Proline

In order to investigate the effect of ascorbic acid and proline on the germination indices of Aquilegia columbine seeds under salt stress conditions, the present research was conducted as a factorial experiment based on a completely randomized statistical design with three replications. The experimental treatments included ascorbic acid and proline each with concentrations of zero, 50 and 100 mg/liter and salinity stress caused by sodium chloride salt with levels of zero, 50 and 100 mg/liter.  The evaluated traits included germination indices (percentage of germination, radicle length, shoot length), proline amount and catalase and peroxidase enzymes activity. The results showed that the highest percentage of germination, radicle and shoot length were obtained in proline 100 mg/l in the absence of salt treatment. The highest proline amount was in proline 100 mg/L in sodium chloride salinity stress 100 mg/L treatment. The highest catalase and peroxidase enzymes activities were obtained in 100 mg/l ascorbic acid in the absence of salt stress treatment. Therefore, according to the results of the research, it is possible to recommend the use of proline 100 mg/liter under salinity stress conditions caused by sodium chloride salt to improve germination indicators (germination percentage, radicle length, shoot length) and enzyme activity of Aquilegia columbine plant seeds.

In order to investigate the effect of biofertilizers and zinc foliar application on the physiological characteristics and nutrient concentration of black cumin under different irrigation regimes, a split factorial experiment was conducted in the form of a randomized complete block design with three replications in Zarghan, Fars province, in 2017 and 2018. Irrigation regimes (providing 100, 75 and 50% of the irrigation water requirement) as the main plot and biofertilizer (mycorrhiza, Phosohate Barvar2, mycorrhiza + Phosohate Barvar2, no biofertilizer) and foliar application (zinc foliar application, no foliar application) were considered sub-plots. In both years of the experiment, the reduction of irrigation water decreased the nitrogen concentration of aerial organs (45%), chlorophyll a (70%), soluble protein (37%), relative water content (40%), biological yield (46.6%), and grain yield (56%) of black cumin. However, it increased traits such as proline (1.35 times), soluble sugar (60%), and electrolyte leakage (1.1 times). Biofertilizer application, especially in combination (mycorrhiza+ phosphate Barvar2), and zinc foliar application increased all the traits mentioned except electrolyte leakage. So in 50% irrigation, the combined application of biofertilizer compared to no application of biofertilizer increased the grain yield by 46% and 49.7% in 2018 and 2019, respectively. The results showed that the application of biofertilizers and zinc foliar application moderates the negative effects of drought stress in black cumin by improving nutrient absorption and physiological characteristics.

In order to investigate the effect of drought stress and biofertilizers from Mycorrhiza, azotobacter and azospirillum on the yield and biochemical characteristics of two wheat cultivars, a randomized complete block design in the form of split-factorial experiment was conducted with three replications in the crop year 2014-2015 in Poldakhter city. Drought stress in the main plots consisted of three levels of full irrigation, interruption of irrigation from the spike stage and interruption of irrigation from the seed filling stage. The sub-plots factorially included biofertilizer factor in four levels of control (without fertilizer), mycorrhiza inoculation, mycorrhiza+aztobacter inoculation, mycorrhiza+azespirillum inoculation, and the cultivar factor included Chamran and Behrang cultivars. Drought stress in the flowering stage caused a decrease in the content of chlorophylls and most elements, including nitrogen, phosphorus, potassium, copper and manganese, in shoots and seeds, but increased the content of proline and antioxidant enzymes. The content of most of the elements in aerial parts and seeds and the concentration of proline and antioxidant enzymes were higher in the Chamran variety than Behrang. The simultaneous use of mycorrhizae and growth-stimulating bacteria increased the content of most elements in shoots and seeds compared to the control treatment, but it decreased the concentration of proline and antioxidant enzymes. The mutual effects indicated the different responses of cultivars to the levels of biofertilizer in different drought stress treatments. In general, the Chamran variety is recommended by combining mycorrhiza with Azotobacter or Azespirillum.

