جستجوی مقالات مرتبط با کلیدواژه "ویتامین ث" در نشریات گروه "کشاورزی"

The Nirvin variety is one of Iran's most cultivated varieties of bell peppers. Still, no specific dietary and irrigation program has been determined to achieve the maximum yield and water use efficiency. To determine the optimal irrigation for greenhouse cultivation of this variety, an experiment was conducted in a completely randomized design with three replications based on irrigation treatments of 100 (I0), 85 (I1) and 70 (I2)% water requirement in the research greenhouse of the Faculty of Agricultural Sciences, University of Guilan in 2022-2023. The results showed no significant difference in final yield traits and water use efficiency between the 100 and 85% water requirement, with the reduction of irrigation to 70% water requirement, these traits decreased by 21.43, and 8.52%, respectively. The results related to the amount of ionic leakage and free proline content indicated that reducing the irrigation to 85% of the water requirement did not cause water stress in the plant. The reduction of irrigation led to an increase in the length of the fruit stems and a decrease in their thickness. The highest number of fruit lobes was observed at the 85% water requirement which was 13.96 and 34.89% more than 70 and 100% water requirement, respectively. A strong and significant negative correlation was observed between the traits of fruit length, fruit volume, vitamin C, and antioxidant capacity and the set of traits of fruit weight, water use efficiency, relative water content, leaf chlorophyll, and fresh plant weight. Based on the results of this research, changing irrigation from 100 to 85% water requirement not only saves water but also improves the plant's resistance to common problems such as blossom-end rot and increases the shelf life of the fruits. So, an 85% level of irrigation is recommended for this variety of pepper under controlled conditions.

Physalis peruviana L. is a short perennial shrub that is a member of the Solanaceae family. These fruits have many benefits for human health because of their nutritional and bioactive compounds (vitamins (A, B, C and K), essential fats and etc.) and reduced the risk of diseases such as cancer, malaria, asthma, hepatitis, dermatitis and rheumatism. Therefore, it has received special attention for cultivation all over the world. Increasing crop production and mitigating abiotic stresses are major challenges under extreme climatic environments and intense farming activities. Crop management strategies such as deficit irrigation can decrease soil evaporation, runoff, and plant transpiration, and increase water use efficiency (WUE) and water conservation. In addition to these practices, organic input, which includes the application of organic materials such as compost and humic substances, is an additional strategy that increases soil water retention and can potentially improve plant WUE. Water is crucial for agriculture and needs to be used effectively due to climate change and drought in Iran. For this reason, to adapt to water deficit scenarios, deficit irrigation applications are increasing in importance. Water availability is expected to be a growth limiting factor that would affect fruit yield in Physalis peruviana due to reduced flower set and elevated floral abscission rate.

In order to investigate the effect of humic acid on physiological characteristics, yield and fruit quality of Physalis peruviana under deficit irrigation conditions, a split plot experiment based on randomized complete block design with three replications was conducted during 2021. Treatments consisted arrangement of three levels of irrigation (starting irrigation at 100, 80 and 60% ETc (crop evapotranspiration)) and three levels of humic acid (0, 1.5 and 3 kg ha-1). The seeds of Physalis peruviana were sown in seedling trays contain peat moss. The seedlings were grown under normal conditions (25±2 °C/day and 20±2 °C at night with 60-65% RH). Plant height, total chlorophyll, fruit yield per plant, total soluble solid content, titratable acidity, vitamin C content and water use efficiency were measured. Statistical analyses were performed with SAS V9.3, and means comparison were separated by Duncan’s multiple range tests at p < 0.05.

Results and Discussion :

