جستجوی مقالات مرتبط با کلیدواژه « vitamin c » در نشریات گروه « منابع طبیعی »

Water shortage is an integral part of our current agriculture, and water stress is one of the most destructive environmental factors which adversely affects agricultural production worldwide. According to several studies, water deficit causes reduction of vegetative growth, leaf area, plant height, dry weight, photosynthesis rate, chlorophyll content, stomatal conductance, enzymatic activities, protein biosynthesis and amino acids accumulation in horticultural plants. Increasing reactive oxygen species (ROS) rate and activity is the one of most damaging effects of drought stress. Cucumber is a tropical crop with high water requirement. Wide leaves and shallow roots have made it a drought-sensitive crop. Based on reports, water deficit and drought stress can seriously affect yield performance and qualitative characteristics of cucumber. Measurements are needed in different aspects to overcome challenges associated with water deficit and water stress in cropping systems. So, in this study glycine amino acid were applied for its possible role under mild water shortage effects on cucumber growth characteristics.

In order to investigate the influence of glycine amino acid application on alleviation of negative effects of deficit irrigation, a greenhouse experiment was conducted based on completely randomized design with four replications. Treatments were assessed at six levels including 60 % FC, 70 % FC, 80 % FC, 60 % FC + glycine 500 mg plant-1, 70 % FC + glycine 500 mg plant-1 and 80 % FC + glycine 500 mg plant-1. Some of most important morphophysiological and biochemical characteristics of cucumber plants such as stem length, stem dry weight, leaf number, leaf area, internode length, growth period duration, fruit number, fruit set, vitamin C, chlorophyll index, total antioxidant, proline, catalase, peroxidase and polyphenol oxidase enzymes content were evaluated.

Result showed that deficit irrigation and glycine amino acid application significantly influenced morphophysiological and biochemical characteristics of cucumber plant. It was observed that vegetative traits including leaf number, leaf area index, stem length and dry weight, length of internode, growth period duration, chlorophyll index, and fruit characteristics including vitamin C content and fruit set were significantly reduced by deficit irrigation levels particularly at 60 % FC. The highest fruit number (86.5) was recorded under 70 % FC and application of glycine. In contrast, antioxidant capacity, proline, catalase, polyphenol oxidase and peroxidase enzymes content increased under 60 % FC. Glycine application could properly alleviate the negative effects of deficit irrigation on plant growth and yield. Studies have shown that glycine application maintains chlorophyll content and photosynthesis rate of plants under stress condition, which is mostly related to increasing stomatal conductance and carboxylation efficiency. Generally, water deficit reduces the yield performance of crops. And, this reduction could be correlated with decreasing leaf area and disruption of nutrients absorption. According to results of this study, maintaining the photosynthetic pigments caused by glycine application resulted in enhanced photosynthesis rate leading to higher yield comparing to control under deficit irrigation conditions.

Generally, the results of the current study demonstrated that deficit irrigation at level of 60 % FC caused induction of drought stress conditions. Induction of water deficit and drought stress higher than 70 % FC led to sever physiological and biochemical changes in cucumber plants resulting in considerable reduction of yield performance and qualitative characteristics. Water deficit increased proline content and antioxidant capacity (increasing the activity rate of antioxidant enzymes including catalase and peroxidase) of cucumber plants. Soil application of glycine amino acid alleviated the adverse effects of deficit irrigation. Because the highest fruit number was counted in 70 % FC + glycine 500 mg plant-1 treatment (with no significant difference with the control (80 % FC)), this treatment could be recommended to growers to save water consumption with no significant changes in yield performance comparing to control level.

Broccoli (Brassica oleracea) belong of the Brassicaceae family, contains high levels of bioactive compounds, such as vitamin C, phenolic compounds, and glucosinolates. These nutrients have antimicrobial, antioxidant and anti-cancer properties. However, broccoli can usually be stored for several days during transport or at the time of sale in the store or after purchase by consumers. During this period, their flowers start to turn yellow and their nutritional content decreases rapidly. In order to delay the aging stage in broccoli, various methods such as changing the atmosphere of the storage place, irradiating red light, the effect of plant hormones and treating chemical compounds can be used to maintain the appearance quality of broccoli and delay the aging stage. Various chemical compounds have been used to delay the aging stage in broccoli, but choosing a compound that has the least harmful effect on human health is one of the main priorities of scientists active in this field. One of these chemical compounds that has the least negative effects on health is melatonin. The purpose of this study is to investigate the effect of melatonin treatment on physiology after harvesting broccoli during storage.

