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Introduction Grape (Vitis vinifera L.) is one of the most important fruits cultivated in many areas with different climates all over the world. Grape, which is rich in antioxidants, flavonoids, anthocyanins and phenolic acids, is highly regarded in terms of economic value. Salicylic acid is one of the compounds which have been used in recent years for improving the physicochemical properties of many fruits. The application of salicylic acid increases the shelf life of crops by inhibiting ethylene production and respiration, as well as by reducing the activity of some enzymes which are responsible for softening the cell wall. Furthermore, salicylic acid results in the enhancement of phenolic compound production by increasing the activity of some enzymes such as phenylalanine ammonia-lyase.Materials and Methods The present study was conducted in 2014 on 13-year-old Shahroodi grapes that were grown using a head-training system with a spacing of 2m × 2m in "Shahrood" County, Semnan Province. A total of 60 grapevines with uniform age and growth characteristics were selected for the experiment. Salicylic acid was obtained from Merck and solutions were prepared using a small amount of organic solvent and surfactant to reduce the surface tension of the solutions. For the purpose, the Salicylic acid powder was dissolved in a few drops of ethanol and a few drops of Tween 20 for improving solution penetration to the plants, The solution was prepared at concentrations of 0 (control), 1, 2, 3 mM. Then the plants were sprayed two weeks after the fruit set stage (when berries were at the pea-sized stage with a diameter of 4 to 5 mm). The experimental design used in this experiment was a randomized complete block design (RCBD) with three replications. After harvesting and transporting of fruits to the laboratory, different characteristics were measured:Chlorophyll and carotenoid ContentChlorophyll a, b, and total Chlorophyll and carotenoid content measured according to Arnon (1967) method in grape leaves. The extraction steps were carried out with full precision to minimize contact with heat and light. In order to stabilize the pigments, the samples taken from the central part of the mature leaves were immediately ground in liquid nitrogen. The samples were vortexed two times with an interval of one minute and stored for 1.5 hours at a temperature of 4 degrees Celsius in order to dissolve the pigments in cold acetone solvent. After that, they were centrifuged for 15 minutes at a speed of 6000 rpm. The supernatant after centrifugation of the samples was used to measure chlorophyll and total carotenoids. The absorbance of the samples was read at three wavelengths of 470, 645, and 663 nm using a Shimadzu UV (160) spectrophotometer. Using the absorbance of the samples in these three wavelengths and the equations below, the amounts of chlorophyll a, chlorophyll b, total chlorophyll and total carotenoids were calculated in terms of milligrams per gram of tissue sample weight.Fruit characteristics Fruit characteristics such as fruit yield, fruit firmness (with magnets-Taylor device), sugar and acid content, and content of phenolic compounds were also measured. The fruit tissue firmness was measured using a firmness tester (model FDKA 32, Wagner) and expressed in Newtons per square centimeter. The characteristics of soluble solids (TSS) were expressed using a handheld refractometer (Ataga, Japan) and expressed in terms of Brix, the pH of the extract was measured using a digital pH meter (Sartorius PP-20, Germany). Titratable acidity or TA was done through the titration of the extract using 0.1 normal sodium until pH 1.8-2.8 and its results were reported using the following formula and under the title of tartaric acid percentage.Total phenol content The amount of total phenol was measured by Folin-Ciocalteu method and spectrophotometry. The absorbance of the reaction mixture was measured after 120 minutes of storage in the absence of light at a wavelength of 765 nm using a Shimadzu UV spectrophotometer (160). The amount of total phenol was expressed from the standard curve in terms of mg of gallic acid per 100 grams of extract in three replicates for each sample and standard.Total flavonoid The amount of total flavonoid was measured by aluminum chloride calorimetric method. In this experiment, 50 microliters of methanolic extract from the flesh and fruit skin were combined with 10 microliters of 10% aluminum chloride and 10 microliters of 1 M potassium acetate. Then, 280 microliters of double distilled water were added to the mixture. After the samples were mixed, they were left at room temperature for 40 minutes. The absorbance of the reaction mixture was measured at a wavelength of 415 nm using a Shimadzu UV spectrophotometer (160) in three replicates. A blank containing double distilled water was used for comparison. The amount of total flavonoids was determined based on the standard curve of quercetin and the results were expressed in micrograms of quercetin per gram of fruit skin and flesh weight.Total anthocyanin The amount of total anthocyanin was measured using the difference in pH method. In this method, the absorbance was measured using a spectrophotometer at wavelengths of 520 and 700 nm along with potassium chloride and sodium acetate buffers with different pH values of 1 and 4.5.Results The results of the data analysis of variance showed that the application of salicylic acid resulted in significant differences in the measured characteristics. Therefore, the use of this compound improved the physical and biochemical quality of the treated grape clusters.Comparison of treatments means showed that using 2 mM salicylic acid brought about a significant effect on the amount of chlorophyll (a, b and total) and carotenoids compared to other treatments, especially control. Salicylic acid application caused a reduction in pH and soluble solids, and an increase in firmness, 100-berry weight and yield. The results of the study indicated a significant increase in organic acids and a decrease in reducing sugars in the grape clusters treated with salicylic acid. The highest amount of tartaric acid was found in the treatment with 2 mM salicylic acid, with an average of 0.66, while the control treatment had the lowest amount of tartaric acid, with an average of 0.52. This suggests that the use of salicylic acid led to a reduction in transpiration and consumption of organic acids. In terms of reducing sugars, the highest and lowest amounts were observed in the control treatment (14%/74) and the treatment with 2 mM salicylic acid (13%/60), respectively. Increasing the concentration of salicylic acid up to 2 mM resulted in the enhancement of anthocyanins and phenolic compounds contents, but higher concentrations (more than 2 mM) reduced the amounts of these compounds in treated fruits.Conclusion Pre-harvest use of salicylic acid could have a positive effect on the improvement of qualitative and quantitative characteristics of grape cv. Shahroodi. However, further comprehensive studies are needed to be conducted to recommend this compound to the growers of fruit trees.

