جستجوی مقالات مرتبط با کلیدواژه « Acidity » در نشریات گروه « باغبانی »

Apple (Malus domestica) is considered as one of the important members of the Rosaceae family and is among the most consumed fruits in the world. One of the biggest challenges for agricultural researchers is to increase the quantity and quality of food to feed the growing population, without negatively affecting the health of the soil and agricultural ecosystems. Due to the adverse effects of chemicals on human health and environmental safety, the production of organic products has been considered as one of the most important issues in food production systems. It is utilized in various forms, including fresh fruit or processed as industrial products. Based on the respiratory and ethylene production pattern, apples are classified as climacteric fruits. Metabolic activities and ripening continue after harvest, so apples have the potential to transform into highly perishable products after harvest. Post-harvest treatments are certainly not the most suitable method for preserving the shelf life and quality of fruits during the post-harvest period. Therefore, employing new and effective methods to enhance quality, control decay, and consequently extend the post-harvest life of apples appears to be essential. Organic farming, as an agricultural system to protect human health and the environment, can improve product quality and shelf life.

This study was conducted on an apple orchard (Malus domestica) in Zarabad area of Khoy city located in the northwest of Iran (with the same management and growth conditions) in 2018-2019. The experiment was conducted as a factorial in the form of a completely randomized block design in 4 replications. The experimental factors included spraying fruit trees with nano-chitosan in 3 concentrations (zero, 5 and 10 ml) and ferulic acid in 3 concentrations (zero, 0.5 and 1 mM). Apple trees in three times, the first stage in the hazelnut time. Fruit drop, the second stage 20 days after the first stage and the third stage 20 days after the second stage spraying, were sprayed in the afternoon using a Cross mark PB20 manual sprayer. The harvested fruits were sprayed according to the treatments were packed and labeled and transferred to the central laboratory of horticultural sciences of Urmia University. After 24 hours of storage at the laboratory temperature, the measurement of the studied traits started on the fruits, the control treatment in this experiment was distilled water with Tween 80 (0.1/v/v).

Compared to the control group, fruits treated with a combination of chitosan and ferulic acid exhibited a significant increase in firmness after harvest. Notably, the most effective treatment involved a combination of 10 milliliters of nano-chitosan and 1 millimolar ferulic acid, resulting in the highest level of firmness among all treatments.As a result, the combined treatment of chitosan and ferulic acid can delay the aging process by reducing the activity of enzymes involved in cell wall degradation and maintain firmness in apples, contributing to a positive effect. According to the obtained results, fruits treated with nano-chitosan and ferulic acid showed a higher soluble solid content compared to the control fruits, and this amount increased with the higher concentrations of nano-chitosan and ferulic acid. The minimum level of TA was observed in the control treatment, and the highest level was observed in the treatment with 10 milliliters of chitosan and 1 millimolar ferulic acid. The treatment with 1 millimolar ferulic acid and 10 milliliters of chitosan showed the highest percentage of TA content compared to the control. The combination of nano-chitosan and ferulic acid treatment led to a reduction in fruit juice pH, with the lowest pH observed in the treatment with 1 millimolar ferulic acid and 10 milliliters of chitosan, and the highest pH observed in the control treatment. Vitamin C is the primary water-soluble antioxidant that directly reduces damage caused by free radicals. According to the obtained results, the maximum content of vitamin C was observed in the treatment with 1 millimolar ferulic acid and 10 milliliters of chitosan. According to the obtained results, the maximum PAL enzyme activity was observed in the treatment with 1 millimolar ferulic acid and 10 milliliters of chitosan.

In general, the findings of the current study showed that pre-harvest treatment with nano-chitosan and ferulic acid had a positive effect on the post-harvest quality of apple fruits. The fruits treated with the highest concentration of nano-chitosan and ferulic acid exhibited the highest fruit firmness, titratable acidity, vitamin C content, PAL enzyme activity, and the lowest pH compared to the control fruits. These results indicate that nano-chitosan and ferulic acid treatment can be proposed as a promising and healthy method for improving the post-harvest quality of apple fruits.

