Growing vegetables
Zahra Khalili; Fatemeh Nekounam; Taher Barzegar; Zahra Ghahremani; Maliheh Farhangpour
Abstract
Introduction: Tomato (Solanum lycopersicum L.) belongs to the Solanaceae family, which is one of the most widely cultivated and economically important vegetables in the world, which is an excellent source of ascorbic acid and has high antioxidant capacity against oxidative damage caused by free radicals. ...
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Introduction: Tomato (Solanum lycopersicum L.) belongs to the Solanaceae family, which is one of the most widely cultivated and economically important vegetables in the world, which is an excellent source of ascorbic acid and has high antioxidant capacity against oxidative damage caused by free radicals. Ascorbic acid (AsA) is a water-soluble vitamin that plays a key physiological role in scavenging reactive oxygen species (ROS), and enzyme cofactor. Ascorbic acid is antioxidant and antistress agent, and also acts as a signaling molecule in some plant physiological processes and defense mechanisms. Positive roles of such antioxidants in scavenging or chelating the free radicals and activating the natural resistance against different biotic and abiotic stresses have been reported in several fruit trees. Calcium has a vital role for normal growth and development of plants due to an important role in balancing membrane structures, increasing nutrient uptakes and activates of metabolic processes. Calcium plays a vital role in maintains cell wall stability, integrity and determining the fruit quality. To our knowledge, however, little information is available regarding the interaction effect of ascorbic acid and calcium chloride on tomato. Thus, the aim of this study was to investigate the foliar application of ascorbic acid and calcium chloride on quality and antioxidant capacity of tomato fruit.Materials and Methods: To study the effect of foliar application of calcium chloride (Ca) and Ascorbic acid (AsA) on growth, yield and fruit quality of tomato, the field experiment was carried out from June to September 2021 at Research farm of faculty of Agriculture, at the University of Zanjan, Iran. Each treatment was carried out with three replicates. Different concentrations of Ca (0, 0.3, 0.6 and 0.9 %) and AsA (0, 100, 200 and 300 mg L-1) were sprayed three times (0, 15, 30 days after full bloom). Fruits were harvested at two harvests stage (orange and red color) and transferred to the laboratory on the same day. Flesh firmness was determined with penetrometer (model Mc Cormic FT 32), using an 8 mm penetrating tip. Results were expressed in kg cm-2. The pH values of solutions were monitored with pH meter. TSS was measured in the extract obtained from three fruit of each replicate with a digital refractometer Atago PR-101 (Atago Co., Ltd., Tokyo, Japan) at 20◦C. Total ascorbic acid content was expressed as mg per 100 g of juice. Antioxidant activity was measured using the free radical scavenging activity (DPPH) and calculated according to the following formula: RSA%= 100(Ac-As)/Ac. Statistical analyses were performed with SPSS software package v. 20.0 for Windows, and means comparison were separated by Duncan’s multiple range tests at p <0.05.Results and Discussion: The results showed that fruit harvested at red color stage had the higher vitamin C, total soluble solid (TSS), total phenol, flavonoids contents and antioxidant capacity compared to fruit harvested at orange color stage. Foliar application of AsA and Ca had significantly improved tomat fruit quality. The highest value of TSS (4.9 °B), vitamin C (46.1 mg 100ml-1), total phenol and flavonoids contents and antioxidant capacity (36%) was achieved with application of 300 mg L-1 AsA and 0.9% Ca in fruit harvested at red color harvest time. The lowest value of pH and highest TA was observed in red color fruit treated with 300 mg L-1 AsA and all Ca levels. Ca had significant effect on fruit firmness, which the highest fruit firmness was obtained from 0.9% Ca. The fresh tomato is an important source of ascorbic acid for human consumption. AsA significantly increased the amount of vitamin C in the plum and sweet pepper fruits. Increasing vitamin C content in fruits after treatment with Ca could be related to inhibiting action of calcium on the activities of ascorbic acid oxidase that use ascorbate as a substrate. The results indicated that treatment of Ca produced fruits with higher firmness compared to control and other treatments. Firmness and resistance to softening can be increased by the addition of Ca, due to interaction of calcium with pectate acid in the cell wall to form calcium pectate and retarding polygalacturonase activity. Differences in the percentage of TSS content at the time of harvest indicated the AsA and Ca effects on carbohydrate accumulation in fruits, which had different potential on respiration rates and consequently storability of plants. The antioxidant activity has positive correlation with total phenolic content, flavonoids and content of ascorbic acid. Conclusion: The results of our research indicated that per-harvest foliar application of AsA and Ca improved fruit quality attributes including vitamin C, fruit firmness, TSS and antioxidant activity. These results suggest that AsA and Ca treatments, especially AsA 300 mg L-1 and Ca 0.9%, may be proposed to improve fruit quality.
Breeding and Biotechnology of Plant and Flower
leila baghazadeh; Davood Samsampoor; Abdoolnabi Bagheri; Jelveh Sohrabipour
Abstract
Introduction: Endophytes have symbiosis life within the plant tissues without causing any obvious negative effects. Seaweeds are one of the large and diverse groups of marine plants that play an essential role in marine and oceans ecosystems. Seaweeds show rich diversity of associated microorganisms ...
