Effect of Organic Sources of Nitrogen on Soil Fertility of Cowpea [Vigna unguiculata (L.) Walp]

Background: Cowpea [Vigna unguiculata (L.) Walp] is most widely grown pulse-cum-vegetable crop. It plays an important role in maintaining soil fertility. Besides, nitrogen which fixed the from atmosphere by crop specific Rhizobium found root nodules of this crop, phosphorus another element inter-alia enhances fixation capability In addition to biologically nitrogen, also requires through fertilization meet its initial requirement (Mishra and Baboo, 1999). Methods: A field experiment was on conducted during kharif season year 2015 at Agronomy Instructional Farm, C.P. College Agriculture, Sardarkrushinagar Dantiwada Agricultural University, Gujarat. The laid out randomized block design with four replications 10 treatments comprising integration different organic sources. Result: Our investigation significant improvement N content seed uptake cowpea were noted application 50% FYM + vermicompost PSB (T8), whereas, higher stover P recorded under treatment T9 (50% castor cake PSB) T10: RDF (20+40+00 kg ha-1 NPK Fertilizer), respectively. Treatment T10 contributed raise potassium seed, K available after harvest