In order to study effect of foliar application of calcium (Ca) and potassium (K) and fruit position in the canopy on physicochemical characteristics of ‘Thomson Navel’ orange trees (Citrus sinensis L. Osbeck, a two-year factorial experiment based on randomized complete blocks design carried out with two factors including the type of foliar spray in four levels (Ca(NO3)2, KNO3, Ca(NO3)2+KNO3, and Control) and fruit position in the tree canopy in two levels (inside or outside) with three replications. The results showed that peel thickness, citrus color index (CCI), and a ratio of total soluble solid to titratable acid (TSS/TA) were higher in the fruits harvested from the outer canopy compared to the canopy inside (P<0.05). Also, the results showed that the peel thickness of the fruit increased with foliar application and the highest increase was found in the foliar spray of K and K+Ca. With Ca foliar application (Ca and K+Ca), TSS and TA significantly decreased compared to the control and potassium foliar application alone, but the ratio between the two indices increased. The results showed that the effect of foliar application on total phenol and antioxidant capacity depends on the position of the fruit on the tree canopy. In conclusion, foliar application of K and Ca cause improve the fruit quality of the ‘Thomson Navel’ sweet orange. Besides, fruit at different canopy positions vary in their physicochemical characteristics and should be harvested separately to have uniform quality and get the maximum economic return.

 Grape (Vitis vinifera L.) is one of the most important economic plants in the world including Iran. One of the most basic effective factors of the growth of fruit trees is knowing their nutrition. Micronutrients are as important as Macronutrients for better growth, yield and quantity in plants. Garden plants suffer from severe zinc deficiency, followed by boron, manganese, iron and molybdenum. Foliar application of fertilizers is a useful tool to increase the nutritional effects of fertilizers or eliminate nutrient deficiencies during the growing season. The aim of this study was to study the nutritional effects of consumption of different compounds of micronutrient fertilizers of zinc chelate, iron and manganese as foliar consumption on the morpho-physiological traits of grape plant.

 Field experiments were carried out to evaluate the effects of micronutrients alone and in combination on growth and fruit yield in grape grown at Iran, Zanjan province during 2016-18.  Physical and chemical properties of the soil were evaluated before the experiment. During the two years of the research, no organic or chemical fertilizers were used except for the combination of fertilizer treatments of the relevant design. Treatments consist of foliar consumption of micronutrients fertilizers included two levels of EDDHA-Zn (0.1 and 0.3 %), EDDHA-Fe (0.1 and 0.2 %), and EDDHA-Mn fertilizers (0.1 and 0.2 %) and control levels (0 %) for them. This experiment was implemented in a factorial format based on a randomized complete block design with three replications and repeated for two consecutive ys.  The measured traits consist of Length of the First inflorescence (X1), Number of Inflorescences per Branch (X2), Number of clusters per branch (X3), Number of Clusters per Plant (X4), Weight of a Cluster (X5), Cluster Size (X6), Berry Size (X7), Number of Berries per Cluster (X8), Weight of single Barry, X10: Leaf Area Surface. Leaf Dry Matter (X11), TSS (X12), Sugar Fruit Juice (X13), Fruit Juice Acidity (X14), Fruit Dry Matter (X15), Fruit Firmness (X16), Yield per Plant (X17), Yield per Hectare (X18). The experiment was performed in factorial format with three factors, each at three levels, based on a randomized complete block design with three replications in three locations (g; G) and in each location for two consecutive ys (Y). The analysis of each g was analyzed in the form of factorial experiment design and the effect of location factor was analyzed in the form of factorial-split (time) composite analysis in place. In the statistical model used, time and place factor considered as random and treatment was fixed.

 Evaluation of morpho-physiological traits showed that the use of these fertilizers individually or in combination has significant positive effects on all measured traits (18 traits) at different stages of development. The simple effect of the factor of the y was significant only on some of the measured traits and the two and three-way interactions between this factor with the levels of treatment in the majority of traits were not significant; which indicates the probability that the factor of the y has no effect on the measured traits. Based on these results, the treatment combination of Fe 0.2 + Zn 0.3 + Mn 0.2 % EDTA was superior to other combinations, and traits of the number of inflorescence and number of clusters per branch and number of clusters per plant showed the best response than other measured traits. Consumption of micronutrients, especially iron, zinc and manganese, has favorable effects on yield indices, better fruit formation and fruit production per unit area, which affects photosynthetic activities and important metabolic pathways in plants, leading to produce higher amounts of primary metabolites such as higher sugar production in fruit, increase in soluble solids, also increase in growth indices such as leaf area, more yield-related traits such as number of inflorescences and number of spikes per branch and per plant, number and the dimensions of the cube are in clusters. On the other hand, these compounds help to absorb the main nutrients and play an active role in initiating metabolic processes such as cell wall development, respiration, photosynthesis, chlorophyll formation, enzymatic activities, production of growth regulators, and nitrogen fixation and reduction. Accordingly, these compounds were able to show better performance compared to the control level by accelerating the absorption of other nutrients, strengthening biochemical pathways and growth indices.