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Introduction: Endophytes have symbiosis life within the plant tissues without causing any obvious negative effects. Seaweeds are one of the large and diverse groups of marine plants that play an essential role in marine and oceans ecosystems. Seaweeds show rich diversity of associated microorganisms in compare with the other multicellular organisms. Citrus species, are amongst the most important evergreen fruit trees, cultivated in many countries worldwide. There are several obstacles for citrus production in southern of Iran, limiting continuity of citrus production. Lack of suitable soil, salinity and drought stresses are the main challenges threatening citrus industry in southern of Iran. Similar to other citrus species, the production of Mexican lime is threatened by certain biological stresses (such as pests, plant diseases and weeds) and non-biological stresses (such as salinity, drought, floods, cold and heat stress). Endophytes are advantageous group of microorganisms that protect plants from biotic and abiotic stresses. One of the alternative ways to restore normal plant growth may be to use plant growth to stimulate endophytes. Endophytes can play an important role in plant growth. Endophytes from marine environment are gaining special interest because of their existence in the harsh conditions of marines and ocean ecosystem such as temperature, light availability, high salinity and osmotic stress. Endophytes have already been isolated from various marine habitat, including marine plants, marine invertebrates and vertebrates. Among these organisms, seaweeds are one of the most prevalent sources of marine-derived fungi and bacteria for chemical studies. The purpose of this study was the isolation of associated fungi and bacteria endophytes with seaweed species in Persian Gulf to investigate morphological and molecular characterization by using PCR amplifications ITS1-5.8S-ITS4 regions and 16s rRNA gene respectively. Here, we have evaluated the potential of inoculating Mexican lime seedlings with seaweeds fungi and bacteria endophyte combination, (Aspergillus niger+ Bacillus aquimaris OD14), to improve morphological, biochemical, antioxidant and photosynthesis pigments characterizes of Mexican lime in salinity condition.Materials and Methods: The main aim of this study was to investigate the role of endophytic fungi (Aspergillus niger) and bacteria (Bacillus aquimaris OD14) in improving the growth of Mexican lime seedlings. The seaweed samples were collected from coastal regions of Bushehr province and Qeshm Island. Fungi and bacteria endophytes were isolated and identified base on morphological and molecular methods. Molecular characterization was investigated using PCR amplification of ITS1-5.8S-ITS4 regions and 16s rRNA gene respectively. Mexican lime seeds were sterilized with 0.5% sodium hypochlorite for 20 minutes and then completely distilled three times with distilled water. Seedlings pots containing autoclaved soil were placed in the greenhouse of the Faculty of Agriculture, Hormozgan University. The experiment was arranged in a factorial experiment based on randomized complete randomize design with three replications. Isolated fungi and bacteria by MT420720 and MT278260 accession numbers were used in eight months old Mexican lime seedlings. The suspension was adjusted to a concentration of 1×106 cell per ml for fungi and 1×108 cell per ml for bacteria inoculums. For better contact of seedlings with endophytes, inoculation was performed three times. After three months, salinity stress was applied. morphological (Leave, Stem and Root dry and fresh weight), biochemical (Protein, MDA and soluble sugars), antioxidant capacity (CAT, POD, SOD, APX and Gr activity) and photosynthesis pigments (Chlorophyll a, Chlorophyll b, Total Chlorophyll and Carotenoids) characteristics in treated Mexican lime seedlings and control were analyzed. Analysis of variance of traits was performed using SAS software version 9.4 and the means were compared using LSD method with a probability level of P≤0.05.Results and Discussion: The results show that most characterizes were significant compare with control. For example, in 6000 µs/cm water salinity, leave fresh weight (203.49%), root fresh weight (347.41%), stem fresh weight (206.81%) and root dry weight (421.95%) were significantly higher compared with control (P>0.001). Endophytes inoculation can significantly improve photosynthesis pigments such as chlorophyll a (65.21%), chlorophyll b (11.9%), total chlorophyll (28.39%) and carotenoids (59.09%) (P>0.001) compare with control. In antioxidant capacity of seedling, CAT, POD, SOD, Gr and APX were analyzed, Endophytes can increase enzymes activity. For biochemical characterizes, in 6000 µs/cm water salinity, endophytes can significantly increase soluble sugars (17.85%) and decrease MDA (35.18%) in inoculated seedlings compare with control (P>0.001). Conclusion: The results showed that the use of endophytic fungi and bacteria can increase the growth of Mexican lime seedlings under salinity stress. Thereby it can be used as an effective tool for growing salinity-sensitive plants in saline conditions.
Pomology
Zohre Rohi Vishekaii; Ali Soleimani; Mahmmod Ghasemnezhad; Akbar Hasani
Abstract
Introduction Olive tree, with a thousand years of cultivation history, is one of the most important horticultural crops in Iran and has always played an important economical role for orchardists. In olive orchards traits such as an increased formation of incomplete flowers, low yield of fruits and ...
