Ahmad Daneshkhah; Mahmoud Ghasemi Nejad raeini; Mohammad Amin Asoodar; Afshin Marzban; Mokhtar Heidari
Abstract
AbstractIntroduction In recent decades, population growth has led to changes in dietary behavior and a significant increase in global demand for food production, which has led to the promotion of heavy use of agricultural land. water shortage in arid and semi-arid regions is one of the most important ...
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AbstractIntroduction In recent decades, population growth has led to changes in dietary behavior and a significant increase in global demand for food production, which has led to the promotion of heavy use of agricultural land. water shortage in arid and semi-arid regions is one of the most important factor that affect crops production. The use of different conservation tillage methods such as minimum tillage and the use of organic and inorganic mulch as methods used in sustainable agriculture, can reduce water and energy consumption in an agricultural system. Soil water affects plant growth and development. So that even a small change in soil water content can significantly change the productivity of crops. Soil cover or mulch is one of the management strategies to increase water use efficiency of agricultural products.Materials and Methods In this study, research was conducted to investigate the effect of conservation tillage methods and plasticulture patterns on water use efficiency and strawberry crop yield in 1398. The water use efficiency was calculated to assess the effects of tillage and plastic covers in the field. . The experiment was conducted using of factorial design in the form of randomized complete blocks with three replications. The plots included two types of tillage systems (conventional and conservation) and three methods of plastic cover (planting under plastic, over plastic and without plastic coverage). This experiment was performed in 18 plots with dimensions of 0.8×15 meters. 3 rows were planted in each plot. The distance between sub-plots was 75 cm as a ridge, the distance between main plots was 1 and a half meters and the distance between replicates was 2 meters. Water use efficiency (WUE) is one of the most important indicators for measuring agricultural water productivity. This index is actually the ratio of the amount of product produced per amount of water consumed (evaporation-transpiration) of the plant. In this definition, instead of evaporating and transpiration of the plant, the amount of water used in the field can be replaced and the amount of crop production per unit volume of water used in irrigation can be obtained. The higher this ratio, the better the water consumption.Results and Discussion The two factors of tillage and planting pattern only affected soil moisture content at a depth of 0-10 cm and no significant effect was observed between different treatments at a depth of 10-20 cm. Minimum tillage in the pre-irrigation and post-irrigation stages has the highest moisture content. Conventional tillage disturbs the soil more than minimum tillage, increasing pores and unevenness of the soil surface, thereby increasing surface evaporation. Planting pattern had the highest moisture content and over plastic planting pattern had the lowest moisture content. Plastic cover is a barrier that prevents soil water from evaporating and keeps the root zone moisture regime at more stable levels, thus reducing the need for irrigation and preventing physiological disorders related to nutrients and water. There is no significant difference between tillage factor in two levels of conventional and low tillage and only planting pattern at 1% level has a significant difference. Different planting patterns significantly affected strawberry yield. According to the comparison of the average, the highest yield was related to the planting pattern on plastic and the lowest was obtained on the planting pattern without plastic. Since the yield of strawberries in different tillage methods was not significantly different and in this study the same amount of water was used in different methods. Therefore, tillage methods had no significant effect on strawberry water productivity.Conclusion The data was shown that the use of conservation tillage and plasticulture increased soil moisture retention by 22% which is due to the prevention of evaporation of soil moisture by Plastic mulch and Plant residue cover and less soil disturbance in conservation tillage. Conservation tillage has no significant effect on strawberry yield due to the slow trend in changing soil properties, but plastic mulch increased strawberry yield by 31.71% due to the increase in soil moisture retention. Since the type of tillage did not have a significant effect on strawberry yield in this study, therefore, tillage does not have a significant effect on water use efficiency, but different planting patterns, due to affecting yield, significantly increase water use efficiency here.
Fatemeh Moradi Ganjeh; Rasoul Meamar Dastjerdi; Mokhtar heidari; Mohammad Hadi Movahednejad
Abstract
Introduction Citrus are one of the major agricultural production available in the world and it is one of the popular fruits in the diet. The most well-known varieties of citrus fruits include oranges, lemons, grapefruits and tangerines. Cultivation of sweet lemon requires specific climate situation that ...
