guaiacol peroxidase

Investigating the possibility of resistance to Fusarium Basal Rot in Azarshahr red onion cultivar using MelatoninAbstractAn experiment was carried out using 0, 50, 100 and 300 μM melatonin in onion cultivar to investigate its effect on induction of resistance to Fusarium basal rot caused by Fusariumoxysporum f. sp. cepae. In this experiment, traits such as total phenolic content, hydrogen peroxide, malondialdehyde, antioxidant enzymes (catalase (CAT) and guaiacol peroxidase (GPX)) and disease-related enzymes (phenylalanine ammonia-lyase (PAL), chitinase and β-1,4-glucanase) were measured. The results showed an application of exogenous melatonin caused an increase in the total phenolic content and activity of antioxidants and disease-related enzymes, resulting a decrease malondialdehyde (MDA) and in the hydrogen peroxide (H2O2) level in Fusarium-treated plants. Although all concentrations of melatonin altered some biochemical and physiological traits in onions under Fusarium basal rot stress, the best overall result regarding induction of resistance to Fusariumoxysporum f. sp. cepae in these plants was observed on days 12 and 16 by applying 100 μM melatonin.

Fennel is a medicinal plant; all of its parts were being used by humans in different ways. This plant is relatively sensitive to salinity. A factorial experiment as a randomized complete block design with three replications at the greenhouse level was executed to investigate the effect of vermicompost on the increase of salinity tolerance in four fennel populations (Mashhad, Urmia, Shiraz, and Bushehr) in the vegetative stage of the plant, emphasizing the evaluation of some osmotic and antioxidant protection indicators. Experimental treatments were designed with four levels of salinity (0, 40, 80, and 120 mM of NaCl) and two levels of vermicompost (0 and 5% v/v). After harvesting, the roots were separated from the stem to analyze the biochemical variables. Salt stress caused a decrease in the total soluble sugar and starch content in the shoot and an increase of those in the root of the studied populations. In addition, under stress conditions, the proline content of shoot and root, total free amino acid, total phenol, and activity of guaiacol peroxidase and catalase were increased in fennel populations, while total soluble protein and anthocyanin content were decreased. Vermicompost treatment increased the content of soluble carbohydrates, soluble protein, free amino acids, proline, total phenol, and anthocyanin, and decreased the activity of guaiacol peroxidase in the shoot, as well as the starch content in the roots of fennel populations under non-stressed and stressed conditions. Despite observing the complexity in the changes of the analyzed indicators which were dependent on the type of population and the dose of stress, our results showed that the application of vermicompost with a concentration of 5% can improve the osmotic and antioxidant protection in the studied populations of fennel under salinity stress.

Drought is one of the most serious threats in agricultural production worldwide, and climate change is likely to exacerbate this threat. In order to evaluate the drought tolerance of different castor ecotypes, a factorial experiment was conducted in a completely randomized design with three replications in Sari Agricultural Sciences and Natural Resources University. The first factor was 22 castor ecotypes and the second factor was drought stress with 5 levels, full irrigation, four levels (irrigation was cuted at the primary of spike growth) (11, 22, 33, 44 days after Irrigation cut off). Experimental traits were included the activity of the antioxidant enzymes Catalase, Guaiacol peroxidase and Ascorbate peroxidase, the biochemical activity of Malondialdehyde (MDA), Proline content, Plant height, stem diameter and number of leaves. Cluster analysis classified the ecotypes into three clusters under normal and drought stress conditions.The results showed that the activity of Catalase, Ascorbate peroxidase, Guaiacol peroxidase, Malondialdehyde and Proline content under drought stress conditions of the third group (Tolerant) compared to the first group (Sensitive) were increased 81.5, 81.87, 70.27, 80.05, 81.87, respectively. On the other hand, the differences between tolerant and sensitive groups at stress conditions in plant height, stem diameter and number of leaves were 74.74, 80.50 and 83.38%, respectively. The highest correlation under drought stress conditions was observed between Catalase and Ascorbate peroxidase (r = 0.997) and the lowest non-significant correlation was observed between proline and plant height (r = 0.292). According to the results, in terms of the studied traits 5 and 19 ecotypes were introduced as drought tolerant ecotypes.