Artemisia haussknechtii Boiss, is a valuable medicinal plant native to Iran. Although it belongs to the genus Artemisia, there have been few studies on its populations. This study aimed to investigate the ecomorphological and physiological diversity of this species by collecting samples from 17 populations across central and western Iran, specifically in the provinces of Isfahan, Chaharmahal and Bakhtiari, Markazi, Lorestan, and Kohgiluyeh and Boyer-Ahmad. Using Principal Component Analysis (PCA) of the morpho-physiological traits, we evaluated the separation between the populations. The first three axes accounted for 76.01% of the variance. Cluster analysis revealed that the populations of A. haussknechtii could be categorized into three main groups: 2, 7, and 8. The findings indicated a negative correlation between plant height and elevation above sea level. Additionally, leaf length and width showed negative correlations with average annual temperature and wind speed, while positively correlating with nitrogen levels and soil organic matter. Proline content was positively correlated with average annual temperature and negatively correlated with soil organic matter and nitrogen. Furthermore, the essential oil content exhibited a positive relationship with the average annual total of sunny hours but a negative relationship with soil saturation point moisture. Overall, the populations of A. haussknechtii demonstrated adaptability to varying environmental conditions through morpho-physiological alterations such as changes in plant height and leaf dimensions, along with variations in proline levels.

Salinity is one of the major factors that adversely affect the performance and growth parameters of most agricultural crops worldwide. Plant growth and the levels of secondary metabolites are influenced by salt stress. The aim of this study was to investigate the effect of soil organic amendments on some physicochemical traits of Salvia viridis L. plants under salt stress. The present study was conducted in a factorial design in a completely randomized manner. The treatments included five levels of organic amendments (control without any amendment, half and one gram of seaweed extract per liter of water, 20% volume of pot cow manure compost, and 20% volume of pot vermicompost) and three levels of soil salinity (3, 6, and 9 deci-Siemens per meter) with three replications in a greenhouse. The control treatment had no fertilizer. The findings indicated that as the salinity level increased, growth parameters (fresh weight, dry weight of stem and leaf, leaf area), chlorophyll content, and proline decreased, while malondialdehyde increased. The highest fresh and dry weight of stem and leaf, proline content, and essential oil percentage were obtained in plants treated with seaweed extract, while all amendments showed higher chlorophyll content compared to the control. Furthermore, among the investigated treatments, seaweed extract at a concentration of 1 milligram per liter proved to be more effective in preserving the plant from the adverse effects of salt stress and improving its growth characteristics.

Drought, one of the major ecological limiting factors, has a significant effect on the growth and secondary metabolic process of medicinal plants. Water stress reduces the size, density, leaf surface of the plant and reduces the biomass, and not only changes the plant structurally, but also leads to fluctuations in their secondary chemical compounds. The present study was carried out to investigate the effect of using brassinolides and surfactant on drought stress tolerance on Sarkhargol medicinal plant at Islamic Azad University of Mahabad during 2016 - 2017. The studied factors include dryness at three irrigation levels of 70, 120 and 170 mm, evaporation from class A pan as the main factor, surfactant consumption at two levels (0 and 0.5 liters per hectare) and 24-epibrassinolide at three levels (0, 0.01 and 0.1 μmol) were as secondary factors. According to the results of the present study, drought stress had a decisive role in reducing the properties of Sarhargol medicinal plant, as well as the main effects of brassinolide, surfactant solution and drought stress according to the content of soluble sugars, proline, glycine betaine, amino acids, lysine and methionine. They had Due to the limitation of water resources, irrigation after 120 mm, use of brassinolide and surfactant can have a positive role in removing the damages of drought stress. In addition, brassinolide and surfactant led to increased tolerance to drought stress in Sarhargol medicinal plant, which led to relative resistance to drought and stability of the yield of dry matter of the plant and its essential oil.

