Yonus Mohammad Nezhad; Majid Basirat; Hossein HajiAbaee; Benjamin Torabi
Abstract
In the fields around Golestan dam, crop rotation is not performed, putting the soil fertility at risk. This experiment aims at evaluating the nutritional status of the region’s soils and determining the need for fertilizer with emphasis on macronutrients. The fertilizer requirement of these soils ...
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In the fields around Golestan dam, crop rotation is not performed, putting the soil fertility at risk. This experiment aims at evaluating the nutritional status of the region’s soils and determining the need for fertilizer with emphasis on macronutrients. The fertilizer requirement of these soils in 2017-2018 has been determined, using the QUEFTS model. At first, 30 fields in the Golestan dam region, irrigated by the dam itself, have been chosen. In each field, a small section has been selected as a non-fertilized one. All agronomic practices have been done in accordance with conventional farmers' method. From each field (fertilized and non-fertilized), five one-meter squared quadrats have been used to cut off the crop and the grain yield and non-grain yield, and measure its N, P, and K concentration. Results reveal that the mean value of N, P, and K uptake by shoots have been 54, 19.5, and 98 kg/ha, respectively, with the average grain yield being 4150 kg/ha in farmers' field. For 1000 kg of grain production per hectare, one requires 13, 4.5, and 22 kg of N, P, and K, respectively. Therefore, according to the proper validation results of the QUEFTS model, it is recommended to apply 325 kg/ha urea fertilizer, 195 kg/ha triple super phosphate fertilizer, and 60 kg/ha potassium sulfate fertilizer to produce about 5000 kg/ha wheat grain in this area.
Mohsen Seilsepour; Ahmad Golchin; Mahmoud Reza Roozban
Abstract
A greenhouse experiment was carried out to evaluate the effects of salinity stress on growth and macroelements contents of two olive varieties in soilless culture medium. In the research, one-year old saplings of two olive varieties, ‘Zard’ and ‘Mission’, were subjected to different ...
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A greenhouse experiment was carried out to evaluate the effects of salinity stress on growth and macroelements contents of two olive varieties in soilless culture medium. In the research, one-year old saplings of two olive varieties, ‘Zard’ and ‘Mission’, were subjected to different salinity levels induced by NaCl including 0, 4, 8, 12 and 16 dS/m-1 for 5 months. Based on the results, total dry weights of the varieties were decreased at 16 dSm-1 compared to control up to 63 and 85% at ‘Mission’ and ‘Zard’, respectively. Also, a 25% reduction in total dry weight was observed under salinities of 7 and 3.6 dSm-1 for ‘Mission’ and ‘Zard’, respectively. Salinity was decreased the concentrations of macronutrients and increased the concentrations of Na and Cl in roots and leveas of the both varieties. Compared to control, Na and Cl concentrations in leaves and roots was increased under salinity of 16 dS/m-1 at 1660 and 679% for Na and 1069 and 506% for Cl. In all salinity levels, Na and Cl concentrations in the leaves and roots of 'Zard' variety were more than that of 'Mission'. Thesa data demonstrated that ‘Mission’ has a more salinity tolerance than ‘Zard’, and could be used as a salt-tolerant variety for cultivation under salinity conditions. The defence mechanisms of ‘Mission’ are restricting in absorbtion and translocation of Na to aerial parts and accumulate a proper concentration of K in Leaves.
Ali Momenpour; Davood Bakhshi; Ali Imani; Hamed Rezaie
Abstract
The types of scion-rootstock compound and level of salinity affect on growth characteristics and concentration of nutrition elements of almond leaves and roots. In order to evaluate the effect of salinity stress on vegetative traits and concentration of nutrition elements of leaves and roots almond genotypes, ...
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The types of scion-rootstock compound and level of salinity affect on growth characteristics and concentration of nutrition elements of almond leaves and roots. In order to evaluate the effect of salinity stress on vegetative traits and concentration of nutrition elements of leaves and roots almond genotypes, a experiment was carried out with two factors; cultivar in four levels including ‘Shahrood 12’, ‘Touno’, ‘1-16’ budded on GF677 rootstock and GF677 and water salinity in five levels including zero, 1.2, 2.4, 3.6 and 4.8 g/l of sodium chloride salt (with the electrical conductivity of 0.5, 2.5, 4.9, 7.3 and 9.8 ds/m, respectively). The result showed that with increasing salinity concentration, branch height, branch diameter, and number of produced leaves and percentage of green leaves have been reduced but percentage of necrotic leaves and percentage of downfall leave were increased. The result showed that in the total genotypes studied, the highest rate of Na+ (2.12%), Cl- (4.94%), ratio Na+/K+ (2.03%), ratio Na+/Ca++ (1.92%), ratio Na+/Mg++ (6.81%), ratio Na+/P (14.07%), and the lowest rate of Ca++ (1.06%), Mg++ (0.33%), P (0.146%), Zn++ (32.7 ppm), Cu++ (9.33 ppm), in leaves was observed in treatment 9.8 ds/m of NaCl. The result showed that type of scion was affected in obstruction of Na+ absorption by the roots and their transported to leaves. In the total level of salinity studied, ‘Shahrood 12’ was the lowest rate of Na+, Cl-, ratio Na+/K+, ratio Na+/Ca++, ratio Na+/Mg++, ratio Na+/P and the highest ratio Cl-/ Na+. Also, this cultivar can tolerate high level of salinity (7.3 ds/m), by increasing content of K+ (1.65%),Cu++ (9.62 ppm), Fe++ (22.30 ppm), Zn++ (50.45 ppm) more than other genotypes studied in this research, to deal with the devastating effects of Na+. Overall, ‘Shahrood 12’ was recognized as the most tolerant cultivar to salinity stress.