The results showed that deficit irrigation significantly reduced growth, fruit yield, vitamin C and increased water use efficiency (WUE) and Total soluble solid content of Physalis peruviana. The soil application of humic acid significantly increased total chlorophyll, fruit quality and yield, and decreased leaf electrolyte leakage under normal and deficit irrigation, thus, the deficit irrigation 60 ETc% decreased the plant height by 18.6% and the fruit yield by 22.2% compared to irrigation 100 ETc%. The maximum plant length (200.3 cm), total chlorophyll content (2.42 mg g-1FW) and fruit yield (4793.3 kg ha-1) were observed in plants treated with 3 kg ha-1 humic acid under 100% ETc irrigation. The highest value of total soluble solid (12.6 B°), antioxidant activity (90.06 %) and WUE (1.23 kg m-3) were obtained with 3 kg ha-1 soil application of humic acid under deficit irrigation 60% ETc. The application of 3 kg ha-1 humic acid under 100 and 80 %ETc irrigation increased the fruit yield by 25% and 4%, respectively, compared to the control plants (non treated with humic acid) under irrigation100 ETc% and under deficit irrigation  60 ETc%, with decreasing 11% fruit yield, water consumption was saved by 40%. Soil and crop management practices that alter plant water and nutrient availability could affect the processes of crop evapotranspiration and WUE, which can influence the yield and fruit quality by changing the internal nutrient and water balance. Incorporating organic matter within a crop growth system either as leaf spray or soil mix is a complementary strategy to improve crop growth and WUE. By inducing antioxidant enzyme activities, HS could assist plants in stomata functioning, thereby closing stomata more efficiently under drought stress, which results in plant water conservation. The reason of the difference between WUE values probably appeared due to the differences on Physalis peruviana yield. WUE showed an upward trend with an increasing in irrigation.

Study results suggest that soil application of humic acid with increasing vitamin C, TSS and TA, improved fruit quality. According to the results, application of 3 kg ha-1 humic acid is suggested to improve fruit yield and quality of Physalis peruviana under normal and deficit irrigation conditions.

Considering the abundant use of chemical fertilizers in agriculture and their detriments to the environment, it is necessary to consider alternatives to prevent possible damage.

A completely randomized factorial experiment with four replications was conducted in the Nur country to investigate the imapct of nitroxin and vermicompost on the qualitative and functional characteristics of Blackberry. The first factor was the percentage of vermicompost at five levels (0, 10, 20, 30 and 40% by volume) and the second factor consisted of inoculation and lack of inoculation with nitroxin (Ni).

The results demonstrated that the highest fruit weight, number of fruits, and yield were observed at 20% vermicompost. Maximum fruit length (1.62 cm) was obtained with 10% vermicompost and nitroxin inoculation. In analyzing the biochemical traits, the highest soluble solids and taste index were observed in the 10% vermicompost treatment. The largest amount of anthocyanin was obtained in the 20 and 30% vermicompost treatments at 551 and 563 (mg/L fruit juice), respectively. The application of nitroxin along with 30% vermicompost yielded  the highest amount of vitamin C among all treatments.

The application of vermicompost at 20 to 30% levels had the best impact on the quantitative and qualitative traits of Blackberry, and in cases where high amounts of vermicompost exerted a negative effect on some traits, nitroxin was able to reduce this effect and enhance certain traits. In this assay, the application of vermicompost at 20-30% along with nitroxin demonstrated the best impacts on blackberry traits.

Peppers are a popular fresh product in the market, but they have a limited shelf life. This study aimed to assess the influence of different types of packaging on weight loss, amount of ascorbic acid, total phenols, flavonoids, and antioxidant capacity in sweet peppers during storage. The study compared five types of packaging: nylon freezer wrap, zip-kip bags, cellophane, plastic boxes, and paper cartons. Overall, peppers stored in plastic containers exhibited lower weight loss compared to those stored in cartons (the control group). The most significant decreases in total phenols, flavonoids, and vitamin C content were observed in peppers stored in cartons. Conversely, bell peppers stored in freezer bags, zip-kip bags, and cellophane maintained higher levels of ascorbic acid, phenolic compounds, and flavonoids than the control group. In general, the control group showed the highest losses in phenolic and flavonoid content, while the lowest losses were observed in peppers stored in freezer bags and zip-kip bags. Peppers stored in zip-kip bags and freezer nylon demonstrated higher antioxidant capacity compared to those stored in other types of packaging and the control group. Overall, the use of polyethylene bags, such as freezer bags and zip-kip bags, proved to be more effective in preserving the bioactive compounds of sweet peppers during storage.

