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 ...
Read More
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.
Pomology
A. Mslahate fard; H. Hassanpour
Abstract
Introduction: The pistachio genus (Pistacia) belongs to Anacardiaceae family. Three species of common pistachio (P. vera, P. khinjuk and P. atlantica) was found in Iran. Bene )P. atlantica (is a dicotyledonous tree with a height of more than 17 meters, is the most important species of Zagros region with ...
Read More
Introduction: The pistachio genus (Pistacia) belongs to Anacardiaceae family. Three species of common pistachio (P. vera, P. khinjuk and P. atlantica) was found in Iran. Bene )P. atlantica (is a dicotyledonous tree with a height of more than 17 meters, is the most important species of Zagros region with valuable main and secondary products. This tree was also used as a rootstocks for edible pistachios and resistant to adverse environmental conditions, so that it grows in different climates in terms of land slope, soil type, different soil fertility levels, altitude (600 to 3000 meters) and temperature range of -25 to 40 °C. Fruit and gum have different uses in food, industry and medicine. Medicinal and oral uses of Bene fruit and gum have long been reported not only in Iran, but also among the natives of all coriander-rich regions, including parts of Algeria, Turkey and Iraq. Bene fruit can be harvested at three stages; First, the unripe stage (in the form of small hollow spheres without a kernel), its skin is brittle and its color is pale green. The second stage, the kernel is completely hardened, but the shell has an ocher red color that tastes sour. The last, the ripe stage, the kernel is completely hardened and the color of the skin is blue-green.
Materials and Methods: This study was conducted to evaluate the diversity and determine some quantitative and qualitative characteristics of different Bene) P. atlantica (genotypes at the green fruit stage. For this purpose, 11 genotypes were randomly selected in an area near the city of Mirabad, West Azerbaijan Province, Iran. The fruits were harvested from each genotype and transferred to the laboratory. In this study, some quantitative traits of fruit and cluster as well as total phenol, total flavonoids and total antioxidant capacity were analyzed. Digital calipers were used to measure the length and width of fruit and clusters (mm). Also, a digital scale with an accuracy of 0.001 g was used to measure the weight of fruit and cluster. Fruit size index was calculated by multiplying the measured width by the measured length and expressed as mm2. Total antioxidant capacity was assessed using the DPPH (1, 1-diphenyl-2-picrylhydrazyl) method. Folin–Ciocalteu method was used to measure the total phenol content.
Results and Discussion: The results showed that cluster weight had the highest diversity and fruit width had the least diversity among the studied traits. Traits such as cluster width, cluster length, total phenol and flavonoid content were also highly varied among genotypes. In this study, the maximum weight, length and width of fruit were 1.28 g, 8.32 and 8.62 mm, respectively. Also, the results of this study showed that there is a significant difference between genotypes in terms of all parameters measured except cluster length at the 1% and 5% of probability level. Overall, the results of this study showed high variability in the majority of traits. The highest length, width and weight of the cluster as well as the width and weight of the fruit were seen in P10 genotype and the lowest was observed in P5 and P6 genotypes. In terms of biochemical characteristics, P3 genotype had the highest total phenol (1034.5 mg gallic acid per gram of FW), total flavonoid (143.82 mg quercetin per gram FW) and antioxidant capacity (93%) and also, the lowest total phenol (370.08 mg gallic acid per gram of FW), total flavonoids (62.25 mg catechin per gram FW) was observed in P7 genotype. According to results of this study, P3 and P10 genotypes can be used for medicinal, food, industrial purposes as well as breeding purposes compared to the other genotypes.
Conclusion: In this study, it was shown that there is a high diversity in the majority of measured traits among different genotypes. The highest morphological traits were observed in P10 genotype. Also, in terms of biochemical characteristics, genotype P3 had the highest total phenol, total flavonoid content and total antioxidant capacity. According to the results, it can be concluded that the morphological characteristics as well as phenolic, flavonoid compounds and antioxidant capacity depend on various factors, including genetic factors and environmental and ecological conditions. Therefore, the observed diversity can be related to genetic structure of genotypes, which can also be considered as a kind of adaptation and physiological response of trees to environmental conditions.
M. Fateh; T. Barzegar; F. Razavi
Abstract
Introduction: Sweet pepper (Capsicum annuum L.) is a worldwide used vegetable, 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 ...
