Integrated Management of Nitrogen Sources for Maize.

Nitrogen use efficiency always demands for better utilization of the available resources to overcome application losses and reduce the cost of production. Integrated application of organic and inorganic sources of nitrogen could be a possible solution. So, a field experiment was conducted to evaluate yield potential of hybrid maize (32-W-86) with different nitrogen sources (urea, farmyard manure and poultry manure in different combinations) at the Agronomic Research Area, University of Agriculture Faisalabad, Pakistan. The experiment was conducted for two consecutive years (2006 & 2007) in a Randomized Complete Block Design (RCBD) with three replications. A total requirement of 250 kg N ha^-1 for maize hybrid was obtained from the three sources either alone or in different combinations. The treatments included were control, 100% N from FYM, 25% N from Urea + 75% N from FYM, 50% N from Urea + 50% N from FYM, 75% N from Urea + 25% N from FYM, 100% N from Urea, 100% N from PM, 25% N from Urea + 75% N from PM, 50% N from Urea + 50% N from PM and 75% N from Urea + 25% N from PM. Results revealed that during both years (2006 and 2007) the maximum grain yield (7.20 t ha^-1 & 7.66 t ha^-1), plant height (252.43 cm & 263.3 cm),  stem diameter (1.97 cm & 2.01 cm), cob diameter (4.26 cm & 4.30 cm), cob length (24.97 cm and 25.03 cm), number of grains per cob (400.6 & 411), 1000-grain weight (268.32 g & 274.7 g), biological yield (20.19 t ha^-1 & 20.48 t ha^-1) and seed protein content (8.80 % & 8.89 %) were obtained by applying 50 % N from urea and 50 % N from PM. This combination was also proved the most economical one for the farming community as maximum BCR (3.53 & 3.77) was observed in both the years. It is also concluded that synergistic and complementary effects can be seen on yield and yield components of maize with the integration of organic and inorganic fertilizers application.

Keywords: Maize; FYM; Poultry manure; biological yield; grain yield