In a primary experiment, broccoli was treated with 10, 25, 50, 100, 250, 400 and 600 μmol/L melatonin. Primary test results showed that 100 μmol/L melatonin had a significant effect on post-harvest appearance quality. Therefore, the 100 μmol/L melatonin treatment was used as a reference for more extensive studies in this paper. In this study a factorial experiment was conducted using a randomized completely design with three replication. Broccoli was divided into control and treatment groups, and after 20 minutes immersion in 100 µmol L-1 as treatment and distilled water as control. Then it was kept at a temperature of 4±1 °C for 4 weeks. In this research, the indicators of weight loss percentage, content of photosynthetic pigments, the activity level of antioxidant enzymes, the content of free radicals, and the amount of phenolic, flavonoid, vitamin C, and glucosinolate in weeks 0, 1, 2, 3 and 4 were evaluated after storage and with three repetitions.

The results of this research showed that broccoli treatment with melatonin was more effective in maintaining fresh weight during storage than the control. In the first to fourth weeks, the percentage of weight loss in the control group was 1.26, 1.57, 2.19 and 2.23 times higher than the melatonin-treated group, respectively. The results indicated that there was a significant difference (p<0.05) in the content of chlorophyll a and b in different weeks of storage between the control and the melatonin-treated groups. The melatonin treatment can increase the content of chlorophyll a, b and total chlorophyll by suppressing the activity of chlorophyllase enzyme. So that, melatonin treatment led to a decrease in chlorophyllase enzyme activity, and this decrease in the fourth week in the melatonin-treated group was about 47.8% less than the control group. The results indicated that there was a significant difference (p<0.05) in the content of vitamin C and glucosinolate between control and the melatonin-treated groups in during storage. Compared with control group, significantly higher total phenolic content was observed in the melatonin treated group in during of storage. Comparison of means showed that the content of flavonoids in broccoli treated with melatonin showed a general increasing trend, so that in the fourth week, the content of flavonoids in the treatment group was 3.67 times that of the control group. Measuring the activity of antioxidant enzymes showed that melatonin treatment was able to reduce the content of superoxide free radicals by increasing the activity of superoxide dismutase enzyme, so that in the group treated with melatonin, SOD activity increased by 35% and 47.6% in the third and fourth weeks, respectively.

In general, the effect of melatonin on broccoli is associated with increasing the activity of antioxidant enzymes and suppressing the activity of chlorophyll-degrading enzymes, which reduced the content of reactive oxygen species and increased the content of chlorophyll. Based on the data obtained in the present study, as a result of the increase in phenolic and flavonoid compounds, antioxidant enzymes and also antioxidant compounds such as vitamin C and glucosinolate, it improves the quality of broccoli. Generally, it seems that postharvest treatment with melatonin can be a useful method to maintain the appearance as well as the quality and nutrient levels of stored broccoli and increase its useful life.

Due to the increasing demand for organic products, the use of growth-promoting bacteria, which play an important role in the sustainability of agricultural ecosystems, has been considered for the last two decades, and there are limited studies to determine the best efficiency of their consumption method. Accordingly, this study was conducted to investigate the most effective method of application biofertilizers on morph physiological, biochemical and yield traits of Tomato plants in greenhouse conditions.

In order to investigate the effect of consumption method and type of biofertilizers on morphophysiological, biochemical and yield traits of Tomato, a factorial experiment was conducted in a completely randomized design in the Research Greenhouse Khorasan Razavi Agricultural and Natural Resources Research and Education center in 2020. The first factor was three methods of application (seed inoculation with foliar feeding, foliar feeding and soil consumpation and the second factor was types of biofertilizer (control, nitroxin, biophosphate, fertile potassium and a mixture of nitroxin and biophosphorus (rate 1:1).