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Introduction Olive tree, with a thousand years of cultivation history, is one of the most important horticultural crops in Iran and has always played an important economical role for orchardists. In olive orchards traits such as an increased formation of incomplete flowers, low yield of fruits and oil are often found as major problems. It should be noted that these traits are affected by numerous environmental and management factors from which the nutrition status is one of the most important ones. Proper nutrition plays an important role in both olive fruit and oil yield. There is a wide range of fertilizer compounds with different formulas and efficiencies available in the world market, among which nano-products are becoming increasingly popular. However, there is limited information on their efficacy in different plant species. Materials and MethodsIn order to evaluate the impact of fertilizers on olive cultivation, a research was conducted during two successive years from 2019 to 2020 in a commercial orchard on 15 year old olive tree cv. ‘Zard’, in Manjil city of Guilan province. Foliar application included five treatments using two types of fertilizers; nano (nano-chelated nitrogen and potassium: nano-NK) and chemical fertilizers (urea and potassium nitrate; NK). Treatments involved application of two concentrations from each fertilizers sources; 1.02g and 0.81g (nano-N1K1 and N1K1), 1.36 g and 1.08 g (nano-N2K2 and N2K2) of pure nitrogen and potassium, respectively. Foliar application was conducted in four stages bud-swelling, before blooming, pit hardening and shortly after harvest of table olive. Spraying with water was considered as the control. The nano-chelated fertilizers were obtained from Khazra Company, Teheran, Iran (http://en.khazra.ir). Spraying with water was considered as control. The experiment was performed in a randomized block design with three replications. The measurement of leaf nutrient status and its chlorophyll and carbohydrate contents were carried out at two times each growing season; in August (during pit hardening stage) and October (shortly after the harvest of table olive). At the green ripening stage, fruits were collected and weighted to determine fruit yield. At the end of the experiment quantity and quality traits of oil were measured. Results and Discussion The results showed that the trees under N2K2 treatment had the highest yield. In terms of mineral content, both forms of fertilizers increased the concentration of nitrogen and potassium leaf elements compared to the control trees. Chlorophyll content was affected by nano-N1K1 foliar application and carbohydrate content was affected by nano-N1K1 in the pit hardening stage and nano-N2K2 in shortly after the harvest of table olive. Nano-N1K1 treatment with the lower crop load not only increased oil content but also improved quality characteristics of olive oil (free fatty acids, peroxide value, specific ultraviolet absorbance K232, K270 and contents of pigments), total phenol content, antioxidant capacity and fatty acid composition. Generally, the results showed that olive trees responded well to fertilizer feeding. These trees produced better crop and higher quality oil in comparison with control trees. According to the results, fruit yield is better under urea and potassium nitrate treatment, and the quality of olive oil is more stable after nano-chelated nitrogen and potassium foliar application. It seems that the reason for the high amount of fruit yield with N2K2 in comparison to the slow-release property of nano-fertilizers is that using nitrogen and potassium in the form of ordinary chemical fertilizer regulates the biosynthesis, conversion and rapid translocation of assimilates and mineral elements into reproductive structures, which resulted in soaring yield. We assumed that nano-N1K1 foliar spray in the pit hardening stage and shortly after the fruit harvest for table olive might export the assimilation into the fruit to fulfill cell metabolism requirements for oil synthesis. Conclusion The current findings indicated that two of four treatments, i.e. nano-N1K1 and N2K2, could be more effective on olive trees in terms of general fruit and oil attributes. It was remarkable that nano treatment with a lower concentration could provide adequate beneficial effects on quality characteristics of olive oil and is in line with good management strategies regarding the preservation of the environment. To the best of our knowledge, the current work is the first report considering the application of nano-chelated nitrogen and potassium and their is use as a foliar application on olive trees. Additional studies would be necessary to further optimize the concentration and timing of the applications with these new formulations.
Growing vegetables
M. Ghoreyshi; F. Nekounam; T. Barzegar; J. Nikbakht
Abstract
Introduction
Water stress is the most prominent abiotic stress limiting agricultural crop growth and productivity. Deficit irrigation stress as a consequence of the progressive decrease in water availability has been a hot topic regarding food security during the last two decades. Growth and development ...
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Introduction
Water stress is the most prominent abiotic stress limiting agricultural crop growth and productivity. Deficit irrigation stress as a consequence of the progressive decrease in water availability has been a hot topic regarding food security during the last two decades. Growth and development of plants is influenced by reduction in turgor that results in decreased nutrient acquisition from dry soil. When water supply is limited, plant growth and yield is reduced and plant structure is modified by decreasing in leaf size. The effect of deficit irrigation on fruit yield and quality has been reported by numerous researchers with different results. In melon, deficit irrigation reduced marketable fruit number and yield, average fruit weight, fruit diameter and did not affect rind thickness and seed cavity, but increased total soluble solids content. Although the effects of water stress have been studied on growth and yield of different crops during the last years, recent information on the response of African horned cucumber yield and quality to deficit irrigation remains limited, particularly about the results of restricted water distributions in arid and sub-arid environments. The main goal of this study was to evaluate the effect of controlled deficit irrigation on growth, physiological parameters and yield and fruit quality of African horned cucumber.
