synthesize more chlorophyll. At all salinity levels, the use of 5 and 10 mM Ca2 + significantly increased the activity of poly phenol oxidase compared to the control. Calcium promoted the synthesis and activity of many enzymes involved in defense mechanism and reduces the rate of proteolytic degradation. In this way Calcium modulates oxidative stress by altering plant metabolism. Results showed that the use of 5 and 10 mM Ca2 + significantly (P≤ 0.05) reduced the amount of Na+ in the plants (leaves + roots) when compared to control. This result for K+ accumulation was adverse. The obtained results go in line with the findings of other scientists. Wu and Wang, 2012 reported, Ca2+ decreased roots Na+ accumulation, increased shoots K+ accumulation, and enhanced the selective absorption and transport capacity for K+ over Na+ in the plant. Conclusion Salinity stress significantly reduced plant morphological characteristics but other traits such as proline and polyphenol oxidase increased. Membrane stability index, leaf relative water content, total chlorophyll content and leaf and root potassium content were significantly decreased with applying salinity stress. The use of Ca2+ ions, especially 5 and 10 mM, greatly reduced the negative effects of salinity. It seems that the use of calcium application can be considered as a simple and low cost method for reducing the adverse effects of salinity stress.

DOR: 98.1000/2383-1251.1399.7.99.13.1.1578.1585 Extended abstract Introduction: Soybean is a plant that has a moderate tolerance to drought stress. Drought stress is one of the most important abiotic stresses affecting soybean production by about 40%. In addition, drought stress reduces seed vigor as a result of stress conditions. Positive effects of mycorrhizal fungi on the increment of dry matter and plant biomass, especially in low-irrigated conditions and in dry areas have been proven. The reason for the increase in crop yield in mycorrhizal inoculated plants is their water balance in water deficit stress conditions and as a result, absorption of water and mineral elements. Rhizobium bacteria, carbohydrates, and other foods are catched from the phloem vessels and the received energy is used to convert nitrogen to ammonium ion and eventually amino acids. Japonicum rhizobium bacterium is not naturally found in soils of Iran and the bacteria should be added to the soil along with seeds. Materials and Methods: This experiment was carried out to determine the germination characteristics, seed vigor and its related traits in soybean Kosar cultivar grown under drought stress conditions and inoculation with mycorrhiza and bacteria with three replications during 2018. In the field experiment, drought stress included optimal irrigation (irrigation after 70 mm evaporation), moderate stress (irrigation after 110 mm evaporation) and severe drought stress (irrigation after 150 mm evaporation from class A evaporation pan), mycorrhizal fungus in three levels, mycorrhiza-free, and inoculation with glomus mosseae, Glomus intraradices and Rhizobium bacterium in two levels, including no inoculation and inoculation with Rhizobium japonicum. Results: The mean comparison showed that the seeds obtained under normal irrigation, inoculation with mycorrhiza and bacteria had the highest dry weight of radicle, plumule and seedling, percentage and germination rate. The lowest electrical conductivity of the seeds and the mean time of germination were obtained under these condition. Severe and moderate drought stress reduced stress tolerance index, root tolerance index and stem tolerance index, seedling vigor index and seed vigor index compared to optimum irrigation about 42-23, 38-18, 30-18, 50-26 and 41-21) percent, respectively. Inoculation with Glomus mosseae and Glomus intraradices increased the seed vigor index, radicle lentgh, plumule lentgh and seedling length compared to non-inoculation with mycorhizal fungi by 48-42, 27-26, 41-37 and 35-33 percent, respectively. Inoculation with Rhizobium japonicum increased radicle lentgh, plumule lentgh and seedling lentgh compared to non-inoculation with bacterium by 21%, 16% and 18%, respectively. The highest water percentage in seedling tissue was obtained under optimum irrigation conditions, inoculation with mycorrhizal fungi and inoculation with rhizobium bacteria. Conclusion: According to the results of this study, in all three different irrigation conditions to improve germination and increase seed vigor, the use of mycorrhiza fungi is effective especially glomus mosseae and inoculation with Rhizobium bacteria. Highlights: Germination characteristics, germination rate and duration of soybean Kosar cultivar on seeds obtained under different irrigation conditions were investigated. The effect of mycorrhiza and bacteria on seed vigor and related traits were evaluated under different levels of drought stress. The damage done to the seed membranes due to the interaction of irrigation and inoculation with mycorrhiza and bacterium was investigated.

