EFFECT OF BIO AND ORGANIC N FERTILIZER AS A PARTIAL SUBSTITUTE FOR MINERAL-N FERTILIZER ON YIELD OF PEANUT (Arachis hypogaea L.)

Abstract

Egypt, located at lat. 30° 35' 30" N, long. 32° 14' 50" E. during two successive summer seasons of 2013 and 2014, to study the effect of partial replacement of mineral N fertilizer by organic or bio-fertilizers on soil microbial activities, some seed macro nutrients content , growth characters, yield and yield components of peanut. Results of this study showed that inoculation with cyanobacteria enhances the soil biological activity in terms of increasing the total bacterial, total cyanobacterial counts, CO 2 evolution, dehydrogenase and nitrogenase activities. Combined inoculation of cyanobacteria at 20 or 30L/fed with 50% of the recommended mineral N + 50% as organic N gave the highest nitrogenase and dehydrogenase activities and CO 2 evolution in rhizosphere as well as the macro nutrient content in seeds of peanut plants. The highest significant increases for all growth characters, yield and yield components of peanut were also recorded by the same treatment.