Read More
Introduction: Sweet pepper (Capsicum annuum L.) is a worldwide used vegetable, 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. In recent years, the application of exogenous AsA has received much attention for use as a biologically safe compound for postharvest quality maintenance of many horticulture crops. Calcium is an essential micronutrient that 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 effect of ascorbic acid and calcium lactate on pepper fruits. Thus, the aim of this study was to investigate the foliar application of ascorbic acid and calcium lactate on growth, yield and fruit quality of sweet peppers.
Materials and Methods: To study the effect of foliar application of calcium lactate (Ca) and Ascorbic acid (AsA) on growth, yield and fruit quality of sweet pepper, the field experiment was carried out from June to September 2016 at Research farm of faculty of Agriculture, at the University of Zanjan, Iran. Pepper plants (cv. California Wonder) were cultivated by applying conventional farming practice for growing in open air conditions. 210 plants (30 plants for each treatment) were selected for uniform size and fruit load, and were sprayed three times (0, 15, 30 days after full bloom) with an aqueous solution containing different concentrations of Ca (0, 0.5, 1 and 1.5 g L-1) and AsA (100, 200 and 300 mg L-1). Each treatment was carried out with three replicates. Pepper fruit were harvested at commercial maturity stage, and transferred to the laboratory on the same day. Leaf area was recorded whit measurement leaf area (DELTA-T DEVICEC LTD, ENGLAND). After fruit harvested, plant length was measured. Fruit was weighted after harvest to determine mean fruit weight. The fruit number per plant and fruit yield per plant was measured to determine of total yield. The total yield expressed in kg ha–1. 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 foliar application of AsA had significant effects on growth and fruit yield. The highest fruit yield (897.1 g plant-1) was achieved at 300 mg L-1 AsA that had no significant difference with 200 mg L-1 AsA. Foliar application of AsA markedly increased vitamin C content, and also the highest value of total soluble solid (5.7 °B) was recorded from 300 mg L-1 AsA. Ca had no significant effects on growth and fruit yield but significantly improved fruit firmness. The highest fruit firmness (2.13 and 2.16 kg cm-1) was obtained from 1 and 1.5 g L-1 Ca. The maximum antioxidant activity was achieved with application of 300 mg L-1 AsA and 1.5 g L-1 Ca. The fresh sweet peppers were an important source of ascorbic acid for human consumption. AsA significantly increased the amount of vitamin C in the plum and sweet pepper fruits. Foliar treatment of Ca increased vitamin C content. 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 exogenous application of AsA and Ca in sweet pepper plants indicated that treatments had significant effects on ascorbic acid content of sweet peppers. 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 increased plant growth, fruit number and weight. Also, AsA and Ca treatments 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 1.5 g L-1, may be proposed to improve fruit quality.
karim arabsalmani; Amirhooshang Jalali; Peyman Jafari
Abstract
Introduction: Cucumis melo L. is one of the most important horticultural products in Iran. According to some reports from the third millennium BC, it has been under cultivation in. High nutritional value and high vitamin A, vitamin C, calcium, potassium, magnesium and iron have made it to be a valuable ...
Read More
Introduction: Cucumis melo L. is one of the most important horticultural products in Iran. According to some reports from the third millennium BC, it has been under cultivation in. High nutritional value and high vitamin A, vitamin C, calcium, potassium, magnesium and iron have made it to be a valuable fruit. According to the environmental conditions and cultivar, melon flowering began 30-60 days after planting and 30-70 days after pollination, the product can be harvested. Immature melon is tasteless and towards maturity, its sweetness increases. From the economic point of view, the minimum acceptable sweetness of melon's cultivars is 9% in terms of the total amount of fruit-soluble solids, but according to the vendors, this number should be 11% or more. The arid and semi-arid regions of the world are the main habitat for such products as melon and salinity stress as an integral part of these areas is an important factor for decreasing yield. The effect of salinity stress in melon's reproductive stage is somewhat more complex than other products, because some reports indicated a significant decrease in yield, number of fruit and weight of melon fruits in salinities greater than 2 dS m-1 and even some researchers determine the threshold of tolerance of 1 dS m-1. The present study was conducted to investigate the effect of two salinity treatments on yield and yield components of three melon cultivars in Varamin province.