Abstract Tagetes genus of Composite family consider one of the most favorite floriculture plants. Therefore, of particular interest examine the salt tolerance of this bedding and coloring agent plant. In this research, was report the role of glycinebetaine (GB) in attenuating the adverse impacts of salt stress in African marigold plant, along with their anti-oxidative capacities and biochemical attributes. The salt stressed African marigold (100 and 150 mM NaCl) was treated with GB at 200 mM, beside untreated control plants. According to the obtained results, the growth characters were negatively in salt stressed plants but a mitigate impact of GB were observed in this respect. Obviously, the morphological as well as some physiological characters were reduced with salinity treatments while GB treatment reverses these effects. Overall, the alleviate impact of GB on the negative impact of salt stress was enhanced through improving total phenolic and antioxidant enzyme activity. Further, it is concluded that GB concentration induces the activities of antioxidative enzymes which scavenged ROS increased under saline conditions.

The effect of silica nanoparticles (SiNPs) preservative solutions on the postharvest quality of rose cut flowers was investigated in this study. SiNPs were used at the concentrations of 0, 1, 2, and 3 mg·dm−3. Treatments of SiNPs increased flower longevity compared to untreated flowers. Relative fresh weight, relative water content, and water uptake were improved because of SiNPs treatments. The enhancement in chlorophyll content, total soluble sugars, as well as total phenol and flavonoid contents were positively correlated with SiNPs treatments. Malondialdehyde (MDA) content significantly increased by control roses relative to treated ones. Activities of peroxidase (POX) and polyphenol oxidase (PPO) enzymes significantly increased because of SiNPs treatments compared to the control. The treatment of 2 mg SiNPs·dm−3 maximized the longevity and improved the postharvest quality of cut roses. The results obtained suggested that SiNPs treatments could improve the longevity and postharvest quality of cut roses by reducing lipid peroxidation and motivating antioxidant machinery, therefore, retaining the membrane integrity.

Developing methods and approaches for preserving water relations, plant growth and productivity are essential under water deficit conditions. New nano-silicon complexes were synthesized (glycine nano-silicon, glutamine nano-silicon and histidine nano-silicon) to evaluate their foliar application in different concentrations (0, 1.5 and 3.0 mM) on growth, essential oil yield, water relations, and mineral composition of field grown feverfew (Tanacetum parthenium L.) under drought. Drought stress was imposed by different irrigation intervals (4, 8 and 12 days). By increasing irrigation interval, leaf relative water content and leaf water potential were declined which decreased biomass, leaf area, flower formation, essential oil production and health of the plant. Potassium and organic osmolytes accumulation under moderate drought stress alleviated the adverse effects water deficit condition. This was mainly due to proline and potassium accumulation in the plants' leaves. Although accumulation of soluble carbohydrates also was observed in the drought stressed plants, it was found to be a passive response to plant growth inhibition under drought. Moreover, drought stress decreased plant phosphorous content, but had no significant effect on plant nitrogen content. Foliar application of nano-silicon by improving the plant's water content and phosphorus absorption, recovered the plants' health and growth under moderate and severe drought conditions. In this regard, no significant differences were observed between 1.5 and 3.0 mM nano-silicon treatments. However, glycine nano-silicon treated plants represented higher drought tolerance (higher dry mass, leaf area, number and greenness) than the other complexes. Accordingly, foliar application of 1.5 mM glycine nano silicon for mitigating adverse effects of drought stress on feverfew was recommended. [ABSTRACT FROM AUTHOR]