Material and Methods
Field experiment was performed based on a completely randomized block design with three irrigation regimes (60, 80 and 100 %ETc), whit three replications at Research Farm of University of Zanjan during the 2019. The African horned cucumber seeds were sown on 1th July 2020 at recommended spacing of 50 cm in row with 120 cm between rows. The irrigation system consisted of one drip line every crop row. The three irrigation levels were calculated based on actual evapotranspiration (ETc): (1) control, irrigated 100% crop water requirement, (2) deficit irrigation 80% ETc and (3) deficit irrigation 60% ETc. The Water requirement of the plant for control treatment was estimated using long-term average daily data of meteorological parameters recorded at Zanjan Meteorological Station and following relation. Before starting the differential irrigation at five-leaf stage, all treatments were supplied with similar amount of water to maximize stands and uniform crop establishment. During plant growth, the relative water content, proline content, electrolyte leakage, chlorophyll and carotenoids, P and K contents were measured. After fruit harvest, vine length of each plant, leaf dry weight and stem diameter were measured. The fruits were harvested when color changed from green to yellow. Fruit weight, fruit number per plant and fruit yield per plant was measured. Immediately after harvest, fruit firmness, total soluble solid, total phenols content, antioxidant capacity and vitamin C were determined.
Results and Discussion
As the results showed water deficit stress significantly reduced plant length, chlorophyll content, and increased carotenoids content. Based on the findings, deficit irrigation caused a significant reduction in leaf relative water content. According to the results, phosphorus and potassium contents in African horned cucumber leaves decreased with deficit irrigation treatments. The highest P and K contents were found under irrigation 100 %ETc treatment. Drought stress and associated reduction in soil moisture can decrease plant nutrient uptake by reducing nutrient supply through mineralization. The proline content increased with the deficit irrigation treatments; in particular with sever deficit irrigation (60 %ETc). Mean comparisons of data showed that deficit irrigation led to a significant increase in electrolyte leakage compared to control.
Water deficit stress caused significant reductions in yield. The highest fruit number per plant and yield were obtained under irrigation 100% ETc. The average fruit weigh significantly increased in response to increase water deficit stress. Deficit irrigation treatments significantly decreased vitamin C and fruit firmness. Significant differences among irrigation treatments were observed for total phenols and total soluble solid contents. The phenols and total soluble solid contents increased with the decrease of irrigation water applied. Antioxidant capacity was affected significantly by the irrigation treatments, and water deficit stress increased antioxidant capacity, which no significant difference was observed between irrigation 100 and 80 %ETc.
Conclusion
Water deficit has been shown to adversely affect plant growth, fruit yield, and leaf water status of African horned cucumber, but led to increase the TSS and antioxidant capacity. According to the results, fruit yield reduced 13.9 % under irrigation 80% ETc compared to irrigation 100% ETc, However, water consumption was saved by 20% and improved fruit weight and fruit quality with increasing soluble solids and antioxidant capacity.
Postharvest physiology
M. Ghafouri; F. Razavi; M. Arghavani; E. Abedi Gheslaghi
Abstract
Introduction Nowadays, the application of chemical compounds is limited due to their harmful effects on human and the environment health. The benefits of seaweeds as sources of organic matter and fertilizer nutrients have been known to agriculture for centuries, especially in coastal areas extracts ...
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Introduction Nowadays, the application of chemical compounds is limited due to their harmful effects on human and the environment health. The benefits of seaweeds as sources of organic matter and fertilizer nutrients have been known to agriculture for centuries, especially in coastal areas extracts of these seaweeds have been used for decades as foliar- and soil-applied treatments in crop production systems due to the presence of a number of plant growth-stimulating compounds. Unlike chemical fertilizers, extracts derived from seaweeds are biodegradable, non-toxic and non-hazardous to humans, animals and birds. Therefore, it is required to find a safe compound that is utilized in the postharvest technology of fruit and vegetables. Pre-harvest application of nutrient solutions such as seaweed increases the quality and quantity of crop and also enhance their storage life and marketability. Various researchers reported that aqueous extracts of seaweed increased the yield and quality of tangerine and orange, strawberry, grape, apple, and watermelon fruit. Thus, the aim of the current study was to investigate the effect of pre-harvest foliar application of Seaweed extract on quality and quantity values, antioxidant properties, and storage life of kiwifruits.Material and Methods This experiment was carried out on 10-year-old kiwifruit vines, in a commercial orchard located in Gilan Province. Vines were selected with uniform size in terms of growth, yield and fruit load, then sprayed with seaweed extract at four levels of 0, 1, 2 and 3 g.l-1 as a foliar spray and control vines only received water. Foliar