Cotton Response to Poultry Litter Applied by Subsurface Banding Relative to Surface Broadcasting

摘要

Dry poultry litter is typically land applied by surface broadcasting, a practice that exposes certain litter nutrients to volatilization loss. Applying litter with a new, experimental implement that places the litter in narrow bands below the soil surface may reduce or eliminate such losses but has not been tested experimentally. The objective of this research was to quantify cotton (Gossypium hirsutum L.) lint yield and fiber quality improvements when fertilized with broiler litter applied in narrow subsurface bands at planting or after crop establishment compared with the traditional surface broadcast and standard inorganic fertilization. Applying litter at 6.7 Mg ha-1 increased lint yield from 984 kg ha-1 when applied by surface broadcast to an average of 1052 kg ha-1 when applied by subsurface band at planting or 1 mo later. Applying the same litter rate by subsurface banding 1 mo after planting had the added benefit of improving fiber properties, fiber length in particular. Chlorophyll index measurements showed that plants received greater N nutrition, suggesting that litter-derived N was conserved when the litter was applied by subsurface banding relative to surface broadcast. These results demonstrate that applying dry poultry litter in narrow subsurface bands with this implement conserves litter-derived N and may lead to a reduction in the litter application rate relative to the conventional surface broadcast method, with an added benefit of improved fiber quality when the litter is applied after crop establishment.