Analysis of some physical and chemical properties of soil at the beginning and end of the experiment showed that the application of biofertilizers without the use of any chemical fertilizers improved soil fertility and high availability of macronutrient, which showed an improvement in soil health indices. The soil texture remained constant at the end of the experiment but the soil saturation percentage was increased which indicated an increase in the volume of water in the soil compared to the volume of pores during the test period. Almost all properties were better condition at the end of the experiment than at the beginning, including electrical conductivity and soil acidity, which decreased by about 0.5 and 0.3 units, respectively. The results showed that the maximum plant height (176 cm) was obtained by using a mixture of nitroxin and biophosphorus from soil application. The lowest dry plant weight (23.7 g) was recorded from non-use of biofertilizers and the use of a mixture of nitroxin and biophosphorus produced about 52% more dry weight of the plant in compare of control. The application of biofertilizers had a significant effect on increase dry weight of root, so that the root dry weight was increased about 53% in compare of control by using mixture of nitroxin and biophosphorus. In the soil application method with the application of all biofertilizers, the number of fruits per plant was more than 137, the highest of it (145) was obtained from a mixture of nitroxin and biophosphorus. The highest fruit weight per plant (449 g plant-1) was obtained from the application of a mixture of nitroxin and biophosphorus in soil application. The highest amount of photosynthesis (18.2 μmol CO2 m-2s-1) and stomatal conductance (20.0 mmol CO2 m-2s-1) were obtained from the effect of combined nitroxin and biophosphorus fertilizer on seed inoculation and foliar feeding. The highest amount of lycopene (7.69 mg 100-1g FW) and the amount of vitamin C (57.7 mg 100-1g FW) were obtained from the soil consumption of nitroxin biofertilizer.

Increasing diversity in soil microorganisms leads to increased soil fertility. In soil application method, the metabolic activities of bacteria are improved due to the availability of suitable temperature, oxidation and reduction conditions, minerals, organic carbon as a source of energy and water, which leads to the release of nutrients from organic materials. The results showed that due to the high growth of bacteria in the presence of different substrates in the soil and the high surface-to-volume ratio in them, the use of biological fertilizers as soil application was increase morphological and physiological characteristics, yield traits of Tomato plant.

In this study, the effects of freeze and hot air dryings on aroma, vitamin C content and color change of orange slices were studied. The freeze dryer was drying at -50 °C and the hot air dryer at 60 °C. The results showed that the freeze dryer maintained the color quality and aroma of the dried slices similar to the fresh orange slices (fresh oranges L*=48.79, a*=-3.17 and b*=44.25 and freeze dried L*=82.26, a*=-2.71 and b*=50.68) but in the case of hot air dryer, the color quality decreased and browning was occurred (L*=58.09, a*=10.78 and b*=45.51). The highest response of olfactory sensors in fresh orange, freeze dried and hot air dried slices were MQ9, MQ7, and MQ3, respectively, and the lowest response of olfactory sensors in all three slices was MQ6. The biggest difference between the sensors' response was the change in the product's aroma during drying process. The amount of vitamin C in two methods of freezer drying (902.4 mg / 100g) and hot air drying (956.6 mg / 100g) decreased compared to fresh orange slices (1001.3mg / 100g). According to the measured Vitamin C contents, in hot air dried slices the concentration of Vitamin C was higher than that for freeze dried slices.

In order to study the effects of calcium and light duration on growth and quality of lettuce, this experiment was conducted as split plot based on the randomized complete design with three replications, in research greenhouse of University of Zanjan during 2020. The main plot consisted of light treatments at two levels included natural light duration (an average 7000-8000 lux) and natural light in addition four hourse complementary light (600 lux) and the subplot was consisted of three levels of calcium lactate (0.5, 1 and 1.5 g L-1(, calcium chlorid (3, 6 and 9 g L-1) and distilled water as a control. The results showed that increasing light duration significantly increased leaves number, plant fresh weight, total chlorophyll, phenols and flavonoids, vitamin C and anthocyanin contents. Application of calcium chlorid (6 and 9 g L-1) and calcium lactate (1.5 g L-1 ( increased plant fresh weight (10.3, 10.5 and 11.6 g) and Ca concentration of internal leaves (12.8, 12.9 and 12.2%) lettuce, and inhibiet tip burn disorder in lettuce lives. The highest tip burn leaf number (3.5) was observed in plants whitout Ca teated under complementary ligh treatment. Also the highest amount of plant fresh weight, anthocyanin, total phenol and flavonoids and antioxidant capacity was obtained by using calcium lactate 1.5 and calcium chloride 3 and 6 g L-1 with increasing light duration. According to the results, application of calcium lactate 1.5 g L-1 and calcium chlorid 6 and 9 g L-1 with increasing light duration can be preposed to improve growth and quality of lettuce.