Plants employ various defensive strategies to cope with heavy metal stress in their growing environment. In this study, proline content, antioxidant enzyme activities, and phenolic compound levels were analyzed in saffron corms exposed to varying concentrations of cadmium stress. Saffron corms were cultivated under cadmium stress at concentrations of 0, 0.25, 0.5, 1, 2, 5, 10, and 20 mM, and samples were collected on days 0, 5, 10, 20, and 30 after cultivation. Antioxidant enzyme activities, proline levels, and phenolic content were measured. Statistical analysis was performed at a significance level of P < 0.05 using SPSS software. The results revealed significant increases in the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), polyphenol oxidase (PPO), guaiacol peroxidase (GPX), phenylalanine ammonia-lyase (PAL), as well as in proline content and phenolic compound accumulation, in response to cadmium treatments. The activity responses of PPO, CAT, APX, PAL, and GPX enzymes followed a biphasic pattern, while phenolic compound accumulation exhibited a linear regression trend. In contrast, the activities of SOD and proline accumulation conformed to a flattened exponential function. Maximum activities of PPO, CAT, APX, and PAL enzymes were observed at a cadmium concentration of 10 mM in corms harvested after 30 days of stress exposure. Similarly, the highest SOD activity and proline accumulation were recorded in 30-day-old corms, with phenolic compound accumulation significantly increasing with higher cadmium concentrations, albeit with varying rates depending on the duration of exposure. The observed changes in enzyme activities during growth suggest activating regulatory mechanisms in saffron to mitigate cadmium stress. The antioxidant roles of enzymes, proline, and phenolic compounds are critical in Safran’s response to cadmium-induced stress. Given that high cadmium levels induce the production of reactive oxygen species (ROS), the saffron plant enhances the synthesis of antioxidant enzymes to neutralize destructive radicals effectively.

In order to evaluate the effects of irrigation regims and nitrogen biological and chemical fertilizers on grain yield (paddy) and some physiological traits, an experiment was conducted in the form of split split plots in a randomized complete block design with three replications in two years ( 2017 and 2018). It was carried out in a research farm of the National Rice Research Institute of I. R. Iran in Rasht. Experimental factors include irrigation regime at three levels without stress (permanent flooding) and irrigation intervals of 10 days and 15 days as the main factor, fertilizer at three levels including inoculation of seedlings with biofertilizer, inoculation of seedlings with biofertilizer + 50% fertilizer Chemical nitrogen required by the plant and 100% chemical nitrogen fertilizer required by the plant) as a secondary agent and rice cultivar at two levels including Hashemi and Gilaneh as a secondary agent. The highest grain yield in the first year (4.14 t/ha) and the second (3.99 t/ha) was recorded in the treatment of 100% of the chemical fertilizer supplying the plant with nitrogen requirements, flooding conditions and Gilaneh cultivar, which was treated with inoculation Transplant roots with biofertilizer + 50% of chemical fertilizer supplying nitrogen required by the plant (combined treatment) in the first year (3.93 t/ha) and the second (3.85 t/ha) were in a statistical group. Consumption of biofertilizer along with chemical nitrogen fertilizers, in addition to producing sufficient yield and improving the efficiency of nitrogen uptake, was able to reduce the use of nitrogen chemical fertilizers by 50%.

In order to investigate the effect of drought stress on the enzymatic and non-enzymatic antioxidant system of six grape varieties, a factorial experiment was conducted based on a completely randomized design with three replications under greenhouse conditions. In this experiment, the treatments included six grape varieties (Asgari, Khalili, Yaquti, Pikami, Turkmen 4 and Suzak) and four levels of drought stress (normal conditions (100% of the farm capacity), low stress (75% of the farm capacity), medium stress (50% of the farm capacity) and severe stress treatment (25% of the farm capacity). The results showed that the traits of proline, malondialdehyde, catalase enzymes and ascorbate peroxidase enzymes improved with increasing stress intensity. increased significantly. On the other hand, the content of total phenol decreased significantly with the increase of the intensity of stress. Among the cultivars studied, Yaqouti cultivar is more resistant to drought than other grape cultivars in terms of the studied indices. The highest amount of catalase enzyme activity was recorded in Yaqouti cultivar, so that its catalase enzyme activity at the levels of 75, 50 and 25% of the agricultural capacity increased by 13, 12 and 46% respectively compared to the 100% agricultural capacity. According to the results of this research, it seems that Yaghuti cultivar is more drought tolerant than other cultivars. Since this toleration mechanisms located in leaf of Yaghuti, it is necessary to carry out additional tests when using as rootstock.