 According to these results, the application of three fertilizers of zinc, iron and manganese EDTA individually or in combinations of two or three of them, especially at high concentrations simultaneously, is superior in comparison. And the treatment composition of 0.3% zinc + 0.2% iron + 0.2% manganese EDTA and then 0.3% zinc + 0.2% iron + 0.1% manganese EDTA has more significant and positive on measured traits and therefore as fertilizer compositions are recommended in vineyards in the form of leaves.

In this study, effect of deficit irrigation from olive fruit set to ripening stage was investigated. Treatments were control (100ETc), the first one regulated deficit irrigation (RDI1); 100% ETc from fruit set to beginning of fruit ripening and 50% ETc after that to harvesting, the second one regulated deficit irrigation (RDI2); 100% ETc from fruit set to pit hardening and 50% ETc thereafter to harvest, the third one (RDI3); 100% ETc during fruit set to the pit hardening and the beginning of ripening to harvest and 50% ETc at pit hardening, and no irrigation (rainfed). Fruit and oil yield and oil quality characteristics were evaluated. Results showed that the highest yield of fruit (30.41 kg per tree) and olive oil (5.86 kg in dry weight), the least peroxide value (8.33 meq O2/kg) andK270 (0.164), alsothe highest water use efficiency for fruit and oil production (24.24 and 64.4 kg/m3 , respectively) were in RDI3. The least yield of fruit (8.96 kg per tree) and oil (18.1 kg dry weight) and the highest peroxide value (23 meq O2/kg) was observed in rainfed. Overall, results showed that RDI during fruit pit hardening could increase water use efficiency, whitout reducing fruit yield, quality and oil percentage.

Pomegranate (Punica granatum L.) is an important fruit crop of the world which native to Iran and Afghanistan. Pomegranate is produced throughout the Afghanistan. However, the most pomegranate orchard is in the south-west and the west region of Afghanistan, in the provinces of Kandahar, Helmand, Nimroz, Farah, Kapisa, Nangarhar and Herat. The major storage problems are desiccation of the fruit resulting in a brownish colored tough peel and arils, weight loss, chilling injury and fungi decay. Further, the storage temperature recommended for pomegranates has varied from 0 to 10°C from two weeks to seven months depending on the cultivar. Storing pomegranate at low temperature with packaging minimized chilling injury and maintained fruit quality. Heat treatment causes changes in fruit ripening, such as the inhibition of ethylene synthesis and action of cell wall degrading enzymes, due to changes in gene expression and protein synthesis. Pre-storage hot water treatment increases fruit quality and reduce fruit weight loss and chilling injury in pomegranate.

Fully mature, pomegranate (Punica granatum L.) fruits cv. ‘PoostNazuk Kandahar’ was harvested form Kandahar province in 2014. They were immediately transported by plane to the laboratory of Horticultural Science, Ferdowsi University of Mashhad Iran. After washing and initial measurements, half of fruits were immersed in a hot water (50 and 25°C) bath for three minutes. Hot water treatment fruits were packaged in plastic zippers and the others half were without packaging. All the treated fruits were transferred to cold storage at 5±1°C and a relative humidity of 85 to 90% for four months. Every 30 days each the physicochemical characteristics of pomegranate were evaluated. Experimental design was split factorial by completely randomized design with four replications. All analyses were performed with statistical software (JMP. 8.0, 2009).

