Working Document Series Open Access Effect of nitrogen and phosphorous rates and sources on grain and forage yield of maize in river Nile State A. Abd Elrahman · Ezeldeen Ahmed The study was conducted at two locations, namely, Hudeiba Research Station Farm (moderately fertile soil) and Matera (poor soil) in River Nile State for two seasons between 20082010. The objective of the study was to investigate the effect… RUF-34716 2010 CC BY 4.0 10 Sep 2015