In order to investigate the effect of foliar application of different levels of ethanol and methanol on the biochemical characteristics of Digitalis purpurea L., an experiment was conducted based on a completely randomized design with three replications at the University of Zanjan research greenhouse. The treatments consisted of two levels of ethanol (5 and 10%) and methanol (5 and 10%), along with a control treatment (distilled water). The results showed that the maximum amount of total chlorophyll (1.78 mg/g), total carotenoid (0.10 mg/g), total phenol (15.35 mg/g), total flavonoid (58. 2 mg/g) and antioxidant activity (43.76%) were obtained under a 10% methanol treatment. The highest amounts of proline (4.47 mg), soluble sugar (76.20 mg/g), relative water content (76.02%) and leaf nitrogen (1.61%) were observed under a 10% ethanol treatment. The ion leakage index (15.21%) with foliar application of 10% ethanol and catalase enzyme (1.66 mg/g protein) and peroxidase enzyme (0.34 mg/g protein) activity showed a decrease with foliar application of 10% methanol. According to the results, the application of different levels of hydroalcohols improved the biochemical properties of Digitalis purpurea L.

Salinity is one of the most important environmental stresses, the increasing spread of which reduces the growth and yield of agricultural plants, in this regard, identifying sugar beet cultivars tolerant to salinity stress to improve quantitative and qualitative yield is of particular importance. For this purpose, research was conducted to investigate the physiological characteristics of some sugar beet genotypes under salt stress in 2019. This experiment was carried out factorially in the form of randomized complete blocks with three replications in Mohaghegh Ardabili University under greenhouse conditions. The experimental factors included different genotypes of sugar beet (9 genotypes) as the first factor and salinity stress as the second factor at four levels (control and 4, 8 and 12 dS/m). The results showed that the effects of salinity stress on chlorophyll content, soluble protein, proline content, soluble sugars and the activity of antioxidant enzymes (catalase, peroxidase and polyphenol oxidase) of different sugar beet cultivars were significant. Higher levels of salinity stress (12 dS/m) caused a significant increase in soluble protein, proline content, soluble sugars and activity of catalase, peroxidase and polyphenol oxidase enzymes compared to other levels of salinity stress and the control treatment. Whereas, the highest content of chlorophyll a, b and total chlorophyll was observed in cultivars number 15 and 4 in the treatment of not applying salt stress. Among the studied genotypes, genotypes No. 6, 15 and 20 had the highest activity of antioxidant enzymes under the condition of 12 dS/m salinity stress. Therefore, at higher levels of salinity stress, resistant sugar beet cultivars prevent the reduction of photosynthetic pigment content by improving the content of compatible osmolytes and antioxidant activities through correct membrane structure.