The results demonstrated that the combination of hot water (HW) and polyethylene packaging was more effective in extending shelf life and reducing pomegranate fruit decay than the application of each treatment alone during long-term cold storage. The HW (50°C) treatment in combination with polyethylene packaging had significant effect (p< 0.01) on fruit weight loss and chilling injury index (CI) compared with the water (25°C) and without packaging during storage time. Most of fruit weight loss and CI were 37% and 24.7% that related to water (25°C) treatment and non-packaging, and the lowest were in order 1.6% and 2.2 % related to polyethylene packaging and HW (50 C°) treatments. Reduction in weight loss and CI by polyethylene packaging have been reported by other researchers [3, 4, 5, 9, 25 and 31]. HW (50°C) treatments reduced the expanding of fungi decay significant (p< 0.01) caused by use of polyethylene packaging after four months storage. This is agreement with Talaie et al [4], Artés et al [5] and Moradinezhad and Khayyat [31]. The effect of packaging on total phenolic compounds was also significant (p< 0.01). The total phenolic compounds of pomegranates showed an increase during the 120 days storage. Fruit without packaging had higher (443.25 mg/Lit) total phenolic compounds than the fruit stored in polyethylene package (332 mg/Lit), reaching a maximum accumulation, which is in agreement with the findings of other researchers [15, 24, and 38]. The HW treatment alone or in combination with packaging had no significant effect on TSS, TA and pH as compared to the water (25°C) and without packaging. At the end of storage, there was a significant increase in TSS and pH, and significant decreased in TA fruit juice after 4-month storage. Our finding is in agreement with previous reports [4, 5, 25 and 34], however was in contrast with the results of Nanda et al [33] who reported higher retention of TA in shrink film wrapped pomegranates, when compared to control fruit. One of the reasons for increase in TSS probably is decrease of fruit juice and its increase in concentration, during the storage time [1]. Rastegari et al [2] reported the increase in pH of fruit juice during storage, which is probably due to the breakdown of organic acids during the respiratory process.

Combined pre-storage treatments of HW and polyethylene package have more benefits than their individual application on maintaining quality and extending pomegranate fruit shelf life in prolonged cold storage. The pomegranate fruit cv. ‘PoostNazuk Kandahar’ could be stored for at least 20 weak under this combined treatment, effectively extending their marketing period with less decay. However, the unpackaged fruit, spoiled totally by 13 weak. Therefore, it is concluded that a combination of HW and polyethylene package treatment is a simple and low-cost method that has the ability to improve quality and postharvest life of pomegranate fruit cv. ‘PoostNazuk Kandahar’ during cold storage. However, more research is needed in this regard.

Tomato is one of the most economically important vegetable crops in many parts of the world. Improvement of yield and other essential characteristics of tomato have received more attention. Mapping quantitative trait loci could accelerate tomato breeding processes. ISSR markers were used to identify molecular makers associated with qualitative and quantitative traits in 93 landraces (from West Azarbaijan in Iran and Iğdır in Turkey) and three commercial cultivars. Association analysis using mixed linear model (MLM) identified 74 ISSR markers significantly (p

The maintenance of the quality of fresh produce is still a major challenge for the consumers. The most important qualitative attributes contributing to the marketability of fresh fruit a reappearance, color, texture, flavor, nutritional value and microbial safety. Storage conditions of product after harvest and storage duration are important factors with specific effect on products qualitativeproperties such as acidity, soluble solids materials, phenolic compounds and density. The amount of soluble solids materials is an important qualitative factor that is directly related to fruit quality and ripening.The existence of phenolic compounds, phenol absorption and changes phenol in product has caused changes in color. Shape, size, arithmetic mean diameter, geometric mean diameter, mass, volume, density, and sphericity coefficient are some of the physical properties of products that are crucial to analyze the behavior of matter in the handling.Furthermore, adequate knowledge about the physical properties of the products is of high importance in machines design, transportation and processing of product.
In this study, two types of olives, which were bitter and sweeten with 1.5%NaOHbefore the storage, were collected and their physical properties (length, width, thickness, arithmetic and geometric mean diameter, sphericity coefficient, mass, volume, density and primary moisture) were evaluated. Then, tostudy the effect of storage duration,the sweetened olives were stored at two temperatures (25℃ and 4℃temperature of the refrigerator) for 3 months,and during this period, sampling was performed at 10-dayintervals and the amount of total acidity (TA was determined by diluting each 1 ml aliquot of strawberry juice in 10 ml distilled water and then titrated to pH 8.1 using 0.1 N NaOH), total soluble solids materials (TSS was determined by a handheld refractometer device and expressed as ° Brix), phenolic compounds and the density weremeasured. The study was carried out as factorial based oncompletely randomized designwith twoindependent factors of temperature and storage time.
Results obtained for physical properties showed that the means of length, width andthickness insweet olive were 9.72, 1.34 and 1.11%respectivelyhigherthan bitter type. Penetration and absorption of NaOH and processing methods of the product can be considered among the possible causes of this increase. Linear regression relations between physical properties for sweet and bitter olives showed that mass and volume of fruit areestimated accurately according to the main dimensions. The results of data variance analysis also showed thatdensity and soluble solids materialswere significantly affected by themain and interaction effects of the twofactors at 1% probability level. Moreover, the main effect of storage time on total acidity and phenolic compoundswassignificant at 5% and 1% levels, respectively. With increasing storage time, density of sweet olive increased and soluble solids materials and phenolic compounds decreased. Acidity changes of olive during storage fluctuated, and an increase was found in the values of density and soluble solids materials along with theincrease of storage temperature from 4℃ to 25℃.With respect to density, the third month of storage showedhigherincrease compared toother months, and maximum value was reported for sweet olive in temperature of 25℃ and 19thday. Increase ofstorage duration resulted in the reduction of moisture content,whichin turns leads to the reductionof product volume and increase of density. The reductionfound in acidity in the second and third months of storage resultedfrom maturation and ripening processes of the fruit. Organic acids are a source of energy,which are consumed in the time ofmetabolism increaseand fruit ripening.Decreasein phenolic compounds also occurs as the result ofphenol penetration from olive flesh into the water - salt solution.
Results of this study showed that length, width, thickness, mass and volume of sweet olive weregreaterthan bitter type, but,by contrast,sphericity coefficient was higher in bitter olive. Moreover, storage time, increase caused an increase in thedensity of sweet olive and decrease insoluble solids materials and phenolic compounds.There was fluctuation inacidity during different storage times. An increase was found in the values of density and soluble solids materials along with the increase in storage temperature from 4℃ to 25℃.