Lichens are symbiotic organisms that effectively survive in harsh environments, including arid regions. Maintaining viability with an almost complete loss of water and the rapid restoration of metabolism during rehydration distinguishes lichens from most eukaryotic organisms. The lichen Xanthoria parietina is known to have high stress tolerance, possessing diverse defense mechanisms, including the presence of the bright-orange pigment parietin. While several studies have demonstrated the photoprotective and antioxidant properties of this anthraquinone, the role of parietin in the tolerance of lichens to desiccation is not clear yet. Thalli, which are exposed to solar radiation and become bright orange, may require enhanced desiccation tolerance. Here, we showed differences in the anatomy of naturally pale and bright-orange thalli of X. parietina and visualized parietin crystals on the surface of the upper cortex. Parietin was extracted from bright-orange thalli by acetone rinsing and quantified using HPLC. Although acetone rinsing did not affect PSII activity, thalli without parietin had higher levels of lipid peroxidation and a lower membrane stability index in response to desiccation. Furthermore, highly pigmented thalli possess thicker cell walls and, according to thermogravimetric analysis, higher water-holding capacities than pale thalli. Thus, parietin may play a role in desiccation tolerance by stabilizing mycobiont membranes, providing an antioxidative defense, and changing the morphology of the upper cortex of X. parietina .

To evaluate the effect of zinc oxide nanoparticles (ZnO) on morphological, physiological and seed yield of soybean and its components under saline conditions, an experiment a factorial experiment base on completely randomized design with three replications was conducted at the research greenhouse of the Faculty of Agriculture, Ferdowsi University of Mashhad, Iran in 2017. The first factor consisted of four levels of salinity (0, 4, 6.5 and 9 dS.m-1), and the second factor of three concentration of zinc oxide nanoparticles (ZnO) (0, 200 and 400 ppm). The results showed that foliar spraying 200 ppm nano-ZnO resulted in higher plant height, number of leaves and dry shoot weight than other nano-ZnO levels (zero and 400 ppm) in 6.5 and 9 dS.m-1 salinity. The highest stomatal conductance (11.2 μMH2O.m-2.S-1), relative water content (83.6%) and membrane stability index (80.7%) were obtained from application 200 ppm nano-ZnO at salinity level of 4 dS.m-1. Maximum number of seeds per plant (11.4) and seed weight per plant (2.24 g) were also recorded from 200 ppm nano-ZnO under salinity of 4 dS.m-1. At all levels of salinity stress, when enhancing concentration from zero to 200 ppm the amount of all studied traits were increased and with increased concentration of nano-ZnO from 200 to 400 ppm, all experimental traits were decreased due to toxicity effect induction of nano-ZnO on plant. In general, the results showed that sprying plant with 200 ppm zinc oxide nanoparticles improved soybean growth at 6.5 and 9 dS.m-1salinity stresses.

The gene NCED1 encodes 9-cis-epoxycarotenoid dioxygenase, which catalyzes oxidative cleavage of 9-cis-epoxycarotenoids neoxanthin and violaxanthin to xanthoxin, a key step in the biosynthesis of abscisic acid in higher plants. In the present study, the complete NCED1 of 1 917 bp was cloned and characterized from rice (Oryza sativa L. cv. N22) as no earlier reports were available for its characterization from indica cultivar. The NCED1 had no intron and encoded a protein of 639 amino acids with a predicted molecular mass of 68.62 kD and pI of 6.07. The aliphatic index and grand average of hydropathicity were found to be 77.04 and -0.148, respectively. Multiple alignment analysis revealed that the sequence shared a high identity with the Oryza sativa japonica group (100 %) followed by Triticum aestivum (90 %), Hordeum vulgare (90 %), and Zea mays (89 %). The enzyme had a RPE65 domain of 476 amino acid residues. The RPE65 domain requires Fe(II) as a cofactor coordinated with 4 histidine residues and 3 glutamic acid residues. The phylogenic tree shows that NCED1 of japonica rice and NCED1 of indica rice were in the same group. They might have been evolved from a common ancestor. Analysis with a PSORT III tool shows that NCED is a chloroplastic protein. The real-time quantitative PCR and RNA-sequencing studies show that the expression of NCED1 was progressively reduced with increasing water stress, and a negative correlation between expression of OsNCED1 and severity of stress was established. Further, NCED1 expression negatively correlated with abscisic acid (ABA) accumulation under water stress whereas in some other species its expression increased along with ABA accumulation. This might be due to feedback inhibition of the ABA biosynthesis in rice.

