Collectively, the challenges aim to accelerate the development of innovative fertilizer product technologies and to increase the use of existing enhanced efficiency fertilizers sources (EEFS) like slow release fertilizers (SRF) as an example for increasing crop yields and reducing environmental impacts to air, land and water.Two field experiments were carried out at Experimental Farm of Tag El-Ezz, Agricultural Research Station (30o 59\ N latitude, 31o 58\ E longitude´), Agriculture Research Center (ARC), Dakahlia Governorate, Egypt. Completely randomized blocks design (CRBD) with three replicates was used during the two winter and summer successive growing seasons 2020/21 and 2021 to study the effect of three different slow release nitrogen fertilizer (SRNF) sources 1- sulfur coated urea (SCU), 2- urea formaldehyde (UF) and 3- cement coated urea (CCU) with different fertilization rates (100,125 and 150 % from the recommended dose) comparing with conventional urea (CU) under recommended fertilization rate for wheat and corn crops respectively (75 and 120 kg N fed-1) on growth, yield and its components of wheat (Triticum aestavium L.) cv. Misr1 during the winter season. As well as studying the residual effect of (SRNFs) with half additional application does of conventional urea to each plot on maize (Zea mays L.) var. (Tri Cross 360) growth, yield and its components. Available soil N in the experimental plots was determined during the growing seasons along the two experiments.
The obtained results indicated the ability to use new age technologiesas enhanced efficiency fertilizers (EEFS) like slow release fertilizers (SRFs) to sustain crops yield and maintain environment quality.
SRNFs applications gave the highest values of vegetative growth, yield and its components of wheat plant compared to conventional urea. Raising rate of N fertilizer caused an increase in all studied parameters.
SCU using at 100% fertilization rate was the superior SRNF using at the same rate where it increased ChllC a+b and BY by 31.23 and 19.95%, respectively, as well as it gave the highest grain nutrients concentration and protein content by 2.35% for N; 0.289% for P; 1.38% for K and 13.51% for protein comparing with CU using at 100% fertilization rate.
The highest residual N (mg kg-1) in the soil after wheat harvesting was recorded with cement coated urea (CCU) and the same trend continuous to maize post harvesting. Thus the residual of CCU using at 100% fertilization rate + 50% CU increased maize ChllC a+b and BY by 36.40 % and 7.27%, respectively as well as it gave the highest values of maize grain content from N (2.09%), P (0.134%), K (1.46%) and oil content (5.20%) comparing with CU using at 100% fertilization rate.
Economically, we advised farmer using SCU at 100% fertilization rate for one crop and using CCU at 100% +50 % CU recommended fertilization rates for cropping sequence.