In the present study, the biochemical and morphological differences of fruit in eight cultivars of mandarin (Orlando Tangelo, Wakiva, Dansi, Honey, Kara, Wilking, Farichid, and Ferement) were investigated. Also, antioxidant capacity and chlorophyll and carotenoid pigments of the juice were evaluated in six cultivars (Orlando Tangelo, Wakiva, Dansi, Honey, Kara and Wilking). The experiment was conducted in a completely randomized block design with three replications. The results showed that the different cultivars had significantly different characteristics. Wakiva cultivar had the highest content of vitamin C, antioxidant capacity, flavor index, pH, and skin thickness and lowest titrable acidity among other cultivars. The highest total soluble solids content belonged to Wheeling cultivar, which wasn’t significantly different with Wakiva cultivar. Kara cultivar had the highest weight, diameter, length, and volume, while Ferement cultivar had the best shape index among other cultivars. In addition, Wakiva cultivar had the best nutritional quality due to higher vitamin C (117.04 mg ascorbic acid per 100 ml juice), antioxidant capacity (45.62%) and flavor index, and was the best for transportation and handling due to peel thickness. Vitamin C content in Wakiva was 82.46% more than Hani cultivar. Kara and Ferment cultivars, having larger and wider fruits, respectively, had better overall quality and were more marketable than other cultivars. Although Hani cultivar due to smallest fruits and lowest vitamin c had a lower marketability and edible quality, but due to having the highest carotenoid pigments, it had higher juice quality and may be recommended for processing in the juice industry.

Pomegranate (Punica granatum L.) is one of the oldest edible fruits with high variability and is native to Iran. This research was conducted to evaluate the morphological and biochemical characteristics of eight local pomegranate cultivars including Aliakbari, Gar, Post ghermez, Golabi, Sorahi, Mirzaei, Yazdani and Lopsorkhi grown in Najaf-Abad region of Isfahan. Pomegranate fruits were harvested at full maturity stage and the considered traits were measured according to standard methods. Among the studied cultivars, the Post ghermez cultivar had the highest 100 aril (45.2 g) fresh weight. The highest fruit peel thickness (4.71 mm) was measured in Gar cultivar. Aliakbari cultivar had the highest amount of total anthocyanin content (1.41 mg/100 g), total phenolic content (58.56 mg/100 g) and titratable acidity (1.06 mg/100 g). The highest phenotypic variation was seen in harvest index, and Lopsorkhi and Aliakbari cultivars had the highest and lowest values for this trait, respectively. Overall, Aliakbari and Sorahi cultivars due to the highest favorable traits can be introduced as the elite cultivars.

In order to investigate the effect of glycine- betaine (GB) and intermittent warming (IW). On shelf life and quality of sweet pepper fruits an experiment was conducted as a factorial based on complete randomized design in University of Zanjan in 2016. Treatments were consisted of intermittent warming at three levels (control, 20 and 30 ºC) and glycine- betaine at three levels (0, 5 and 10 mM). The fruits were stored at 4 °C and 85±5% RH for 30 days. The results showed that the amount of vitamin C, chlorophyll, carotenoids content and peroxidase activity in the fruits were decreased and fruit weight loss percentages, extract pH and electrolyte leakage were increased during storage at low temperature (4 °C) by gradually increasing of storage time. Intermittent warming and glycine betaine had positive effects on studied traits such as soluble solids, extract pH, vitamin C, chlorophyll, carotenoids content and peroxidase activity and improved the quality of pepper fruit during storage at low temperatures. These treatments prevented weight loss and electrolyte leakage during the storage. The intermittent warming between temperatures of 20 °C and 5 mM of GB were found to be more beneficial in improving the qualitative characteristics of pepper fruits. Therefore, the use of glycine betaine and intermittent warming can increase quality of sweet pepper, and by preventing the increase of contamination, can be improved the shelf life of sweet pepper.

