Sherif, A. E. A. ; Samia M. A. ElKhalawy and E. A. Hegab( 2017). Impact of Nitrogen and Cobalt Rates on Faba Bean Crop Grown on Clayey SoilJ.Soil Sci. and Agric. Eng., Mansoura Univ., Vol. 8 (9): 459 - 465, 2017
Abstract: Two field experiments were carried out in the two-successive winter seasons of 2014-2015 and 2015-2016 on faba bean (Vicia faba L.,) at El-Gemmaiza Agricultural Research Station, El-Gharbia Governorate, Egypt, located at (Lat. 30؛ 48´ 752" and Long. 31؛ 81 025"). as sake of studying study the influence of nitrogen as ammonium sulphate (20.5% N) at rates of (0.0, 7.5, 10.0 and 15.0 kg N fed-1) and foliar spray of cobalt at rates of (0.0, 0.5 and 1.0 mg L-1) as cobalt sulphate on yield, yield components, nutrients status. The statistical analysis of this experiment was randomized complete block design for combined two seasons.The results indicated that, faba bean yield (grains, straw and 100 grains weight) were significantly increased with the application of N compared to control. The highest significantly increases in grain, straw and roots yields of faba bean were obtained at accompanied treatments of 15.0 kg N fed-1 with two rates of cobalt (0.5 and 1.0 mg L-1). Foliar spray with cobalt at a rate of 1 mg L-1 gave the highest yield and yield components. Data also show that, combined treatments of N and cobalt at all rates under study were significantly increased grain, straw and roots yields. The highest increases were obtained with applied rate of 15.0 kg N fed-1 combined with 1.0 mg L-1 cobalt as foliar spray. Additions of three rates of N were significantly increased N, P, K, Fe, Mn, Zn, Cu and Co contents of grains, straw, and roots. Also, two rates of cobalt were significantly increased all nutrients in grain, straw, and roots. The highest increases also, were obtained at a rate of 15.0 Kg N fed-1 accompanied with 1.0 mg L-1 cobalt. Data, obtained also showed that the interaction between N and Co were increased N, P, K, Fe, Mn, Zn, Cu and Co, in grains, straw and roots especially at rate of 15.0 Kg N fed-1 combined with 1.0 mg L-1 cobalt. The addition of different levels of nitrogen and cobalt led to a significant increase in the availability of (N, P, K and Co) in the soil. The highest increase was may be due to the addition of 15.0 kg N fed-1 with cobalt at a concentration of 1.0 mg L-1
Keywords: (faba bean, cobalt, Nitrogen rates, nutrients status, productivity , clayey soil.)