St. John's wort (Hypericum perforatum L.) is a medicinal plant that is more than 2000 years old. Drought stress is one of the most limiting environmental factors in the growth and production of plants. Plant symbiosis with mycorrhiza fungi and foliar spraying of essential elements can be one of the most effective solutions to deal with drought stress. This research also aims to evaluate the effect of mycorrhizal fungus and zinc sulfate foliar spraying on some biochemical traits and economic yield in St. John's wort under different irrigation regimes in a split factorial experiment with a basic randomized complete block design in three repetitions carried out during the three cropping years of 2018, 2019 and 2020. The main factor is irrigation regimes at three levels (100, 75 and 50% of irrigation needs); sub-factors were ZnSO4 foliar spraying at three levels (0, 3 and 6 per thousand) and inoculation with an AMF (Funneliformis mosseae) at two levels (inoculated and uninoculated). The results showed that the triple interaction of irrigation regimes + foliar spraying + mycorrhiza in all three years had a significant effect on chlorophyll content, proline, soluble sugars, malondialdehyde and economic yield. Increasing irrigation stress had a reducing effect on chlorophyll content, economic yield, and the relative water content of leaves, but on proline, soluble sugars and malondialdehyde had an increasing effect. At each stress level, the highest economic yield was obtained in the treatment of 6 per thousand foliar spraying + inoculation with mycorrhizal fungi. Generally, foliar spraying of zinc sulfate + mycorrhiza increased the content of chlorophyll, sugar solvents and the relative water content of the leaf, caused the adjustment of the stress conditions and increased the resistance of the plant against drought, and by improving the quantitative and qualitative biochemical traits, it increased the economic yield of the St. John's wort plant.

Over the past few decades, human industrial activities have significantly reduced the blocking effect of the ozone layer in the stratosphere. As a consequence, there has been an increase in the penetration of ultraviolet (UV) radiation to the Earth's surface. This amplified exposure to UV rays poses a serious threat to living organisms, particularly plants. In our study, we investigated the impact of UV-A and UV-B radiation on some morpho-physiological traits as well as enzymatic and non-enzymatic antioxidants of rosemary (Rosmarinus officinalis L.). The study was conducted using a completely randomized design with three replications. UV radiation treatments were applied at three levels: control (no UV radiation), UV-A radiation, and UV-B radiation. The UV radiation was administered using broadband lamps manufactured by Q-Lab in the USA. These 40-watt lamps were employed for a duration of four hours per day. Our findings reveal that exposure to UV-B radiation resulted in a decrease in leaf dry weight, plant height, and the levels of chlorophyll a, b, and total chlorophyll by 29.57%, 13.44%, 17.7%, 33.77%, and 22.51%, respectively, compared to the control. Conversely, UV-B radiation led to an increase in the levels of non-enzymatic antioxidants such as carotenoids, phenols, and total flavonoids. Additionally, the activity of enzymatic antioxidants, including peroxidase, catalase, and ascorbate peroxidase enzymes, as well as the levels of proline and malondialdehyde, exhibited significant increases of 23.45%, 37.54%, 41.59%, 82.75%, 412.5%, 100%, 87.5%, and 359.32%, respectively, compared to the control. Regarding UV-A treatment, the levels of chlorophyll a, b, and total chlorophyll decreased. However, there was an increase in the levels of malondialdehyde, proline, and the activity of antioxidant enzymes catalase and peroxidase. Overall, the rosemary plants exposed to UV-B radiation exhibited higher quality in terms of medicinal and biological properties due to the increased presence of UV-absorbing compounds such as phenols, flavonoids, and carotenoids. However, it is worth noting that the yield of the plant decreased under UV-B treatment.

Heavy metals are part of the most important and dangerous environmental pollutants due to their long shelf life, non-degradability by soil microorganisms, and high potential for absorption by plants and entering the food chain. Cadmium is one of the toxic metals for organisms such as plants. The purpose of this research was to investigate the effect of cadmium on the ability of the common daisy plant. In this research, the effect of different amounts of cadmium (0, 10, 20 and 30 mgl-1) had done in a completely randomized design with three replicates. The results showed that the increase of the cadmium hadn’t any significant effect on common daisy plant fresh weight and length. Also, plant dry weight, shoot total chlorophyll, shoot and root carotenoids contents, total protein contents, plant translocation factor and bioaccumulation factor decreased with the increase of cadmium concentration, significantly. While shoot and root proline, and cadmium contents and catalase, peroxidase and ascorbate peroxidase activity increased, significantly. According to this research, the common daisy isn’t suitable for planting in studied cadmium concentrations.