In order to investigate the influence of humic acid spraying on trees on shelf life and to maintenance of quantitative and qualitative characteristics of ‘Granny Smith’ apple, an experiment based on completely randomized block design was conducted in khoramdareh postharvest physiology laboratory of University of Zanjan. The humic acid spraying was conducted in four concentrations of 0 (distilled water), 5, 10 and 15 mg l-1 on 8 year-old ‘Granny Smith’apple trees grafted on MM106 rootstock. Spraying was conducted 2, 4 and 8 weeks after full bloom stage. Fruits of trees treated stored in 0±0.5°C with 90±5% relative humidity for six months. Fruit weight loss, fruit firmness, pH, total soluble solid (TSS), titrable acid (TA), total sugar (TS) and ascorbic acid content (vitamin C) were measured every two months. The results showed that, during the storage, fruit weight, fruit firmness, TA and ascorbic acid decreased. The maximum and minimum amont was belong to 10 and 15 mg l-1 humic acid and control treatment in the third stage of sampling (sixth months). Meanwhile, total soluble solid, pH and TA increased in the storage. According to the obtained results, it can be concluded that humic acid spraying had influence on shelf life and quantity and quality characteristics of ‘Granny Smith’ apple during storage. Therefore, to maintain postharvest quality of ‘Granny Smith’ apple spraying of humic acid with concentrations of 10 and 15 mg l-1 on trees is recommended.

The effect of Ca، Zn and B spray application on preharvest fruit drop، sugars، calcium، zinc، and boron concentrations and as well on some physicochemical fruit properties of five commercial Asian pear cultivars (‘KS’7، ‘KS’8، ‘KS’11، ‘KS’12 and ‘KS’14) was investigated under Tehran Province،s environmental conditions. Trees were sprayed one month past fruit set until harvest within two week intervals with Ca، Zn، B and as well with their mixtures at 5% concentrations. Fruit drops were recorded from treatments، start untill harvest. At the time of fruit harvest، fruit sugar and mineral contents were determined using HPLC and ICP، respectively. Results revealed that Ca، Zn and B applications decreased preharvest fruit drop in a way that a combination of Ca، Zn، and B applications rendered a 6. 3% fruit drop in comparison with 17. 3% occurring in control. Throughout the research، fructose was found out as the dominant sugar followed by glucose، sorbitol and sucrose in the studied cultivars. Spray applications of Ca، Zn and B increased the fruits، fructose، glucose، sorbitol and sucrose contents in all the studied cultivars (1-2. 5، 1-2. 1، 2-3. 7 and 0. 7-2. 2 % fresh weight، respectively). In addition، total soluble solids increased by 1-2 ºBrix total sugars (1-2 % of fresh weight)، total acidity (0. 07-0. 12 mg 100-1g) and dry weight (1-1. 5g) of fruits in all cultivars. Spray of Ca increased fruit firmness (1-2 N varied with cultivar). Spray of Ca، Zn and B applications increased Ca، Zn and B mineral contents of both leaves and fruit.