Pelleted biosolids and cover crop effects on major Southern row crops

Abstract

Pelleted biosolids (PBS) can be used as a low-cost nutrient source alternative to conventional fertilizers for row crop production. A field study was conducted on a Marietta loam at the Plant Science Center at Mississippi State to determine the response of row crops to PBS relative to poultry litter (PL) and inorganic fertilizer N in the presence/absence of cover crop residues. Fertilization treatments included PBS and PL at agronomic rate, PBS as one-time single application at the high rate, inorganic fertilizer N, and unfertilized control. At agronomic rate, PBS and PL relative to inorganic fertilizer had similar effects on corn (Zea mays L.) grain and cotton (Gossypium hirsutum L.) yields N and P utilizations. However, in 2019, corn grain yield and grain N uptake with PBS were less by 31% and 55% as compared to inorganic fertilizer, respectively. Pelleted biosolids and PL had similar residual effects on soybean (Glycine max L.) grain yield and grain N and P uptakes. Averaged across fertilization treatments, the presence of winter wheat (Triticum aestivum L.) cover crop residue significantly increased seed cotton yield by 7% as compared to winter fallow. One-time single application of PBS at the high rate resulted in significant NO3–N concentration below 30 cm and substantial P accumulations at the top 15 cm soil depth. At the agronomic rate, PBS can be considered as an alternative effective fertilizer for row crop productions.