A field study was carried out in the Agricultural Research and Experimental Center, Faculty of Agriculture at Moshtohor, Kalubia Governorate, Benha University, during 2006/07 and 2007/08 seasons. The aim was to assess influence of nitrogen (N) fertilization, biogas sludge (BS) manure and bio-fertilizer (BF) on grain nitrogen uptake (Nup) and yield of wheat. Three N levels (0, 40 and 80 kg N/fed), two biogas sludge levels (0, 3 tons/fed) and two bio-fertilizer treatments (with and without) were used in split-spilt plot design with four replications. The results indicated that the highest N level (80 kg N/fed) was more effective for increasing all studied traits i.e. number of tillers and spikes/m2, plant height, spike length, number of spikelets and grains/spike; 1000-grain weight, grain yield/fed., grain N content , grain protein content (GPC%) and grain N uptake. The application of 40 and 80 kg N /fed increased the grain yield over the control treatment by 45.4 and 65.0% in 2006/07 season, 40.0 and 66.5% in 2007/08 season, being 42.6 and 65.8% in the combined analysis. Application 3 tons biogas sludge manure/fed significantly increased grain yield, its components and grain N uptake. Grain yield increased due to adding 3 tons/fed over the check treatment by 10.2, 18.7 and 14.5 % in the 1st, 2nd seasons and combined analysis, respectively. Bio-fertilization significantly increased number of tillers and spikes/m2, plant height, spike length, 1000- grain weight, grain yield/fed, N%, GPC% and grain N uptake compared without bio-fertilization in both seasons and combined analysis. Significant interaction effects (in combined analysis) were found between nitrogen levels and biogas sludge manure on spike length and number of tillers/m2. Also, interaction was found between nitrogen levels and bio-fertilizer on grain nitrogen uptake as well as between biogas sludge manure and bio-fertilizer on number of tillers /m2.Whereas, no significant second order interaction effect was found for any of the studied traits. |