The Effect of Potassium and Manure Application on Concentration of Macro Elements on Wheat under Different Water Stresses

In order to study the effect of potassium and manure fertilizer on yield and concentration of macro elements in leaf and grain of wheat (N-81-18 cultivar) under water stress, a pot experiment was conducted in split plot based on randomized complete design with four replications in 2009-2010 crop years. The main factor was inclusive irrigation after depletion of 75, 50 and 25 percent of available water, and the subsidiary factor was inclusive potassium sulfate in three levels (0, 300 and 600 kg/ha) as well as manure fertilizer in three levels (0, 20 and 40 ton/ha). Results indicated that irrigation treatment had a significant effect on grain yield and elements of nitrogen, phosphorous and potassium in leaf and grain at p<0.01 and the greatest amount of elements except for the phosphorous of grain was observed in irrigation treatment after depletion of 75% available water. Phosphorous in leaf and grain increased with the consumption of manure fertilizer and the most amount of phosphorous of grain was obtained in irrigation treatment after depletion of 50% available water and application of 40 ton ha-1 manure fertilizer and the greatest amount of phosphorous of leaf was observed with consumption of 20 and 40 tons ha-1of manure fertilizer. The maximum amount of grain yield was achieved in irrigation treatment after depletion of 25% available water and usage of 40 ton ha-1manure fertilizer. Grain potassium was increased with the consumption of 300 and 600 kg/ha-1 potassium sulfate.