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Introduction Citrus are one of the major agricultural production available in the world and it is one of the popular fruits in the diet. The most well-known varieties of citrus fruits include oranges, lemons, grapefruits and tangerines. Cultivation of sweet lemon requires specific climate situation that it is found in many region of Iran. However, the high quality ones are in Jahrom, Ghsre Shirin, Dezfool, Jiroft and the Sorth of Iran. Two major limitation of long-term storage for citrus fruits are decay caused by pathogens, especially fungi, skin fruit damage and water loss, which can cause wrinkles and reduce product marketability and consumer acceptability. Edible coatings are one of the most effective methods to maintaining the fruit quality. Today edible coatings can preserve citrus quality and provide attractive approach to satisfactory performance. Chitosan is used for film or edible coatings to extend the shelf life of foods such as fruits, meat and fish and foods. The results of several studies indicate the effective role of chitosan in controlling fruit during storage. Wax in the fruit is used to prevent moisture loss and wrinkle of the fruit and also to maintain the appearance of the product and its marketability. So, the final goal of this study is investigate the effect of edible coatings (chitosan-clay Nano composite, Wax coatings and olive oil) on some quality attributes of sweet lemon during shelf life storage.Materials and Methods Sweet lemon's fruits (216 N.) were harvested randomly from a citrus orchard in Dezfool, Iran. The samples immediately sent into the laboratory for storage after necessary treatments. All fruits were disinfected by immersion in 4% chlorox for 3 minutes and then dried. Chitosan with low molecular weight (43 KD) was bought from Sigma Aldrich Company. Clay was purchased from Sefid Sang Aligoodarz Company in Iran and wax coating was provided from Pooshesh Hayat sabz company in Iran. The chitosan-clay coating was prepared by dissolving a mixture of chitosan (3w/v% to solution), clay (5, 10 and 15% wt to chitosan) and glycerol (10v/w% to chitosan) and tween 80(5% v/w to chitosan) in acid lactic solution (2%). Nano structure of chitosan-clay nano-composite was approved by XRD analysis. The chemical parameters of fruit juice such as TSS (%), pH(%) and TA (%) of lemon juice were measured. TSS was determined by digital refractometer (model MA882, made in Japan). pH was measured by pHmeter ( portable p-755 model) and TA was determined by AOAC standard method. The experiment was performed at three levels of chitosan-clay nanocomposite, olive oil, Carnoba wax and uncoated samples during 12 days shelf life storage. The experimental design was factorial based on completely randomized design with three replications. Limon samples were maintained at ambient temperature of 25 ℃ and relative humidity of 80-85%. Chemical characteristics (pH, citric acid, fruit juice TSS, vitamin C) and mechanical characteristics (weight loss percentage, sphericity coefficient, maximum shear force, maximum fracture force and maximum tensile strength of the fruit skin) were measured during storage.Results and Discussion The results of experiments showed that the trend of changes in vitamin C content decreased during storage. But this decrease was slower in the different percentages of chitosan-clay, olive oil coating and carnoba wax than in the control samples.The results showed the significant differences at 1% and 5% levels between different coatings at maximum fracture force, percent weight loss and pH. In addition, the effect of storage times on TSS, pH and maximum fracture force was significant. The lowest and highest percentage of weight loss for uncoated samples and olive oil coating were 12.3% and 10.23%, respectively. Results showed that the coated fruits had the better performance in preserving the quality of properties than the uncoated samples and 5% chitosan-clay nanocomposite coatings were higher performance than the other coatings.Conclusion In this study, the effect of chitosan-clay nanocomposite, olive oil, Carnoba wax and uncoated samples during 12 days shelf life storage on Chemical characteristics (pH, citric acid, fruit juice TSS, vitamin C) and mechanical characteristics (weight loss percentage, sphericity coefficient, maximum shear force, maximum fracture force and maximum tensile strength of the fruit skin) were investigated. The results of this study showed that 5% chitosan-clay nanocomposite coatings were higher performance than the other coatings.