This research was carried out at the experimental farm of the Darab Agricultural and Natural Resources College of Shiraz University during 2017-2018 growing season. A split factorial experiment was layout based on a randomized complete block design with three replicates. Treatments included two irrigation levels as the main plots [1. Normal (IRN): irrigation based on the plant's water requirement up to the physiological maturity and 2. Irrigation with water stress (IRws): irrigation based on the plant's water requirement up to the anthesis stage (cutting of irrigation after anthesis)]. Also, sub plots were two levels of plant residues [1. without residue, 2. with residue: returning 30% of wheat residues to soil] and four nitrogen (N) fertilizer sources [N0, no nitrogen fertilizer (control); N100, 100 kg N ha-1; Bio + N50, Biofertilizer (Azospirillum brasilense) + 50 kg N ha-1 and Bio, Biofertilizer (Azospirillum brasilense)]. Results showed that the interaction effect of residue × N fertilizer source on chlorophylla, carotenoid, catalase and guaiacol peroxidase enzymes traits was significant. The N100 and Bio + N50 treatments significantly increased these traits compared to N0 in without residue conditions. In contrast, in the presence of residue, there was a similar trend to without residue conditions, however, the reaction of these traits to N100 and Bio + N50 supply were much more severe. The interaction of irrigation regime × N fertilizer source on catalase and guaiacol peroxidase enzymes showed that the N fertilizer application increased the amount of these enzymes, regardless of the N source, in IRN conditions. Similarly, in IRws conditions, the catalase and guaiacol peroxidase enzymes levels improved by N fertilizer supply as compared with N0, however, the intensity of their reactions to N application, especially, N100 and Bio + N50 were much more than the normal moisture conditions. The highest grain yield was achieved by Bio + N50 under IRN and IRws conditions. In general, with respect to superiority of combine N fertilizer (Bio + N50) in biochemical and grain yield traits in normal and water stress conditions and economic and environmental considerations as well, this N fertilizer regime is recommended for water availability restriction conditions in Southern regions of Iran.

The aim of this study was to investigate the effects of inoculation of two species of mycorrhizal fungi on growth, colonization percentage, antioxidant enzymes activity, health and risk index of coriander under cadmium stress.

A pot experiment was conducted in a completely randomized design with 2 factors and 3 replications in the research greenhouse of the Department of Horticultural Science and Landscape Engineering at the Ferdowsi University of Mashhad in 2018. The first factor was cadmium nitrate at 4 levels of 0, 20, 40, and 80 mg kg-1 soil and the second factor was mycorrhiza application at 3 levels of non-inoculation, inoculation with Glomus mosseae and Glomus intraradices.

The results showed that with increasing cadmium concentration in the soil, the shoot and total biomass of plant, leaf area, number of seeds, 1000 seeds weight, colonization percentage, soluble protein, catalase, ascorbate peroxidase, guaiacol peroxidase, and polyphenol oxidase activities were significantly decreased in coriander. But malondialdehyde content, health and risk index increased. However, the use of mycorrhizal fungi reduced the harmful effects of cadmium in the plant. This resulted in a decrease of 47.1% of the risk and health index and 17.2% of malondialdehyde in the plant.

According to the findings, use of mycorrhizal fungi had a significant effect on the improving of harmful effects of cadmium in coriander, thus improved the risk and health index for consumers. Therefore, using mycorrhizal fungi as a management strategy in polluted areas with this heavy metal is

