Effect of different nitrogen levels on some soil characteristics and chemical composition of wheat plant (Triticum aestivium L.)

Abstract

A field experiment was carried out at Faculty of Agriculture, Al-Azhar Univ., Nasr City, Cairo, Egypt, to investigate the effect of different nitrogen levels on some soil characteristics and chemical composition of wheat crop. To achieve this task two varietiesGemmeiza7 and Gemmeiza of wheat plant were studied under five nitrogen levels (i.e. 0, 65, 130, 195 and 260 kg /fed) were applied as urea (46% N) as nitrogen fertilizer. All the plots were fertilized with super phosphate and K- sulfate according to the general recommendation dose of Ministry of Agriculture. Results indicated that soil organic matter, EC and soil porosity were increased with increasing the rate of nitrogen application. But pH and the bulk density were decreased significantly. Application of 260 kg N/fed gave the highest values of NP and K contents in straw and grain compared to control treatment.The percentages of N and K increased significantly by increasing Nitrogen rate up to 260 kg N/fed. But 195 Kg/fed gave the highest values of p in grains in the two cultivars. On the other hand, chemical composition (crude protein, total carbohydrates, lipids, moisture, ash and fiber) of two wheat varieties was affected by the addition of nitrogen rates. The crude protein percentage was increased significantly by increasing the rate of nitrogen application. Also the total number band of Protein electrophoretic increased with increasing the nitrogen levels compared with control. In most cases lipids were decreased with increasing the rate of nitrogen. But fiber was increased. Total carbohydrate was significantly decreased with increasing of nitrogen rate. Also the highest value of moisture percentage was observed in 65Kg/fed treatment in the two cultivars. Generally, Gemmeiza 7 was higher than Gemmeiza 9 of Protein percentage at the same dose of nitrogen levels.