DOES FERTILIZING SOYBEAN WITH POULTRY LITTER ENRICH THE GRAIN WITH MINERAL NUTRIENTS?
Prasad, R.1; Singh Rajveer2; Sandlin Tyler3; McGriff Eddie41Assistant Professor and Extension Specialist, Alabama Cooperative Extension System, Auburn University, AL, 36849
2Graduate Research Assistant, Auburn University, Auburn, AL, 36849
3Assistant Res Professor/Assistant Extension Professor, Alabama Cooperative Extension System, Belle Mina, AL, 35615
4Regional Extension Agent, Alabama Cooperative Extension System, Cullman, AL, 35055
Abstract:
Alabama ranks second in broiler production nationwide generating 1.5 million tons of poultry litter (PL) each year. Many row crop farmers in Alabama are using PL as a slow-release nutrient source in their row crop production system including soybean (Glycine max L.). However, little is known about the effect of PL on soybean grain yield and nutrient composition. The objective of this study was to evaluate the effect of PL on soybean grain yield and seed nutrient composition in response to three application rates (1, 2.5, and 5 tons/acre). A two-year replicated field plot study was conducted during the 2018 and 2019 growing season on a Compass loamy sand in central Alabama. Treatments included pre-plant PL application (2 weeks before planting) at three rates (1, 2.5, and 5 tons/acre) and a control plot (no litter). Soybean cultivar (AG74X8; Maturity group-7) was planted on June 14th and harvested on 20th November. Plot yields were determined by combine harvesting the middle two rows. Grain nutrient content of total nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), calcium (Ca), sulfur (S), boron (B), zinc (Zn), manganese (Mn), iron (Fe) and copper (Cu) were determined according to the routine procedure. Data analyses were performed using PROC GLIMMIX of SAS 9.4. Poultry litter significantly affected soybean grain yield in 2019 (P<0.05). The PL-treated plots had a 42% greater grain yield than the control plots. The PL application rate of 5 tons/acre resulted in the highest grain K and Cu concentrations and differed significantly (P<0.05) from the 2.5 ton/acre application rate and the control treatment.