Salt stress is one of the most important abiotic stresses which severly affects agriculture in the world. One of the strategies to deal with this stress is to investigate the mechanisms of tolerance in halophyte plants and to use them for crop improvement. The halophyte plant “Aleuropus littoralis” can tolerate salinity levels up to 600 mM. In this study, in order to investigate the mechanism of the antioxidant response of this plant to salinity stress, one-month seedlings were irrigated with Hoagland solution containing 0, 200 and 400 mM NaCl to induce salt stress. After 72 hours, root, stem and leaf tissues were sampled and the response of each tissue to salinity stress was evaluated. The results were compared using Duncan's multiple range test (p<0.05) after ANOVA. With increasing level of stress, protein content in all three tissues increased significantly. The amount of H2O2 in stem and root decreased with increasing salt concentration, but increased at 200 mM salt concentration. Based on the results, the general pattern of change in the activity of antioxidant enzymes was different in response to salt stress. The activity of superoxide dismutase in all studied tissues increased significantly with increasing stress level, so that the highest activity of the enzyme was observed in stem tissue and at 400 mM salt concentration (3.7 times more than the control). However, the changes in the activity of catalase and guaiacol peroxidase showed a decreasing trend or no significant change, so that the catalase activity in the leaf and at 400 mM salt concentration was almost half of the control and in the root more than half of the control. Finally, with increasing levels of stress, significant increase in ascorbate peroxidase activity was observed in all treatments, except in root tissue and 200 mM salt concentration. In general, according to the results, it can be stated that the balance between the antioxidant defense indices leads to the maintenance of destructive molecules such as H2O2 at a minimal level and plays an effective role in salinity stress tolerance in the A. littoralis.

The fig, a sub-tropical crop, consumes as a table fruit as well as a dry product. Since, salinity is the serious concern of fig production, during 2016-2018, seven fig cultivars (‘Sabzʼ, ‘Siyahʼ, ‘Shah Anjirʼ, ‘Atabakiʼ, ‘Kashkiʼ, ‘Matiʼ and ‘Barʼ) were subjected to saline water (0.5, 2, 4, 6, 8 and 10 dSm-1). Then, potein, proline, photosynthetic pigments, superoxide dismutase, catalase, guaiacol peroxidase and ascorbate peroxidase content were compared to introduce the most salt-tolerant cultivar. The results indicated, salinity caused an increase in total protein, proline and activity of antioxidant enzymes, but a decrease in chlorophyll (a, b, total) and carotenoids pigments. According to the results “Siyah” and “Sabz” cultivars were the most salt-tolerant and “Shah Anjir” was the most salt -sensitive cultivar. The ‘Atabakiʼ, ‘Kashkiʼ, ‘Matiʼ and ‘Bar anjirʼ were placed between them

In order to improve plant growth of Niger )Guizotia abyssinica (L.F) Cass( under drought stress, an experiment was conducted on its seeds as factorial in a completely randomized design with three replications at the research greenhouse of Shahrekord University in 2015. The first factor was different magnetic field intensities including: 0, 50, 100, 150 and 200 mT (in 5 minutes period of time) as physically pre-treatment and the second factor was drought stress (2, 4 and 6 day irrigation intervals). The results showed that the effect of the interaction effects of different levels of magnetic field intensity and drought stress were significant on all of the evaluated characteristics. The minimum membrane electrolyte leakage and the maximum ascorbate peroxidase and guaiacol peroxidase enzymes activity and relative water content in 200 mT field intensity under 2 days irrigation intervals, the maximum catalase activity in 100 mT field intensity under 4 days irrigation intervals, the maximum leaf dry weight and root volume in 100 mT field intensity under 2 days irrigation intervals and the maximum flower and root dry weight in 150 mT field intensity under 2 days irrigation intervals were observed. The most evaluated traits showed decreasing trend by increasing irrigation intervals in different magnetic field intensities. Generally, 150 and 200 mT fields intensity for 2 days irrigation intervals, 100 and 150 mT fields intensity for 4 days irrigation intervals, 100 and 200 mT fields intensity for 6 days irrigation intervals were the most effective intensities for improving and increasing the performance of characteristics under drought stress conditions.

