Poultry Litter and Cover Crop Integration into No‐till Cotton on Upland Soil

Abstract

Core Ideas Applying poultry litter to the top of cover crop residue increased lint yield in drier years.This practice enhanced cotton lint yield, soil C, and soil health.This practice reduced NO3–N and water‐soluble P by 49 and 22% in 5‐cm soil depth, a zone of plant–soil–water interactions. The influence of poultry litter (PL) and cover crops have under no‐till cropping systems in Mississippi upland soils on cotton (Gossypium hirsutum L.) yield and subsequent soil health are largely unknown. A 4‐yr field study was conducted to determine the effect of winter wheat (Triticum aestivum L.) cover crop and PL on cotton lint yield in narrow (0.75 m) and conventional (1.01 m) row spacings. The experimental design was split‐split plot with three replications. The cover crop treatment was assigned to the main plots. Within the cover crop treatment, a narrow row spacing compared to conventional row spacing as subplots. Fertilization treatments included unfertilized control, inorganic N fertilizer (112 kg N ha−1) and PL (6.7 Mg ha−1). Lint yield was significantly greater with PL than inorganic fertilizer each year. Lint yield in a dry season was significantly greater with cover crop treatment. However, following the cessation of PL in 2017, lint yield increased by 12% in the absence of cover crop residue. As compared to unfertilized control, applying PL in the presence of cover crop residue enhanced soil C by 22% and water aggregate stability by 7.4% and reduced soil penetration resistance and bulk density by 9 and 3.5%, respectively. Applying PL for 3 years increased soil levels of both gram‐negative bacteria, 16S rRNA, and ureC, while planting cover crop doubled heterotrophic plate count bacteria. Integration of PL and cover crop residue in a no‐till cotton increased lint yield and improved soil quality indicators.