Water stress is one of the major environmental stresses that affect agricultural production worldwide, especially in arid and semi-arid regions. This research investigated the effect of water deficit, induced by PEG-6000 on wheat genotypes (GA-2002, Chakwal-97, Uqab-2000, Chakwal-50 and Wafaq-2001) grown in modified MS medium solution. Osmotic stress caused a more pronounced inhibition in leaf relative water content and leaf membrane stability more sensitive (index in Wafaq-2001 and Uqab-2000) genotypes compared with the tolerant (Chakwal-50, GA-2002 and Chakwal-97) genotypes. Upon dehydration, an incline in proline, total soluble sugar, total soluble protein, superoxide dismutase, peroxidase, catalase and malondialdehyde activity content were evident in all genotypes, especially at osmotic stress of −8 bars. The observed data showed that status of biochemical attributes and antioxidant enzymes could provide a meaningful tool for depicting drought tolerance of wheat genotypes. The present study shows that genotypic differences in drought tolerance could be likely attributed to the ability of wheat plants to induce antioxidant defense under drought conditions. In order to develop genotypes with stable, higher yields in dry farming conditions, it is necessary to characterise genetic resources based on drought adaptation, determine suitable genotypes, and then use them in breeding programmes.

Mungbean is one of the most powerful pulses providing substantial protein for human diets and fixing N to the soil, improving nutritional food security and agricultural sustainability. The production of summer mungbean in the tropics and subtropics is adversely affected by drought due to water scarcity caused by various factors as well as lack of rainfall. Irrigation at different growth phases is not a suitable solution. An environmentally friendly and economically viable answer is a convenient irrigation management option that will be available to farmers together with drought-tolerant genotypes. The study considered to determine the effect of differences between drought-tolerant and drought susceptible genotypes on water productivity response and physiological traits in mung beans. To quantify seed yield-related to irrigation at different growth stages eventually to quickly determine the most appropriate irrigation stage. One water stress tolerant mung bean genotype (BMX-08010-2) and one sensitive genotype (BARI Mung-1) were grown in the field with four different irrigation schedules along with water stress conditions (no irrigation) under rain shelter at Regional Agricultural Research Station, BARI, Ishwardi, Pabna, Bangladesh. The experiment was laid out in split plots with three replications, with irrigation schedules assigned in the main plot and mung bean genotypes assigned in the side plots. Water use efficiency ranged from 3.79 to 4.68 kg ha−1 mm−1 depending on irrigation regime, and mung bean seed yield of mung bean Water stress decreased plant water status, photosynthetic pigment and membrane stability index, and increased proline soluble sugar content. Treatments that received irrigation during two or three phases (I3 or I4) gave significantly higher yields than those that received irrigation during only one stage (I1 and I2) with the lowest yield. While the yield obtained ranged between 1145.44 kg ha−1 with seasonal irrigation of 277 mm (I4) and 555.14 kg ha−1 without irrigation (I0). The flowering stage (I3) was recorded as the most sensitive growth stage with an 18.15% yield reduction compared to the treatment with triple irrigation (I4). Also, depending on the irrigation sources, at least two irrigation phases should be provided at the triple leaf stage (I2, i.e., 20 DAS) and at the flowering stage (I3, i.e., 35 DAS) to achieve the highest yield. Genotypes that maintained the higher performance of physicochemical traits under water stress provided higher seed yield and promoted drought tolerance. Therefore, these parameters can be used as physiological and biochemical markers to identify and develop superior genotypes suitable for drought-prone environments.

