1a. Objectives (from AD-416)
The objective of this study is field evaluation of nitrogen availability from fresh and pelletized litter for corn production. Most of the studies on evaluating manure on N availability have been conducted in a completely controlled condition using incubation studies in the laboratory with no crop or greenhouse studies using crops for biomass production. Prediction of manure nitrogen availability in the field to crops is key to ensuring adequate nutrient supply to maximize yields while avoiding over application and minimizing adverse environmental impact. Currently, broiler litter is being pelletized to increase the economic feasibility of transporting broiler litter from the production areas to the places it is needed such as row crops. Fresh broiler litter has been used for row crops as an alternative source of fertilizer N but pelletized litter has not been used on row crops yet, probably because of the price. Field studies comparing these two types of broiler litter are necessary to provide more information for the farmers who might be interested in using pelletized litter on their row crops in the near future.
1b. Approach (from AD-416)
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.
3. Progress Report
Proper broiler litter management as an alternative source of N is essential for the production of high-yielding corn. This project was conducted in a no-till corn to determine the effects of broiler litter source (fresh vs pellitized) and placement (band vs broadcast) on grain corn and N utilization. Broiler litter was applied in both fall and spring. Leaf N concentration and chlorophyll content using SPAD meter are determined at tasseling stage. Grain yield, N concentration, and soil residual NO3-N are evaluated. The ADODR monitored this project by discussions with the principal scientist involved in this research. The principal scientist has frequent contact with the cooperator.