The aim of this study is to evaluate the interaction effect of salinity stress and superabsorbent polymers on physiological traits of basil. A pot experiment was conducted as factorial based on a completely randomized design with four levels of salinity (0, 40, 80 and 120 mM NaCl in irrigation water) and four levels of superabsorbent polymers included (control, Ackoasorb, Stockosorb and Terracottem). The measured traits were soluble protein, antioxidant enzyme activities, malondialdehyde content and essential oil production. Antioxidant enzyme activities of catalase, guaiacol peroxidase, ascorbate peroxidase and polyphenol oxidase at first harvesting and high salinity (120 mM) under Ackoasorb, Terracottem, Terracottem and Ackoasorb usage decreased 52.68, 73.1, 68.07 and 75.35%, respectively, and also at second harvest at highest salinity level (80 mM) the activity of these enzymes under Ackoasorb, Terracottem, Ackoasorb, Terracottem and Terracottem decreased 37.6, 62.5, 46.38 43.06 and 38.47%, respectively.  With increasing salinity the essential oil production decreased and Tracheotem superabsorbent increase it. At first harvesting, a significant positive correlation was observed between malondialdehyde with guaiacol peroxidase (r = 0.751) and at second harvesting ascorbate peroxidase with protein (r = - 0.753) had a significant negative correlations, moreover, significant positive correlations were found between superoxide dismutase with guaiacol peroxidase (r = 0.848), malondialdehyde with guaiacol peroxidase (r = 0.789) and malondialdehyde with ascorbate peroxidase (r = 0.743). The results showed that application of superabsorbents under salinity stress conditions could decrease the severity of this stress and thereby cause to decrease the antioxidant enzyme activities and malondialdehyde amount significantly, but increased the soluble protein and essential oil content.

Datura stramonium as a well-known medicinal plant is rich in tropane alkaloids such as hyoscyamine and scopolamine and currently the vast majority of the studies have been focused on optimization of production conditions of these valuable materials in the world. In this research, the effect of sucrose (15, 30 and 45 g/L) as an abiotic elicitor was investigated on fresh weight (FW), hyoscyamine and scopolamine production, protein content, activity of catalase (CAT) and guaiacol peroxidase (GPX) of D. stramonium. The amount of hyoscumine and scopolamine were measured by high-performance liquid chromatography (HPLC) and spectrophotometery method was applied for studying of total protrin content and activity of CAT and GPX. According to the results, the highest amount of fresh weight (0.82 g), production of hyoscyamine (5 mg/g FW), scopolamine (20 mg/g FW) and CAT activity (0.5 U/mg protein) were recorded on the root of 45 g/L-treated plantlets but the highest amount of protein (0.24 mg/g FW) was observed on shoot of 30 g/L ones. In addition, the maximum GPX activity was determined on root of plantlests treated with 30 g/L sucrose (1.52 U/mg protein). In conclude, the concentration of 45 g/L of sucrose can be a good elicitor to increase production of hyoscyamine and scopolamine with high medicinal value in D. stramonium which probably due to the fact that sucrose does not only act as a carbon and energy source but also induces signaling pathway of tropane alkaloids synthesis.

This study was conducted to evaluate the response of germination, seedling growth and antioxidant enzymes activity 15 chickpea cultivars to salinity at the University of South Korea Dankook a factorial experiment in a randomized complete block design with four replications. The treatments include chickpea cultivars and, salinity levels of water (water with electrical conductivity 0.7 dS/m as a witness and as salinity salinity level 5 dS/m), respectively. The results showed that salt stress decreased seed germination and enzyme activity of alpha amylase was on the soil surface. Salinity reduced leaf dry weight and photosynthesis chickpea varieties of chickpea cultivars, but increased respiration rate. Cultivars of MCC873, MCC10, MCC78, MCC870, MCC537 and MCC392 highest leaf dry weight and photosynthesis, respectively, and at the same time cultivars MCC776 and MCC552 with 6.10 g dry weight and plant 0.63 from a low dry weight respectively. Activity of catalase and glutathione peroxidase guaiacol was increased by salinity. The highest concentrations of malondialdehyde, indicating that the degradation of plant cell membranes in the cultivars of MCC759, MCC361 and MCC101 of 0.95, 0.94 and 0.92 nmol per gram fresh weight of seedlings were observed. MCC392 while the lowest concentrations of malondialdehyde was under salt stress. The results showed that under salinity stress cultivars of MCC 873, MCC 10, MCC78, MCC870, MCC537 and MCC392 with enzyme activity were more antioxidants had higher rates of photosynthesis and plant weight.