Maize (Zea mays L.) is an important crop used for feeding humans and cattle globally. Deficiency of potassium (K) and zinc (Zn) adversely impacts the maize crop productivity and quality. However, the application of these nutrients shows variant responses in different maize cultivars. To understand this perspective, the current study aimed at investigating K and Zn’s optimal concentration in different hybrid and inbred maize cultivars. The treatments were based on three zinc levels (0, 6, and 12 mg Zn kg−1) and K levels (0, 30, and 60 mg kg−1), and their respective combinations. The experiment results showed that combined fertilization approaches of Zn and K (Zn12K60) improved the plant biometric, and physiological attributes of maize crop. The results revealed a significant increase in plant height (45%), fresh weight (70%), and dry weight (45%). Similarly, physiological attributes significantly improved the relative water content (76.4%), membrane stability index (77.9%), chlorophyll contents (170%), and photosynthetic rate (130%) in both inbred and hybrid genotypes. Furthermore, Zn and K (Zn12K60) increased transpiration rate (E), stomatal conductance (Ci), and internal CO2. In conclusion, maize hybrids (Neelam and DK-6142) were observed best compared with inbred (Afghoi and P-1543) cultivars with the combined application of Zn and K (Zn12K60). Thus, these inbred varieties should be preferred for fodder requirement with optimum fertilizer (Zn12K60) application in Zn deficient soils.

This experiment was carried out to analyze some primary and secondary compounds in various organs of Lactuca serriola during phenological vegetative growth stage. After collecting aerial parts of L. Serriola from the farms in Vamenan village in Azadshar, various organs such as root, stem, and leaf were dried and powdered separately. Also, mixed organs were considered as another treatment for comparison. Then various organs of L. serriola and a mixture of them were analyzed qualitatively for primary metabolites like organic matter, raw ash, protein, proline, starch and soluble sugar as well as membrane stability index and some secondary metabolites like total phenols and anthocyanin. Results showed that various organs of L. serriola had a various content of primary and secondary metabolites as well membrane stability index. On the basis of the findings, the highest and lowest contents of organic matter and raw ash were obtained in leaf, respectively. The highest content of protein, starch and compatibility osmotic of soluble sugar and proline also were found in the leaf organ. The highest content of total phenols and anthocyanin were obtained in leaf showing a positive and significant correlation with membrane stability index. Regarding the high biomass generated from L. serriola, it is suggested to analyze the other chemical compounds in this plant. Complimentary studies are required to exploit the application of these compounds as bio herbicide.

To evaluate of spermidine polyamine (SPD) foliar spraying effect on physiological indices and soybean yield (cv.'Caspian') under low-irrigation condition, a split-plot experiment was conducted based on randomized complete block design with three replications in Chapak rood, Joybar, Mazandaran province, in the year of 2016. The treatments incorporated the four levels of irrigation (100, 70, 50 and 30% of water requirement) as main plots and the three levels of foliar spraying SPD (0 (control), 0.5, 1 mM) as sub-plots. The evaluated parameters includes leaf number, pod number per plant, plant height, seed number per plant, the thousands seeds weights, the dry matter yield in a single plant, seed yield in a single plant, membrane stability index (MSI), relative water content (RWC), electrolyte leak age (EL), malondialdehyde (MDA), and hydrogen peroxide (H2O2). The results displayed that the application of SPD in various concentration had a significant effect on all characteristics except leaf numbers under low-irrigation conditions. In the evaluation of the interaction effects, the exhibited results showed that between low- irrigation and SPD, the SPD spraying concentration at the rate of 1 mM by reduced irrigation conditions from normal water requirement (100%) to its 30% requirement will result in significant incense in the pod number, seed number per plant, one thousands seeds weight, and dry matter yield by 90, 90, 50 and 20%, respectively. Also, RWC and MSI increased up to 63% and 1.13 times, respectively, while EL decreased by 16% as compared to no-SPD conditions. With the decrease of irrigation rate to 30% water requirement, the SPD concentration of 0.5 mM made seed yield to increase up to 90%, while H2O2 and MDA decreased to 67% and 34%, respectively that is the indication of plant drought tolerance. In sum, the results indicated the positive effect of the application of SPD imp roved drought tolerance in soybean (cv.'Caspian') under low-irrigation condition through the improvement of physiological characteristics and yield components. [ABSTRACT FROM AUTHOR]