spraying was performed in three stages, (110, 125 and 140 days after full bloom stage) and Tween 20 was used as a surfactant. This experiment was designed as factorial based on randomized complete block design with three replications. The fruits were harvested in November with soluble solids content (TSS) of 6.5-6.2% and then transferred to the post-harvest physiology laboratory of the University of Zanjan. The treated fruits were stored for 90 days at 1 ° C with 90% RH. Sampling was done at harvest time and after 30, 60 and 90 days of storage and some quantity and quality traits such as weight loss, tissue firmness, TSS, ascorbic acid, total phenol and flavonoids, antioxidant capacity and the activity of superoxide dismutase (SOD) and phenylalanine ammonia-lyase (PAL) enzymes were evaluated.Results and Discussion The ANOVA results showed that seaweed extract, storage time, and interaction of seaweed extract × storage time had a significant effect (p≤0.01) on evaluated traits. All treatments maintained the antioxidant capacity, total phenol and flavonoids content and PAL activity at a higher level compared with control. The amount of fruit tissue firmness, TA and ascorbic acid decreased by increasing the storage time, and at the third month of storage, the lowest amount was observed in the control fruit. Also, comparing the interaction of the mean of treatments and storage time showed that pH, weight loss, TA, TSS, antioxidant capacity, total phenol, flavonoids and PAL enzyme activity increased by increasing the storage time. At the end of the storage time, the highest level of TSS, weight loss and pH were observed in the control fruit. The lowest antioxidant capacity (48.14 %) was observed in the control treatment at harvest time and the highest antioxidant capacity was observed in 3 levels of brown algae extract treatment at the end of storage period. Comparison of means showed that at the first 30 days of storage, the highest PAL enzyme activity was observed in the treatment of 3 g / l of brown algae. PAL enzyme activity significantly increased after the experiment. At the end of storage period, the lowest PAL enzyme activity was observed in control fruit. Treatment of 3 g / l brown algae had higher PAL activity. PAL, as a key enzyme in phenylpropanoid metabolism, catalyzes the conversion of phenylalanine to trans-cinnamic acid, which is the first step in the biosynthesis of phenylpropanoids and leads to the production of secondary metabolites such as lignin, phytolaxoids, and flavonoids. The direct and positive relationship of this enzyme with the synthesis of phenols and flavonoids has been discovered in the fruits of blood orange, strawberry and blueberry. The results of the comparison of the mean showed that the total phenol and flavonoids increased by increasing the storage time. The lowest phenol (23 mg GAE.100 g-1 FW) was observed in control fruit at harvest and the highest (8.88 mg GAE.100 g-1 FW) content of total phenol was observed in 3 levels of brown algae extract at the third month of storage. Plants release phenolic compounds in response to some messenger compounds that play an important defense role. Studies show that there is a positive relationship between total phenol content and their antioxidant activity. Flavonoids are also polyphenolic compounds and are the most important secondary compounds of plants. Under oxidative stress, in plants, the activity of propanoid pathway increases, especially the pathway of flavonoids biosynthesis. Flavonoid compounds are abundant in plants and show antioxidant activity. Seaweed extract enhances the antioxidant capacity of the fruit and thereby inhibits oxygen-free radicals Treatment of 3 g/l seaweed extract had the best effect among the treatments applied in maintaining firmness, fruit weight loss, TA, antioxidant capacity, total phenol and flavonoids and PAL enzyme activity. All three levels of seaweed extract increased the amount of total phenol, flavonoids and antioxidant capacity all over the storage time, but no significant difference was observed among the treatments levels. Based on the results, the application of 3 g/l seaweed extract effectively increased the antioxidant capacity and PAL enzyme activity during 90 days of storage time. As a result, seaweed extract treatment had positive effects on maintaining the quality and increasing the shelf life of kiwifruit during 90 days of storage.ConclusionSeaweed extract is one of the natural compounds and compatible with human health and nature has medicinal and nutritional value that can increase the shelf life and maintain fruit quality in the postharvest period. In summary, foliar application of seaweed extract has a significant effect on fruit firmness, total soluble solids, total acid, vitamin C, phenol and total flavonoids, total antioxidant activity and the enzyme phenylalanine ammonialyase. The appropriate treatment for kiwifruit cultivar ‘Hayward’ is introduced. Among the applied treatments, 3 g/l of seaweed extract had the best effect on firmness (40.40%), fruit weight loss percentage (41.87%), titratable acid (25.37%), vitamin C (33.26%), antioxidant capacity (26.70%), total phenol (81.17%), total flavonoids (103.67%) and PAL enzyme activity (153.75%) compared to the control in 90 days of storage.
.M Mozaffari; .F Razavi; .V Rabiei; .A Kheiry; A. Hassani
Abstract
Introduction: Demand for healthy and high-quality fruits has increased in the markets, and compositions such as vitamins, sugars, and anti-oxidant properties of fruits have attracted many consumers. Grapes contain phenols, flavonoids, anthocyanins, tannins and vitamins with high antioxidant properties. ...