In order to investigate the effect of mixing sea and underground water on the morphological and biochemical properties of the purslane medicinal plant, an experiment was conducted in the form of a completely randomized design with three replications in the research greenhouse of Gorgan University of Agricultural Sciences and Natural Resources. The water source treatments included full groundwater (GW100-SW0) as a control, mixing 50% seawater and groundwater (GW50-SW50), half between seawater and groundwater (0.5-GW-SW), and one-half between seawater and Groundwater was (1-GW-SW). The results showed that the use of these water resources at the level of 1% was significant on the fresh and dry weight of root and shoot, height, total chlorophyll, vitamin C and total soluble sugar. Also, these treatments were significant on the amount of chlorophyll a and b, carotenoid and proline at the probability level of 5%. The highest amount of shoot fresh weight, root fresh weight, height and vitamin C were respectively in the control treatment with 61.5 grams, 47.5 grams, 33.2 cm and 74.6 mg per 100 grams of sample fresh weight. The findings show that in most traits, the treatment (0.5-GW-SW) has no significant difference with the control. Therefore, considering the limitation of fresh water sources, the latter treatment is suggested as a suitable source for watering purslane.

Various methods of stress directly affected the growth and production yield of numerous plants. For example, environmental stress reduces the tomato manufacturing by the disrupting its natural metabolism, or, salinity stresses affect the it is growth and development from the germination stage to the fruit ripening stage. Salinity in tomatoes by stimulating the biosynthesis of growth regulators such as ethylene and abscisic acid leads to the acceleration of the aging of the leaves. Therefore, development of different methods to induce salinity stress tolerance in plants is necessary. Some approaches were studied to develop the salinity tolerant plants such as genetic breeding, environmental improvements and usage of phytohormones and signal molecules. Salicylic acid or orthohydroxybenzoic acid plays an important role in regulating the physiological and biochemical responses of plants to stress conditions, which improves the plant's resistance to adverse environmental conditions. For instance, salicylic acid is a facile and effective way to increase plant productivity under salt stress conditions. Considering the positive effects of salicylic acid in modulating the effects of salinity, this study was conducted with the aim of investigating the effects of salicylic acid’s usage in modulating the harmful effects of salinity on some vegetative, physiological, quantitative and qualitative characteristics of two tomato cultivars of Baneh local mass and Semi Dwarf line.

To investigate the effect of salicylic acid in modulating the effects of salinity stress in tomato, a factorial experiment was conducted in the form of a randomized complete block design, with 12 treatments, in 3 replications and with a total of 36 experimental units in the hydroponic greenhouse of the Department of Horticulture, Faculty of Agriculture, and university of Tabriz. The treatments included two levels of salicylic acid (0 and 1 mM) and salinity levels (0, 35 and 70 mM NaCl) on two tomato cultivars of Baneh and Semi Dwarf.

The results showed that in Baneh and Semi Dwarf cultivars, the increase in salinity levels caused a decrease in vegetative indices, meanwhile the treatment of salicylic acid along with salt stress increased same indices. Also, salt stress caused yield reduction in both Baneh and Semi Dwarf cultivars. By examining the qualitative indicators, it was observed that titratable acidity and vitamin C increased with salt stress and salicylic acid treatment in both cultivars. In terms of physiological indicators, the amount of proline increased at different salinity levels with salicylic acid treatment, but the amount of leaf chlorophyll index decreased with the increase of same condition.

The results of testing the effect of salicylic acid and the effects of salinity stress on vegetative, quantitative, qualitative and physiological indicators in Baneh and Semi Dwarf tomatoes showed a remarkable difference in terms of significance. In terms of vegetative traits; Plant height, leaf area index, shoot wet in Baneh and Semi Dwarf cultivars decreased with increasing salinity levels of vegetative indices, but salicylic acid treatment along with salinity stress increased same indices. Indicators such as yield, fresh weight of fruit, and percentage of dry matter of fruit showed different responses to different levels of salinity and salicylic acid treatment. The fresh weight of fruit increased with the application of salicylic acid. Also, salt stress caused an increase in the percentage of dry matter of the fruit. But salt stress caused yield reduction in both Baneh and Semi Dwarf cultivars. In terms of quality indicators; the amount of titratable acidity and vitamin C increased with salt stress and salicylic acid treatment in both cultivars. In terms of physiological indicators, the level of proline increased across various salinity levels with salicylic acid treatment. However, the leaf chlorophyll index decreased with rising salinity levels, even in the presence of salicylic acid treatment. Overall, salinity stress caused a decrease in most analyzed traits in the Baneh and Semi Dwarf cultivars. Nevertheless, it led to improvements in certain quality traits. Additionally, salicylic acid treatment enhanced the mentioned indices in most of the examined traits in both cultivars. Therefore, considering the positive effects of salicylic acid treatment on Baneh and Semi Dwarf cultivars under salinity stress conditions, its use is recommended.