In order to study the effects of foliar application of naphthalene acetic acid (NAA) on growth, yield and fruit quality of sweet pepper "California Wonder", an experiment was conducted in a randomized complete block design with three replications in the Research field of Faculty of Agriculture (University of Zanjan, Iran) in 2016. Treatments were consisted of NAA at five levels of 0 (control), 50, 100, 150 and 200 mg.L-1. The results showed that foliar application of NAA had significant effects on vegetative traits, yield and its components, and fruit quality. The highest fruit number per plant (5.6 and 6) and yield (24.6 and 24.9 t.ha-1) was achieved at 50 and 100 mg.L-1 NAA. The maximum plant height and chlorophyll index were obtained by application of 100 and 150 mg.L-1 NAA. The highest amount of total soluble solid (4.93 °B), vitamin C (103.73 mg.100ml-1) and fruit firmness was recorded at 100 mg.L-1 NAA. According to the results, application of 100 mg.L-1 NAA can be proposed to improve yield and fruit quality of sweet pepper.

In order to investigate the effects of humic acid concentration on quality indices of Kiwifruit cv. Hyward, an experiment based on complete block design with 4 replication was conducted during 2015-2016 in one of the Kiwifruit garden of Talesh city, Gilan province. Experimental treatments included soil drenching method and foliar spraying of different levels (control, 2, 4 and 6 Kg/h) of humic acid. In this study, some traits such as weight of fruit, yield, firmness, soluble solids, titratable acidity and vitamin C, pH of fruit juice and total phenol of fruit were measured. Results of ANOVA showed that different concentration of humic acid had significant effect on weight of fruit, yield, soluble solids, and vitamin C traits at 1% probability level and these treatments had significant effect on titratable acid it/at 5% probability level. However, the use of humic acid did not has significant effect on fruit firmness, total phenol and pH of fruit juice. Comparison of means showed that the leaf application of 4, 2 and 6 kg.ha-1 concentration from humic acid had the highest fruit weight and yield. The best result for soluble solids and titratable acidity was obtained from Humic acid at concentration of 4 kg.ha-1 with soil application. Also, the highest amount of vitamin C was recorded from leaf application of 4 kg.ha-1 of humic acid. In general, results showed that the leaf application of 4 kg. ha-1 of humic acid, was more effective in the most studied traits. The highest yield (61.65 kg per tree), fruit weight (145 g), soluble solids (5.57.5 Brix), and vitamin C (38 mg/ 100g Fresh weight) were obtained from the above treatment.

A 36-day rearing trial was conducted to examine the enrichment of Artemia fransiscana nauplii with fatty acid and C (Ascorbyl-6-palmitate) on growth performance, survival and stress resistance of yellowfin seabream, Acanthopagrus latus larvae. Yellowfin seabream larvae at the first exogenous feeding with 53±0.01 mg body weight and 0.84±0.08 mm length were randomly distributed into 5 treatments and three replicate were assigned to each diet. The test treatments were as follows: larvae fed Cod liver oil + 5 %, 10 % and 15 % (w/w) vitamin C enriched Artemia nauplii (C1, C2 and C3 groups, respectively); larvae fed fatty acid without vitamin (HUFA group) and non-enriched Artemia (control). All treatments fed Rotifer for 5 days and then fed non-enriched Artemia for 10 days after first feeding and then fed enriched Artemia and commercial artificial feed for 21 days. At day 36, submersion in salt water (0 ppt for 2 hours) and cold water (15 ºC for 2 hours) was performed to evaluate larvae resistance to salinity and temperature stress. Growth parameters were analyzed at the end of the experiment. The highest growth was found in control group at the end of the experimental trial, but growth factors were not significantly different between groups (P<0.05). Survival was significantly different between control and other group from day 17 that fed enriched Artemia (P<0.05). Stress tolerance was not significantly different at 0 ppt and 15ºC. There was no comparable different in cortisol, total protein and glucose under stress conditions (P<0.05). These results indicated that the enrichment of Artemia with essential fatty acids and vitamins C can affect survival in Yellowfin seabream Acanthopagrus latus larvae.