ARS | Publication request: Effects of broiler litter rate, timing and cover crop on cotton yield and residual soil N

Submitted to: American Society of Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: April 30, 2009
Publication Date: N/A

Technical Abstract: Timing of broiler litter applications has critical effect on the availability of litter-derived nutrients and should affect cotton (Gossypium spp.) growth and yield. This experiment was conducted on a Leeper silty clay loam (fine, montmorillionitic, nonacid, thermic Vertic Haplaquepts) soil at Mississippi Plant Science Research Center to quantify the effects of cropping system [(winter rye (Secale cereale L.) cover crop vs. winter fallow)] and time of broiler litter application (fall vs. spring) on cotton yield and soil residual NO3 from fall 2006 to fall 2008. Broiler litter was applied at the rate of 0, 4.5 and 9 Mg ha-1 and incorporated immediately. Fall applied broiler litter coupled with winter rye cover crop increased cotton lint yield by 8 and 17% in 2007 and 2008, respectively, compared to winter fallow. However, spring applied broiler litter to cover crop residue and incorporated into the soil before planting cotton resulted in lower lint yield than the plots with no cover, indicating possible reduction of available N by N immobilization used for decomposition of plant residue. With no cover crop, spring application of broiler litter resulted in greater cotton lint yield than fall application due to potential leaching losses of NO3-N for fall applied litter. Mean NO3-N concentration in the leachat samples collected at 60 cm depth during late fall, winter, and early spring from fall applied broiler litter was significantly reduced with the winter rye cover crop by 86% compared to winter fallow. This indicates overseeding a catch crop to fall applied broiler litter appears to reduce leaching losses of NO3-N and increase recovery of N for subsequent crops in the spring.