Long-term use of chemical fertilizers can cause many adverse effects. In addition, excessive consumption of chemical fertilizers can lead to decreased food safety and low quality of vegetables, such as the accumulation of nitrates in plants. Today, using organic fertilizers is an efficient way to achieve sustainable agricultural development. The release rate of nutrients from organic fertilizers is slow and hardly exceeds the absorption capacity of plants compared to chemical fertilizers.

To compare the effect of chemical and organic fertilizers on the quantitative and qualitative traits of tomatoes in field conditions, an experiment was conducted in the cropping year of 2020-2021 in a randomized complete blocks design with three replications in the research farm of the Faculty of Agriculture, Ferdowsi University of Mashhad, Iran. Experimental treatments included: 1- biochar (8 t.ha-1), 2- animal manure (30 t.ha-1), 3- vermicompost (25 t.ha-1), 4- NPK chemical fertilizer (225 kg.ha-1 urea, 150 kg.ha-1 phosphorus fertilizer and 150 kg.ha-1 potassium sulfate), 5- 50% biochar + 50% animal manure, 6- 50% biochar + vermicompost, 7-50% animal manure + 50% vermicompost, 8- 50% biochar + 50% NPK, 9- 50% animal manure + 50% NPK, 10- 50% animal manure + 50% NPK, 11- 25% biochar + 25% animal manure + 25% vermicompost + 25% NPK and 12- control. The harvesting operation was carried out in two cutting. Five plants were randomly selected in each plot, and traits such as fruit size, length, and diameter were measured. Also, total yield, Brix index, vitamin C, and lycopene were measured in both cuttings.

In the first and second cutting, the highest fruit volume was obtained in the treatment of NPK chemical fertilizer (80.5 cm-3) and the combined use of NPK chemical + animal manure (131 cm-3), respectively. In the first cutting, the maximum fruit length was reported in the treatment of NPK chemical fertilizer (5.61 cm), and the second cutting, in the combined application of NPK chemical fertilizer + animal manure (7.16 cm) that compared to the control (4.73 cm) had a longer fruit length of 51%. The largest fruit diameter was observed in the NPK chemical fertilizer treatment (5.01 cm), which was 16% more than the control (4.31 cm). On the other hand, in the second cutting, the largest fruit diameter was shown in the combined application of chemical NPK + manure (5.54 cm). In the first cutting and the total of both cuttings, the highest yield was observed in the treatment of NPK chemical fertilizer (39.6 and 70.5 t.ha-1, respectively), while in the second cutting, the highest yield was obtained in the combined treatment of NPK chemical fertilizer + animal manure. (32.8 ton.ha-1). The results showed that using organic fertilizers individually and combinatorial compared to NPK chemical fertilizers had more Brix index, vitamin C, and lycopene. The highest amount of Brix index in first and second cutting (6.55 and 7.13, respectively), vitamin C (12.9 and 11.4 mg.100 g sample-1, respectively), and lycopene (2.48 and 2.25 mg.100 g sample-1, respectively) in the combined treatment of animal manure + vermicompost. Since the elements in the chemical fertilizer are released faster than the elements of other fertilizers and are available to the plant, therefore, by increasing the initial growth of the plant and as a result of improving its flowering potential, the total yield increased, in particular in the first cutting, where the superior treatment was the NPK chemical fertilizer. Further, due to the gradual release of organic fertilizer elements, the combined treatment of chemical and organic fertilizers increased the yield. On the other hand, organic matter plays an important role in soil fertility and performance. The rare elements in organic matter can meet the needs of soil microorganisms, enhance microbial activities, affect soil-microorganism interactions, and indirectly affect crop quality.

The use of organic fertilizer, when combined with chemical fertilizer, can enhance both the qualitative and quantitative characteristics of tomatoes. By substituting a portion of chemical fertilizer with organic fertilizer, not only can yield be improved, but it's also possible to reduce the consumption of costly chemical fertilizers. This approach aligns with sustainable agricultural goals by optimizing the use of organic fertilizers.