Materials and Methods: This research was carried out in 2013 using split plot design in a randomized complete block design with three replications in Varamin Agricultural Center located in 45 km Southeast East of Tehran (35 ° 35 ', 19', 51 ', 39') 1000 meters above sea level. Prior to the experiment, the first step was to prepare the soil including deep plowing and disc. The main plots consisted of irrigation water salinity treatments at 8 dS m-1 (prepared from the Ishraq area) and 2 dS m-1 (prepared from the Khaveh station). The subplots consisted of 3 Cantaloupe masses, including Semsoori Varamin, Green Tile of Mashhad and Magasie Neishabur. The soil of the place-tested sandy loam and the amounts of organic matter (in percent), acidity and salinity (in dS m-1) were 0.95, 7.5 and 2.1 respectively. Based on the soil test, 100 kg ha-1 phosphorus (triple superphosphate) and 150 kg ha-1 potassium (as potassium sulfate) and 150 kg ha-1 nitrogen fertilizer (urea before and after flowering) were added to the ground the experiment. The cultivation date was selected May 5th. The length and diameter of the flesh with the ruler and the percentage of fruit-soluble solids were measured using a refractometer based on 10 fruits, and then the mean of the obtained numbers was taken as the final value. Before harvest, the average number of fruits per plant and average fruit weight were measured and recorded based on the performance of sub plots and the middle lines of each plot. All soil and vegetation tests were carried out in the laboratory of the Soil and Water Research Department of Varamin Agricultural Research Center. Statistical analysis was performed using SAS software and the meanings were compared with Duncan's method (5%).
Results and Discussion: The effect of interaction of salinity and genotype on the length of the fruit (at 1% level) and on the traits of seed cavity thickness, percentage of soluble solids, fruit meal diameter, fruit weight and fresh yield (at 5% level) were statistically significant. In salinity 8 dS m-1 compared to 2 dS m-1, the fresh yield of Semsuri Varamin, Green Tile of Mashhad and Magase Neishabur decreased by 32.7, 45.6 and 80%, respectively. Salinity stress can increase the percentage of non-marketable fruits by reducing the weight of fruits, and it is reported in salinity of 8 dS m-1, which is a 56% decrease in marketable yield. The highest reduction in fruit weight and number of fruits per plant were related to the two mass of Magase Neishabur (average weight 540 g) and Green Tile of Mashhad (average number of 1.23 fruit per plant), respectively. Similarly, in a research with a salinity increase of 2.41 dS m-1 to 12.6 dS m-1, yields dropped from 37 t ha-1 to 28 t ha-1, mainly due to the reduction in the number of fruits. The length of fruits in three populations of Semsuri Varamin, Green Tile of Mashhad and Magase Neishabur in the salinity of 8 dS m-1 compared to 2 dS m-1 decreased by 25, 30 and 45%, respectively. Increasing salinity from 3 to 5 dS m-1 caused a significant decrease in fruit length in products such as cucumber (equivalent to 25%). Increasing the percentage of fruit solids in salinity of 8 dS m-1compared to 2 dS m-1 treatment, was 5.8, 1.75 and 1.5 times, respectively, in the Magase Neishabur, Green Tile of Mashhad and Semsuri masses. In a study in which the effect of different treatments on salinity was investigated on the percentage of soluble fruit solids, increasing salinity from 2 to 8 dS m-1 increased the percentage of soluble solids from 7.6 to 10.5 percent.
Seied Mehdi Miri; Meysam Salari; Ahmad Ahmadpour
Abstract
Introduction. Citrus is one of the most commercially important horticultural crops grown in tropical and sub-tropical regions of the world. They are classified as non-climacteric fruits. Harvesting date and storage can influence citrus fruit quality and shelf life. In Iran, some members of citrus family ...
Read More
Introduction. Citrus is one of the most commercially important horticultural crops grown in tropical and sub-tropical regions of the world. They are classified as non-climacteric fruits. Harvesting date and storage can influence citrus fruit quality and shelf life. In Iran, some members of citrus family including sweet orange and mandarin are produced as an export crop, so research on fruit quality and storage life is needed. There is no available scientific literature regarding the effect of harvesting date and storage duration on retaining the postharvest physicochemical properties of Kinnow mandarin under cold storage. The main objective of the present study was to evaluate the effect of harvesting date and storing time on shelf life and quality of Kinnow mandarin fruits under Jiroft weather conditions.
