Effects of Various Residue Management Systems on Cotton Establishment and Yield in High-Residue

Abstract

A field experiment was conducted in 2007 and 2008 in central Alabama to evaluate the effects of mechanical termination cover crop, strip tillage width, and row cleaners attached either to tillage implement or planting units, on cotton population and yield. Treatments included roller (present or absent), in-row subsoiler (wide and narrow strips), and row-cleaners attached either to subsoiler, planter or both. In both years rye was terminated with glyphosate (both rolled and non-rolled rye) in mid-April, and tillage treatments were applied; cotton was planted three weeks after tillage. In 2007, generally higher cotton stands were associated with rolled rye residue (137,134 plants/ha) v/s non-rolled rye (115,641 plants/ha). On average, significantly higher cotton seed yield was found for rolled rye (4,540 kg/ha compared to non-rolled rye (4,332 kg/ha). Examining specific treatments, the highest cotton seed yield (4,933 kg/ha) was associated with rolled rye under narrow strip tillage with row cleaners attached to both subsoiler and planter. The lowest cotton yield (3,913 kg/ha) was associated with non-rolled residue, under narrow strip tillage with row cleaners present on both subsoiler and planter. In 2008, no difference was found in cotton stand for rolled (108,375 plants/ha) and non-rolled rye (107,719 plants/ha). Cotton seed yield in 2008 was higher than in 2007 due to a severe drought in Alabama during 2007. In 2008, slightly higher cotton yield was reported for non-rolled rye (5,658 kg/ha) v/s rolled rye (5,419 kg/ha). The non-rolled rye, narrow strip subsoiling and row cleaners on subsoiler produced the highest cotton yield (5,812 kg/ha) compared with the lowest (5,171 kg/ha) by rolled rye, narrow strip and row cleaners on the planter. In 2007 and 2008, the width of the tillage strip did not have a significant effect on cotton stand or cotton seed yield.