The increase in people's awareness of the negative effects of chemical preservatives has led to more research on the antimicrobial effect of plant essential oils and their potential to be used as preservative compounds. Strawberry (Fragaria   ananassa cv. qingxiang) is one of the most popular and widely consumed berries due to its taste, sweetness and healthy function. The taste of strawberry is related to its hardness, viscosity, sugars, protein, total soluble solid, titratable acidity content and minerals like P, K, Ca and Fe. It is a good source of polyphenolic compounds such as flavanols and has antioxidant activity. This, together with higher vitamin C content in strawberries, contributes beneficial effects on the maintenance of consumer health. Strawberry has higher antioxidant activities than orange, grape, banana, apple, etc. Strawberries are among the fruits sensitive to mechanical and physiological damage and have a fast metabolism and deterioration during the storage period. For this reason, it is necessary to use safe methods to control spoilage and maintain the quality of strawberry fruit during storage.

 The experiment was conducted in a completely randomized design, in a 5 x 4 factorial scheme (5 treatments x 4 periods evaluated), with four replications The first variable was the type of material with different concentrations in five levels including 0, 0.3%, 0.6% carvacrol, the combination of chitosan with 0.3% and 0.6% carvacrol, and the second variable was storage time in four periods including 0, 10, 20, 30 days of storage. The harvested fruits were kept at  4°C and with a relative humidity of 90±5% and parameters such as weight loss, pH, firmness of the fruit tissue, acidity (TA), soluble solids (TSS) and taste index, vitamin C, phenol and flavonoid, fruit shelf life (number of days) during the storage period were investigated and studied.

 The ANOVA results showed that the effect of the type of treatment and storage time on all investigated traits except for the firmness of the fruit texture was significant at the probability level of 1%. The fruits treated with the combination of chitosan and carvacrol 0.6% had more texture firmness, vitamin C, total phenol content and the amount of soluble solids and better shelf life than the control. In all four storage times, the highest content of total phenol (2.49 mg of gallic acid per 100 gr FW), total flavonoid (0.435 mg of Quercetin per 100 gr FW) and firmness (3.80 N) was related to the combined treatment of chitosan with carvacrol 0.6% and the lowest amount was related to the control. The firmness of the fruit tissue gradually decreased during storage, but this process was observed at a significantly slower rate in the treated fruits.

Considering the increase of 10 and 12 days of shelf life post- harvest of the combined treatment of chitosan + 0.6% carvacrol compared to other treatments and the control, hence the application of chitosan pre harvest and the use of 0.6% carvacrol edible coatings can be recommended as a safe and low-cost strategy to increase the shelf life post harvesting of 'Parus ' strawberry cultivar.

Sweet pepper is a rich source of essential vitamins and minerals. On the other hand, pepper fruit contains high levels of antioxidants and beneficial substances such as vitamin C, carotenoids and phenolic compounds. It also contains high concentrations of potassium. These compounds has nutritional and antioxidant capacity. Sweet pepper originated from the tropical region, which is sensitive to cold. Therefore, it is necessary to know the defense mechanism of the pepper plant against low temperatures. In this study, the effect of foliar application of salicylic acid and vermicompost on different cultivars of sweet pepper under cold stress has been studied.

The experimental design was a factorial split-plot experiment in a randomized complete block design with three replications in a greenhouse located in Mashhad in the crop year 1396 and 1397. Cultivation was performed hydroponically. The main factor of temperature treatment had two levels [9 ± 2°C (cold stress) and 23 ± 2°C (optimum)] and the sub factor consisting of two sweet pepper cultivars (green, yellow) and Different amounts of Salicylic acid (The dose of 0 μmol salicylic acid was used as control group, 200, 300 μmol) and vermicompost). Sampling of the plants at the end of the growing season, to measure the physiological characteristics and quality were randomly.

