Composted and formulated poultry litters promote soil nutrient availability but not plant uptake or edamame quality

Abstract

Poultry litter can be a beneficial organic fertilizer if managed properly. Treating poultry litter can impact litter decomposition and nutrient release after application to soil. Knowledge about potential benefits to soil and crop quality from formulated pelletized or composted poultry litter amendments is limited. Few studies have focused on legumes and value-added crops such as edamame soybean. Here, we conducted greenhouse and field experiments in northwest Arkansas to investigate the effects of a composted and two formulated poultry litters applied at a 112 kg P ha−1 on nutrient availability and enzyme activities in a silt loam soil growing edamame. Litters were incorporated pre-plant, and soil parameters were monitored throughout the growing season. Plant nutrient concentrations and seed composition were measured at reproductive stages. Our results show that the composted litter and the two formulated litters have similar P content equivalent to about 5 % P2O5. Both litters increased Mehlich-3 and water soluble P in soil, with soluble P concentrations ranging from 33 to 316 % over the control. Dissolved organic C and inorganic N increased in the field following application of formulated poultry litter but not following application of composted poultry litter. Plant N and P uptake and seed nutritional value were not significantly increased by poultry litter addition. We conclude that composted poultry litter may be a better alternative for edamame production than formulated litters because it adds a more stable organic substrate to soil.