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Introduction: Demand for healthy and high-quality fruits has increased in the markets, and compositions such as vitamins, sugars, and anti-oxidant properties of fruits have attracted many consumers. Grapes contain phenols, flavonoids, anthocyanins, tannins and vitamins with high antioxidant properties. Antioxidants support biological systems such as proteins, amino acids, lipids, and DNA against oxidative damage produced by active oxygen species of ROS, resulting in reduction of cell damage and death, cardiovascular disease and cancers in the human body. Selenium is essential for humans and animals and should be fed through a diet, for this reason, FAO recommends entering selenium to agricultural products (especially fruits and vegetables). In recent years, selenium has been recognized as a useful element for plants that have been toxic at high concentrations but at desirable concentrations, it has positive antioxidant effects, increases growth and significantly affects seed germination. Selenium protects plants from several abiotic stresses such as heavy metal and arsenic, ultraviolet radiation, and biotic stress such as pathogens and pests. Selenium neutralizes oxidative stress interfering with lipid peroxidation, and accelerates gluthatione peroxidase (GSH-Px) activity, this phenomenon delay plant senescence and diminish postharvest losses. This element increases the yield and improves the quality of the fruits and vegetables. When Camelia oleifera plants were treated with selenium, cellular content of linoleic acid and sterol were elevated but oleic acid content diminished. Selenium treatment had a significant effect on preserving the sensory and the postharvest quality by decreasing respiration rate and ethylene biosynthesis in broccoli by diminishing phenylalanine ammonia-lyase (PAL) activity and ethylene production in lettuce and chicory. Foliar application of peach and pear trees with selenium, decelerated fruit softening rate and elongated shelf-life. Therefore, treatment of agricultural products with the appropriate amount of selenium can have a positive effect on the increase of the quality and enrichment of selenium in fruits and also play an important role in human health.
Materials and Methods: In order to investigate the effect of selenium as foliar application (0, 1, 2 and 3 mg L-1) on quality traits, antioxidant compounds and enrichment of grape cv. Fakhri, an experiment based on randomized complete block design with three replications in a vineyard (Kurdistan Povince, Ghorveh town) was performed. The 15-year-old vines were sprayed with selenium solution plus 0.1% of Twin 20 as surfactant until the leaves were completely wet (for each vine about 0.5 liter) at three stages of berry growth and development: Berry formation, Lag phase and veraison. A 1000 mg L -1 stock solutions (Made by the Belgian company CHEM-Lab, containing selenium ion Se+6) was used to prepare the desired solutions. At commercial fruit maturity stage (20° Brix), samples of fruits and leaves randomly were collected from treated and control vines and were immediately transferred to the postharvest physiology laboratory. Traits such as total chlorophyll, carotenoid, nitrogen, potassium, selenium content of leaves and fruits, and also, total soluble solids, soluble sugars, titrable acidity, acidity (pH), vitamin C, phenol and flavonoids, antioxidant capacity in fruits and the berry weight were evaluated. Data were analyzed using SAS statistical software (SAS V.9.4), and means were compared by Duncan’s multiple range tests at the 5% of probability level.
Results and Discussion: Results showed positive effects of selenium treatment on evaluated traits. As a result, 2 mg L-1 of selenium increased photosynthetic pigments, nitrogen and leaf potassium, soluble solids, soluble sugars, vitamin C, total phenol, antioxidant capacity of fruits in comparison with untreated vines. The highest amount of titrable acidity, total fruit flavonoid and leaf selenium was recorded in vines treated with 3 mg L-1 selenium, whereas, this treatment had less effect on other traits. The highest amount of berry weight was obtained in 1 mg L-1 of selenium. However, none of the selenium treatments had significant effect on the juice acidity (pH). In general, the results showed a positive effect of selenium on improvement of antioxidant properties, quality and enrichment of grape, and 2 mg L-1 selenium with the highest effect on traits was identified as the best treatment. According to other researchers, foliar application of selenium in "Starking Delicious" apple cultivar was effective in enhancement of fruit selenium content and nutritional properties, postponing the flesh firmness decrease, and delaying fruit ripening resulting from less ethylene production, therefore significantly affecting apple fruit quality and storage life.
farzaneh badakhshan; farideh sedighi dehkordi; mohammad hassan mortazavi
Abstract
Introduction: Basil (Ocimum basilicum L.), is considered as one of the main edible crops of Lamiaceae family. In addition of consuming as a leafy vegetable, basil is known as a medicinal plant due to its aromatic and phytochemical compositions. The common edible basil has two main varieties i.e. Green ...
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Introduction: Basil (Ocimum basilicum L.), is considered as one of the main edible crops of Lamiaceae family. In addition of consuming as a leafy vegetable, basil is known as a medicinal plant due to its aromatic and phytochemical compositions. The common edible basil has two main varieties i.e. Green and Opal. Although the production of this plant is highly happened in open farms during hot seasons, recent changes in agricultural policies in terms of year-round production, using less water and increasing the yield and quality, have encouraged the production of basil under controlled environments such as hydroponic systems. The main criteria to proceed a successful hydroponic culture are selecting proper cultivar, planting density and nutrition management. Optimum plant density alleviates the competition between plants and as a consequence, sufficient light and nutrient can lead to higher quantity and quality. This study aimed to discover the impact of plant density on the quality and yield properties of two main varieties of basil under hydroponics system.
Material and Methods: The experiment was done at Shahid Chamran University of Ahvaz during 2015-2016 growing season. A pot experiment was conducted based of Split-plot in time design with three replications. Cultivar (Green and Opal) and planting density (150, 200 and 250 plants per m2) were considered as the main and sub plot respectively. The plants were cut twice and different morphological and biochemical properties including number of leaves, leaf area, leafy parts yield, chlorophyll, carotenoids, soluble solid content, titrable acidity, total phenolic content, antioxidant capacity and essential oil content were analyzed.