The results showed that there was no significant difference between different cultivars in most traits except vitamin C, beta-carotenoids and lycopene. Maximum dry matter (17.2g), TA (13.6 g l-1) in non-stress cold treatment, and soluble solids (5.03 brix),, carbohydrates(174.5 mg g-1), and anti-activity Oxidation (90.3%)  were obtained in cold stress treatment. Damage due to cold stress destroyed the structure of many membrane lipids and resulted in an increase in the amount of antioxidant compounds. Soluble solids are known to be key components in increasing cold resistance. An increase in the amount of soluble solids in winter is part of the plant's adaptation mechanism to cold. The highest yield of fruit per plant(740 g) was obtained in non-cold stress treatment plus salicylic acid 300 μmol. Because salicylic acid in plants improves yield and yield components. Maximum of flavonoids (159.4 mg g-1) was obtained in salicylic acid 200 μmol. Flavonoids are a large group of phenolic compounds in plants that increase their production in environmental stresses by increasing the activity of PAL enzyme. On the other hand, the use of salicylic acid as a stressor causes the production of a wide range of flavonoids. The highest amount of beta-carotene and lycopene were obtained in cold stress treatment, yellow cultivar, and salicylic 300 μmol. Decreased content of carotenoids under stress can be due to oxidation by active oxygen and damage to their structure. Increased photosynthetic pigments under SA treatment indicate the protective effect of this growth regulator on photosynthesis and photosynthetic pigments of stressed plants. Maximum vitamin C was obtained in cold stress treatment (140.7 mg 100 g-1, yellow cultivar (134.7 mg.100g-1), and salicylic 300 μmol (142.52 mg.100 g-1).

According to the results, the of the present study show that use of salicylic acid foliar application modulates the effect of cold stress on the physiological and functional parameters of sweet pepper so that SA can improve cold tolerance by regulating the activities of apoplastic antioxidative enzymes. Therefore, it is suggested that due to sudden changes in temperature due to climate change and the destructive effects of temperature stress, especially cold, on plants, more and more complete research should be done to identify the effects of these stresses and ways to deal with them.

Due to the limitations in the use of chemical compounds, one of the alternative methods is to use natural compounds in the storage of products. Therefore, the present study was performed to investigate the effect of Aloe vera gel (at a concentration of 100%) and different levels of lemon peel essential oil (0, 100, and 150 μl/l) on some physicochemical and qualitative characteristics of apricot fruit (Nouri cultivar) during three storage period (1, 10 and 20 days) was conducted as a factorial experiment in a randomized complete base design with 3 replications. In each storage period, weight loss percentage, total soluble solids (TSS), titratable acidity (TA), flavour index, vitamin C, pH, fruit shelf life and total count of mold and yeast were examined. The results showed, the highest weight loss was related to the control (without aloe vera gel and essential oil) treatment on the twentieth day after fruit storing. The highest flavor index was related to the treatment composition of Aloe vera gel coating on the tenth day. The highest amount of vitamin C was related to the treatment composition of Aloe vera gel coating and 100 µl / l of essential oil of lemon peel on the tenth day after storing. The number of molds and yeast colonies was observed in the control treatment and the lowest growth rate of molds was observed in the Aloe vera gel treatment with 100 μl / l of lemon peel essential oil .In general, the use of aloe vera gel with 100 μl / l of essential oil of lemon peel as a natural combination improved the quality characteristics of the apricot fruit (Nouri cultivar) in tenth days after fruit storing by an increase to the TSS, and vitamin C, and reduced to weight loss and growth of microorganisms. Therefore, these compounds can be introduced as a suitable method in the post-harvest technology of this fruit.

Drought is one of the most important environmental stresses in the ecosystem of crops. In order to select potato tolerant genotypes to drought stress.

This experiment was conducted in the form of a randomized complete block design with the method of strip chopped blocks in three replications during the two cropping years was performed in Ardabil region. Two levels of non-stress and stress irrigation were compared as vertical factor and 20 potato genotypes were compared as horizontal factor.

The results showed that all measured traits were affected by stress treatments. Under stress treatment, genotype 905675 had the highest tuber yield and tuber weight per plant. The lowest tuber yield and tuber weight per plant were obtained from Marfona cultivar. In addition, with the application of stress, the activity of enzymatic and non-enzymatic antioxidants increased. The highest amount of reducing sugar with 122%, vitamin C with 63%, proline with 106% The percentage of catalase enzyme with 249% increase compared to non-stress conditions was observed in genotype 905675. The highest activity of superoxide dismutase and polyphenol oxidase with 214 and 42% increase belonged to genotype 901375, respectively.

In general, considering the amount of changes in tuber yield, tuber weight per plant, increasing the activity of enzymatic and non-enzymatic antioxidants, genotypes 905675, 901575 and 901375 were selected as tolerant and high yield potential genotypes in both stress and non-stress conditions, respectively, and Milva, Jelly and Marfona cultivars can be introduced as susceptible cultivars.