In order to evaluate the inoculation of mycorrhizal and growth-promoting bacteria (Pseudomonas genus) on the tolerance of European borage to cadmium toxicity, a factorial experiment was performed in the form of a completely randomized design with 3 replications in the research greenhouse of the Agriculture Faculty of Yasouj University in 2019. The experimental factors include the application of biological fertilizer at 4 levels (control, application of mycorrhiza, application of growth-stimulating bacteria and combined application of mycorrhiza and bacteria) and 4 levels of cadmium concentration (0, 25, 50 and 75 mg cadmium per kg soil). The investigated traits were included root colonization percentage, plant cadmium content, some physiological characteristics and shoot dry weight of European borage. The results showed that with the increase in cadmium concentration, electrolyte leakage, proline content and cadmium content of aerial organs increased. The use of mycorrhiza and bacteria was evaluated positively compared to their non-use, so that in all four levels of cadmium, the highest proline, chlorophyll and relative water content, as well as the lowest electrolyte leakage and shoot cadmium concentration, were obtained from the combined two biofertilizers. Application of biofertilizer increased the dry weight of the aerial parts of inoculated plants compared to the control. The results showed that in the presence of 25 and 50 mg/kg of cadmium, the combined application of bio-fertilizers reduced 21% and 17% of cadmium transfer from roots to shoots of borage. Therefore, it is recommended to use biological fertilizers in areas contaminated with cadmium.

In this research, the effect of foliar spraying of brassinosteroid (0, 0.077 and 0.384 mg/liter) on grain yield and some physiological characteristics of wheat (Sirvan cultivar) under drought stress conditions (100% control) and 50% F.C.) was investigated in a factorial arrangement based on a randomized complete design with four replications at the research greenhouse of the Agriculture faculty, Shahid Bahonar University of Kerman on 2016. The results showed that drought stress caused a significant reduction in the biomass, yield and yield components of wheat and the decrease of these traits compared to the control was 31.7%, 29.6% and 20.3% respectively. On the other hand, brassinosteroid foliar spraying caused a significant increment of biomass, yield and yield components by approximately 22.7%, 22.4% and 12.5%, respectively, compared to the plants which were treated with distilled water under stress conditions. Drought stress had a significant effect on increasing of antioxidant enzymes activity (peroxidase, ascorbate peroxidase, catalase and superoxide dismutase) and the concentration of malondialdehyde, hydrogen peroxide, as well as the accumulation of carbohydrates and proline in wheat leaves. Spraying of brassinosteroid in both stress and non-stress conditions increased the activity of antioxidant enzymes and osmolytes accumulation (protein, carbohydrate and proline) and conversely reduced the amount of hydrogen peroxide and malondialdehyde, and this effect was more noticeable under drought stress condition. It seems that the effect of brassinosteroid application on modulating drought stress and improving wheat yield can be related to enhancement of osmotic regulation (through the accumulation of osmolytes) and increasing the activity of the antioxidant defense system mechanism in wheat.

In this study, the effects of drought stress and paclobutrazol on Anethum graveolans L. were investigated. The experiment was carried out as a factorial based on a completely randomized design with three replications in a greenhouse. Some growth and biochemical characteristics of dill under drought stress (irrigation-based) at three levels (30%, 50% and 70% field capacity) and paclobutrazol at two concentrations (20 and 40 mg/L) were investigated. Drought stress caused a significant reduction in the fresh and dry weight and length of both stem and root, as well as the contents of photosynthetic pigments and proteins, whereas this stress induced reduced sugar and proline content and catalase activity. Although fresh and dry weight and length of stem decreased in plants treated with paclobutrazol, paclobutrazol treatment significantly increased the root growth parameters and the contents of pigments and proteins in relation to drought stress and paclobutrazol treatment. In plants treated with paclobutrazol, the content of sugars, proline and catalase activity were significantly higher compared to non-treated plants and controls (P≤0/05). Moreover, the patterns of protein expression were different. SDS-PAGE analysis revealed a protein with a molecular weight of 11 KD under severe stress conditions and treatment with 40 mg/L paclobutrazol. This protein probably has a major role in dill resistance to drought and the stress amelioration effect of paclobutrazol.