Result and Discussion:The results showed that among applied treatments, the highest number of leaves (30.61), leaf area (26140 mm2) and stem fresh weight (3.28 g) were recorded for the var. Green with 150 p/m2 planting density at second cut. In contrast, this treatment had the lowest number of leaves (12.33) and leaf area (10810 mm2) at first cut. While maximum leaf fresh weight (5.84 g) was obtained for second cut of 150 p/m2 planting density, minimum leaf and stem fresh weight (3.09 and 2.01 g respectively) were found for second cut of 200 p/m2 planting density. Total fresh yield as an important criteria for a leafy vegetable was affected by both variety and planting density factors. The highest amount of yield (1427 g/m2) was recorded at second cut when plants were at 250 p/m2. In contrast, the plants of 150 p/m2 had the minimum yield at first cut (1020 g/m2). The chlorophyll content was higher in Opal variety surprisingly and the plants of 250 p/m2 and 150 p/m2 had around 2.09 mg/g chlorophyll at second cut. Similar findings were obtained for total phenolic content of leaves that was around 104.3 mg/Kg fresh weight for these treatments. Lowest levels of chlorophyll (1.29 mg/g FW) and total phenolic content (6.158 mg/kg) were seen in the leaves of var. Green when they were planted at 150 plant/m2 density. The data for total carotenoids content showed that the level of this pigments were affected by both parameters of variety and planting density. The leaves of var. Opal of 250 p/m2 density had the highest (6.252 mg/g fresh weight) carotenoids content. The highest (2.021 mmol Fe II/g FW) and lowest (0.69 mmol Fe II/g) amount of antioxidant capacity was recorded in Opal and Green varieties respectively, when they were at 150 plant/m2 density. The taste related parameters including total soluble solids, titrable acidity and essential oil content were not affected by planting density and variety. However, the level of acidity was increased by increasing plant density. On the other hand, a significant difference was seen in terms of TSS, acidity and essential oil between first and second cuts.
Conclusion: Overall and based on obtained data, it can be said that the var. Opal at 150 and 250 plants/m2 density showed the best results in terms of evaluated morphological and qualitative traits and can be recommended for hydroponics basil cultivation. Basil is harvest in 2-3 cuts and this experiment showed that for almost all vegetative parameters, the second cut had better results. The improved yield and quality at second cut could be attributed to the better establishment of roots and providing higher levels of nutrients.
zahra falati; mohammadreza fattahi; ali ebady
Abstract
Introduction: Plums (Prunus spp.) as one of the most popular stone fruits, have low calories and high nutritional value. Over the past decades global production of European and Japanese plums reached from 6,110,870 tons in 1990 to 11,528,337 tons in 2013. In the same period plum production in Iran reached ...
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Introduction: Plums (Prunus spp.) as one of the most popular stone fruits, have low calories and high nutritional value. Over the past decades global production of European and Japanese plums reached from 6,110,870 tons in 1990 to 11,528,337 tons in 2013. In the same period plum production in Iran reached from 118,936 tons to 305,262 tons. Great variety of plum fruits caused differences in chemical composition as well. Plum fruits are rich in bioactive compounds or biochemicals such as vitamins (A, C and E), anthocyanins and other phenolic compounds which have high antioxidant activity.
Materials and Methods: This research was done in a randomized complete block design with three replications in Horticultural Research Station at College of Agriculture and Natural Resources of Tehran University in 2013-2015. Fruit quality characteristics such as vitamin C content, color traits of the fruit skin and flesh, the content of carotenoids, anthocyanins, total phenolics and antioxidant capacity of 16 plum and prune cultivars and genotypes were evaluated.
Results and Discussion: Analysis of variance showed significant differences in terms of all measured factors. The highest L* index (brightness) of fruit skin was observed in 'Tanasgol" and "Compooti" and then in "Golden Drop" and "Shams" cultivars and the lowest level of that was measured in "Sugar" and "Gogeh Sabz" cultivars. "Black Star" and "Gogeh Germez" Showed the highest brightness of fruit flesh among examined cultivars and the lowest brightness of fruit flesh was investigated in "Sugar". A* color index of skin and flesh of fruit also showed significant differences among investigated cultivars and the highest level of that in "Ozarak" cultivar was observed. "Gogeh Sabz" and "Golden Drop" also had the lowest level of this index. "Gogeh Germez" had the highest of a*color index of fruit flesh and "Japanese" cultivar was in second place. The lowest level of this index was measured in "Ozarak" and "Shams" cultivars. "Tanasgol" and "Compooti" had the highest fruit skin b*color index among cultivars and "Santarsa", "Sugar," "Stanley" and "Bukhara" showed the lowest of that. "Black Star" and after that "Tanasgol" and "Dargazi" had the highest b*color index of fruit flesh. "Japanese" had also the lowest b* color index of fruit flesh. The intensity or color purity varied among cultivars and the highest of that was observed in "Tanasgol" and "Compooti" and then in "Ozarak". "Black Star" had the highest chroma of fruit skin and the highest fruit flesh color intensity. The lowest of this index in the fruit flesh was observed in "Santarosa", "Sugar" and "Japanese" cultivars. Vitamin C (ascorbic acid) content varied in investigate cultivars. "Gogeh Germez" and "Japanese" had the highest vitamin C content and "Stanley" was showed the lowest amount of vitamin C. "Golden Drop ","Santarosa" and "Compooti" showed the highest total carotenoid among examined cultivars and "Gogeh Germez" had the lowest total carotenoid. "Gogeh Germez" and "Compooti" had the highest and lowest amount of anthocyanin index respectively. The highest total phenol and antioxidant activity was measured in "Ozarak". The lowest total antioxidant capacity was in"Gogeh Sabz". The results showed that There was high correlation (r= 0.93) between antioxidant capacity and a* fruit skin color index. High correlation (r= 0.83) between phenol content and antioxidant capacity of fruits was also observed. Between a* color index of fruit skin and phenolic content was observed high correlation (r= 0.89). As well as between anthocyanin and phenolic content and between anthocyanin and a* fruit skin color index, respectively (r= 0.86) and (r= 0.59) high correlation was detected.