Cadmium is regarded as one of the most toxic elements for living organisms that plays no positive biological role. In order to study the effect of cadmium heavy metal on growth factors of Carthamus tinctorius, an experiment was conducted in a completely randomized design with three replications in open-air conditions. Different levels of cadmium sulphate applied to the pots in the experiment were 150, 300, 450, 600, 750, 900, and 1000 µM solutions. Based on the results of the present study, the dry weights of roots and shoots significantly decreased in response to varying levels of cadmium but shoot lengths and relative growth rates were not significantly different compared to control. The results of the analysis of variance showed that the amount of chlorophyll a,b and total chlorophyll significantly decreased compared with the control while the decrease in carotenoid compounds content and relative water content in Carthamus tinctorius with increasing cadmium concentration was not significantly different comparing with the control. The amount of soluble sugars in the roots and shoots of Carthamus tinctorius plants treated with cadmium increased, but the amount of insoluble sugars in the aforementioned organs decreased. The results of the analysis of variance also revealed that with increasing the concentration of cadmium, the cadmium levels of shoots increased. Findings also showed that with the increase in cadmium concentration at some levels (300, 750, 900, and 1000 µM) the activity of guaiacol peroxidase enzyme showed no significant difference compared to control. In addition, the amount of polyphenol oxidase enzyme increased which was significant at all levels comparing to control and only at 150 µM level no significant difference was observed compared to control. The results of this research showed that safflower is able to absorb cadmium in its tissues and it can be used for phytoremediation of cadmium heavy metal.

Aim: Iran is considered as an arid and semi-arid area of the world and also it is one of the main countries producing cucumbers; so study the effects of drought on this plant and also its antioxidant system changes are important.
Material and In this study, cucumber cv. Isfahani plants were grown under greenhouse condition. In order to study the effect of changes in protein and antioxidant systems, cucumber plants at 3 to 5 leaf stage were treated with 4 levels of drought stress (100, 75, 50 and 25 percent) and their responses to applied stresses were investigated. The amounts of electrolyte leakage, lipid peroxidation, protein, proline, total antioxidant, catalase and guaiacol peroxidase activities, α-tocopherol and hydrogen peroxide were measured.
The results study showed that the contents of electrolyte leakage, lipid peroxidation, proline, total antioxidant, catalase, guaiacol peroxidase, α-tocopherol and hydrogen peroxide increased under drought stresses as compared to the control plants. However, protein index decreased under drought stresses in comparison with controls.
The obtained findings showed that in this cultivar of cucumber tolerance to drought was related to enzymatic and non-enzymatic antioxidant activities and also proline accumulation.

The chilling stress during seed germination of most plants cause disorder in many phisiological processes, prevention of radicle exit and decrease germination percentage. So, the effect of different seed priming treatments on seed germination parameters changes of annual medic plant under chilling stress was evaluated as a factorial experiment in completely randomized design with four replications. Treatments were consisted of different primings (hydropriming, halopriming, osmopriming and no priming) and five levels of temperature (3, 6, 9, 12 and 15 ˚C). Results showed that reduction of temperature caused linearly reduction of germination rate in seeds treated with hydroprime and osmoprime, but halopriming treatment was improvement germination percentage under chilling stress. The maximum radicle weight was observed in hydropriming treatment. Reducing of temperature increased amount of proline in all priming treatments. Moreover, osmopriming treatment caused increase activity of catalase and guaiacol peroxidase enzymes at temperature of 3˚C. In conclusion, hydropriming treatment is suitable for germination rate and percentage improvement and better establishment of annual medic plant under chilling stress conditions that this can appropriate for increase the exposure potential of this plant as green manure in cold and mild regions of the country.