Due to limited access to water, it is necessary to determine the comparative advantage of crops and horticultural products in different parts of the province and identify products that lack the desired productivity. Then, find ways to improve water productivity or replace products with higher comparative advantage with low-yield products. Based on this, the crop and economic productivity index of the province's agricultural and horticultural products under surface irrigation systems was determined. Based on the results of gross economic productivity of horticultural products, pistachio with 48690 Rials per cubic meter had the highest economic productivity, and grapes with 30220 Rials per cubic meter (62% of pistachios) was in second place. In addition, water quality for pistachios can never be generalized for grapes and other crops, and this is a tremendous advantage for pistachios that low-quality water resources can also be used. The lowest gross economic productivity of water for barley, alfalfa, and wheat is equal to 3790, 3990, and 4570 Rials per cubic meter, respectively. The study of fodder corn shows that the net profit from the cultivation of this crop in the surface irrigation system is equal to 51.78 million Rials per hectare and its net profit in the strip drip irrigation system (tape) is equal to 110.87 million Rials, which it has a 2.14-fold increase compared to the conventional irrigation method. The comparative advantage of horticultural products was higher than that of crops, and the replacement and development of orchards instead of some crops is recommended as a solution. In addition, solutions that can be recommended to improve the productivity index include the use of a drip irrigation system (tape) for crops (fodder corn, tomatoes, summer crops, and potatoes) and the use of drip irrigation (normal, subsurface, and subsurface modified drip) for horticultural products. Examination of practical experiences of using tape irrigation system for wheat and barley showed that this method has not improved the agricultural and economic productivity index, which indicates the lack of comparative advantage of wheat and barley cultivation in Semnan Province even with tape irrigation system.

This study was done to evaluate the effect of pre-harvest foliar application with chitosan (500 and 1000 mg L -1 ), Nano-chitosan (250 and 500 mg L -1 ), and chitosan/ZnO nanocomposite (250 and 500 mg L -1 ) coatings on the quality and shelf life of fresh pistachios of "Akbari" and "Ahmad Aghaei" cultivars during storage. The results showed that 250 and 500 mg L -1 of chitosan/ZnO coatings significantly affected the shelf life of pistachios up to 35 and 40 days, respectively; in addition, chitosan/ZnO nanocomposite in both cultivars reduced weight loss, aflatoxin contamination, decay, polyphenol oxidase and glutathione-peroxidase enzymes, peroxide value, free fatty acids, and improve firmness, sensory properties, protein, oil content, carbohydrate, antioxidant properties, anthocyanin, phenol, and flavonoid. These results indicated that using chitosan/ZnO (250 and 500 mg L -1 ) is a promising efficient, safe, and environmentally friendly method for preserving the quality of fresh pistachios. It reduces hull browning and minimizes post-harvest losses., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Fresh pistachios are rich in dietary fiber, minerals and unsaturated fatty acids, but they have a short shelf life. This investigation examined the effect of pre-harvest foliar application with chitosan (500 and 1000 mg. L -1 ), nano-chitosan (250 and 500 mg. L -1 ), and chitosan/TiO2 nanocomposite (250 and 500 mg. L -1 ) coating films on the postharvest physiology and storage of fresh pistachios (Pistacia vera cvs. Akbari and Ahmad Aghaei) cultivar during storage at 4 ± 0.5 °C. It was found that, fresh pistachios' shelf life could by increased by up to 30 days by the use of chitosan/TiO2 nanocomposite coating for foliar application. The decay index of the composite coated fruits was 4-6 % lower than that of the control group, and after 50-60 days the bacterial contamination appeared in cultivars; respectively. The nanocomposite treatments reduced the fruits weight between 30 and 40 %, which was 15 % higher that of than uncoated fruits. The pre-harvest application of chitosan/TiO2 coating reduced microbial contamination, weight loss, phenylalanine ammonialyase (PAL) activity and saturated fatty acids, and increased unsaturated fatty acids, antioxidant properties, sensory properties, essential minerals, superoxide dismutase (SOD), quality indicators and shelf life. These results demonstrated that the chitosan/TiO2 (250 and 500 mg. L -1 ) coating film effectively preserved the nutrient composition, sensory quality, nutritional value, antioxidant capacity and shelf life of fresh pistachio., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)