Conclusions: "Ozarak" in terms of antioxidant activity and total phenol component was superior. The highest amount of anthocyanin related to the "Gogeh Germez". "Golden Drop"," Santarosa" and "Compooti " had the highest total carotenoid and "Gogeh Germez" and "Japanese" had the highest vitamin C content among investigated cultivars. By identification of superior cultivars In terms of phytochemical compounds, these cultivars can be used in breeding programs to improve these nutritional quality of fruits. The results showed that the major phenolic compounds were gathered on the skin of plum fruits. Hence the "Ozarak" cultivar having the highest a*color index of fruit skin had the highest total phenol and antioxidant capacity among the investigated cultivars but "Gogeh Germez" by having the highest a*color index of fruit flesh and anthocyanins content higher than "Ozarak" cultivar, had low phenolic content and antioxidant capacity compared to the "Ozarak".
sonia jamali; Vali Rabiei; Javad Fattahi Moghadam
Abstract
The effects of coatingtreatments (waxand plasticbags) combined with methylsalicylate on the fruit quality and chilling injury of Moro blood orange were studied during storage. Treated fruits were kept in storage for 80 days at 5 oC and 90-95% relative humidity. Some characteristics such as pulp and skin ...
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The effects of coatingtreatments (waxand plasticbags) combined with methylsalicylate on the fruit quality and chilling injury of Moro blood orange were studied during storage. Treated fruits were kept in storage for 80 days at 5 oC and 90-95% relative humidity. Some characteristics such as pulp and skin total phenolics, antioxidant capacity, total anthocyanin, lipid peroxidation, and the chilling injure index were assessed at 0, 20, 40, 60, 80 days after storage. Total phenolics in the skin and pulp were reduced during storage. Peel Total phenol of wax coating treatment with methyl salicylate (0.26 mg) had the lowest reduction after 80 days storage. Pulp total phenolic of fruits in pair plastic bag fruits (0.25 mg) had minimal changes during storage. Coating combined with methyl salicylate to retain moisture and delay the aging process reduced chilling injury. Generally, the amount of pulp total anthocyanins and antioxidant capacity increased during storage. The antioxidant capacity of the wax coating fruits, pair plastic bag fruits and pair plastic bag fruits combined with methyl salicylate was 42.98, 37.46 and 37.42, respectively. Wax combined with methyl salicylate (0.18 mM) and pair plastic bag fruits (0.17 mM) has the lowest lipid peroxidation during storage. Individual plastic bag with methyl salicylate (44.54%) had the least amount and methyl salicylate (77.41%) had most ion leakage. The best treatments were individual fruit packing combined with methyl salicylate and wax coating combined with methyl salicylate that reduced the incidence of fruit chilling injury to one percent. Ion leakage, lipid peroxidation and chilling injury increased during cold storage. Treated fruit with wax combined with methyl salicylate and individually and pair packed fruit combined with methyl salicylate had the best visual fruit quality. Combined treatments had more effects than individual treatments alone.
M. Hamedani; H. Moradi; A. Ghanbari
Abstract
The different factors such as harvest time, product handling, temperature and storage duration can be influenced on the different properties of citrus fruits and has considerable economic consequences. Therefore a factorial experiment based on completely randomized design with 3 replications was performed ...
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The different factors such as harvest time, product handling, temperature and storage duration can be influenced on the different properties of citrus fruits and has considerable economic consequences. Therefore a factorial experiment based on completely randomized design with 3 replications was performed to evaluate the effects of harvest times (start of color change, 50% of color change and full color change of fruits), storage period (0, 25, 50 and 75 days) at 7ºC on total soluble solids, titrable acidity, ascorbic acid, total phenol content, flavonoid, antioxidant capacity, anthocyanin and activity of L-phenylalanin ammonia-lyase. The results showed that the harvest times and storage period had significant effect on the measured properties. So that the after 75 days of storage, peak phenylalanin ammonia-lyase activity and total flavonoid observed concomitantly with the accumulation of anthocyanin in ripe blood orange fruit but decreased antioxidant capacity and total phenol after 25 days of storage. Also, the highest vitamin C content and total soluble solids were measured in full ripening of fruits before storing and decreased after 75 days storage. So, according to changes in all of measured characteristics, the apropriate time of harvesting of Moro blood orange was the stage of commercial maturity of fruits.