Materials and Methods. Investigations were carried out on mandarin (Citrus reticulata) cv. Kinnow grafted on sour orange rootstock in an orchard located in Jiroft and Kahnooj Agricultural Research Center, Jiroft, Iran. Fruits were harvested on 6th December, 21th December, 5th January, 20th January and 4th February. After cold storage for 30-90 days at 4-6 °C, the fruit was analyzed for quantitative and qualitative characteristics including weight of fruit, peel, meat, pulp and juice, fruit weight loss, pH, total soluble solids (TSS), titratable acidity (TA) and TSS/TA. Experiment was arranged in a split plot based on randomized complete block design (RCBD). Data analysis and similarity coefficient (Pearson's method) were performed using SPSS.16 software, and means comparison was performed by using Duncan's multiple range test at 1 and 5% probability levels.
Results and Discussion. The results showed that the interaction effect of harvesting date and storage period on the weight of the fruit, meat, pulp and juice and TSS, TA and TSS/TA was significant at 1% probability level. Weight of harvested fruits from 6th December to 5th January was constant, but fruits harvested on 20th January and 4th February were heavier as much as 12.5 and 14.3 percent, respectively, compared to 6th December. Fruit weight loss increased along with the increase in storage time duration, so that mean fruits weight loss percentages were 3.5 and 16.5 at 30 and 90 days of storage, respectively, due to continued transpiration of the fruits after harvesting. As a result of transpiration, water enters into the atmosphere through the pores existing on fruit surface. The greatest fruit weight (121.8 g) was recorded for combination of harvesting on 20th January and 30-day storage. Fruits harvested on 20th January and 30-day storage had higher meat and pulp weight (89.6 and 52.3 g, respectively) and a significant correlation coefficient was detected between them. Changes of fruit juice pH at different stages of fruit ripening and storage times did not follow a fixed pattern, though pH slightly increased in some cases during storage, which can be due to oxidation of citric acid during storage. The maximum TSS was recorded for harvesting on 5th January and 90-day storage (11.7 °Brix) as well as 4th February and 60- and 90-day storages (11.8 °Brix), while the minimum TSS was observed on 6th December and 30-day storage (8.7 °Brix). The results exhibited that TSS content of fruit juice increased when storage period increased, which was possibly attributed to the hydrolysis of starch and increase in sucrose content. However, increase in TSS during storage is not always directly related to changes in the simple sugar content of fruit. During storage and maturation of the fruits on the tree, TA reduced due to the use of citric acid in respiration. Taste index (TSS/TA) in fruits harvested at full maturity was greater than that in fruits harvested in the fall. Besides, TSS/TA increased during storage, so that the highest and lowest average TSS/TA ratios were related to harvesting on 4th February and 30-day storage as well as 6th December and 30-day storage, respectively. According to the results, fruits did not reach full maturity until 5th January under Jiroft weather conditions.
Conclusion. Postharvest quality and shelf life of Kinnow mandarin fruits were affected by harvesting date and storage duration. Delay in harvest resulted in an increase in fruit weight, TSS and TSS/TA. TSS and TSS/TA were higher when fruits harvested on 4th February. Fruit weight loss increased when the storage period increased.. Overall, 4th February is the best date to harvest Kinnow mandarin fruit in Jiroft.
R. Barzegar; Sadollah. Hooshmand; Gh. Peyvast
Abstract
In order to evaluation of squash (Cucurbita pepo) seed yield per fruit and its relations with other characteristics of fruit include: length, diameter, length: diameter ratio (fruit shape), flesh thickness, thousand seed weight and fruit weight, an experiment was conducted using 24 accessions of squash ...
Read More
In order to evaluation of squash (Cucurbita pepo) seed yield per fruit and its relations with other characteristics of fruit include: length, diameter, length: diameter ratio (fruit shape), flesh thickness, thousand seed weight and fruit weight, an experiment was conducted using 24 accessions of squash as a randomized complete-block design with three replications. Morphological traits were evaluated according to UPOV descriptor and UPGMA clustering algorithm clustered the accessions in 4 groups (predominantly on the basis of fruit shape). Correlation, regression and path analysis were done for mentioned characteristics in 4 type-fruit groups. There was negative correlation between seed yield of individual fruit and its length and fruit length: diameter ratio. But fruit weight, fruit diameter, and thousand seeds weight had positive correlation with seed yield. Seed weight: fruit weight ratio had negative relationship with fruit weight. Therefore small size fruit is more suitable for seed yield per area. Path analysis was showed fruit weight had the most positive direct effect on seed yield per fruit in all groups.