The objective of this study is to evaluate the effect of different methods of complementary pollination on the qualitative characteristics of kiwifruit cv. Hayward in order to introduce the most effective and practical complementary pollination method.

The present study evaluated the effect of different methods of complementary pollination [open pollination, hand pollination from male flowers of the tumor cultivar, spray pollination with pure pollen and spray pollination with impure pollen (collected from the entrance of bees' nests at the time of opening kiwifruit male flowers) on the qualitative characteristics of kiwifruit cv. Hayward in the Citrus and Subtropical Fruits Research Institute (Ramsar city) in 2021 based on the randomized complete block design in three replications.

The results showed that the amount of titratable acids, maturity index, chlorophyll b, carotenoid, total flavonoid and antioxidant activity were not affected by different methods of complementary pollination. Fruits obtained from spray pollination with impure pollen had the highest single tree yield (98.32 kg per tree), hectare yield (40.39 tons per hectare), number of seeds (1038), amount of soluble solids (7.07 °Brix), chlorophyll a (1.71 mg100 g-1 FW), total chlorophyll (3.11 mg100 g-1 FW), vitamin C (60.27 mg100 g-1 FW), and total fruit phenol (79.62 mg100 g-1 FW). Moreover, these fruits were in more favorable conditions regarding sensory and taste evaluations.

Overall, it is possible to recommend complementary pollination according to spray pollination with impure pollen as the most effective and practical method to increase fruit quality for kiwifruit growers.

Quality indices are important goals of the tomato breeding program. This study was conducted with the aim of investigating the genetic structure of different tomato lines and hybrids obtained from complete di-allele crosses. In this research, genetic analysis of important traits related to tomato fruit weight and quality such as antioxidant capacity, total flavonoid, total phenol and vitamin C was investigated. Variance analysis of data was done in the form of randomized complete block design and di-allele analysis by Griffingʼs Method I. The variance analysis of the data showed a high significant difference between the genotypes for all the studied traits. The variance significance of GCA: SCA ratio for the traits of average fruit weight, total phenol and total flavonoids showed that the contribution of additive effects in controlling these traits is greater than the non-additive effect of genes and the selection method can improve these traits and reach cultivars with more weight Fruit, total phenol and flavonoids, is beneficial. While the traits of vitamin C and antioxidant capacity were controlled by the non-additive effects of genes. Therefore, considering that the selection potential for these traits is not high, hybridization-based methods can be used to improve these traits.

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.

Identifying and evaluating the variations in growth, performance and composition of crops is important for breeding and improving the quality of products. In this study, in addition to evaluating the qualitative and quantitative characteristics of five radishes (Raphanus sativus) cultivars, their compatibility with saline soil under the arid climate of Isfahan was investigated. The seeds of Isfahan local, Cherry Bell, Champion, Breakfast and Sparkler cultivars were planted in the fall based on a randomized complete block design and their characteristics were measured at the commercial maturity stage. Sparkler, Breakfast and Isfahan local cultivars had the highest growth and yield. The tubers of the cultivars were almost spherical in shape, and elongated tubers were observed only in Breakfast. Radish tubers showed considerable differences in terms of dry matter percentage (5.9-9.2%). The acidity of the tuber extract was not significantly different among the cultivars (pH 6.5±0.1), but the electrical conductivity of the tuber extract was significantly different (1.2-2.2 dS/m) and had a direct relationship with potassium content. The cultivars were significantly different in terms of the content of soluble solids (1.7-6.3 ˚Brix), titratable acid (6.2-9.1 g/100g) and their ratio (1.4-2-7). The content of vitamin C was 9.3-1.16 mg/100g; therefore, radish cannot be considered as a rich source of vitamin C in the diet. Radish had a significant amount of potassium (130-220 mg/100g) which is equivalent to about 10% of the consumer's daily requirement. Phosphorus concentration in tubers of radish cultivars (200-398 mg/kg) was lower than potassium. The differences in radish cultivars were related to genetic differences in vigor and differences in high soil electrical conductivity tolerance. For saline soils and arid climates, Sparkler, Breakfast and Isfahan local cultivars were suggested for autumn radish cultivation.

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.