Start Date: Apr 01, 2009
End Date: Mar 31, 2012
This study will be conducted in a no-till corn at a private farm near Caledonia, MS. Treatments will consist of three N sources and four rates. The N sources include inorganic fertilizer N (ammonium nitrate), pelletized poultry litter (PPL), and fresh poultry litter (FPL). Fresh and pelletized litter will be applied at the total N rate of 0, 124, 248, and 496 lb/acre. Inorganic fertilizers will be applied at the rate of 0, 80, 160, and 240 lb N acre. Corn plant samples will be collected at the sixth-leaf (V6), 12th-leaf (V12), tassel (VT), and physiological maturity (R6) growth stages for dry matter production and N uptake estimations. Grain yield and grain N uptake will be determined. For each rate and source, grain N recovery will be calculated. Post-harvest residual inorganic N will be determined. Using all above mentioned factors and fertilizer N equivalence method based on grain yield and grain N uptake, the available N from total N applied by fresh and pelletized litter will be estimated in the field condition. Also the corn harvest index will be determined as a ratio of corn grain yield to above ground biomass without corn grain at physiological maturity, economic optimum N rate, and maximum N rate in relation to corn grain yield will be determined for both fresh and pelletized broiler litter. The effects of timing (fall vs spring), placement (band vs broadcast) on available N will also be evaluated for both fresh and pelletized litter.