|Wrather, J - UNIVERSITY OF MISSOURI|
|Phipps, B - UNIVERSITY OF MISSOURI|
|Stevens, W - UNIVERSITY OF MISSOURI|
|Phillips, A - UNIVERSITY OF MISSOURI|
Submitted to: Journal of Cotton Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 14, 2008
Publication Date: April 11, 2008
Citation: Wrather, J., Phipps, B., Stevens, W., Phillips, A., Vories, E.D. 2008. Cotton Planting Date and Plant Population Effects on Yield and Quality in the Mississippi Delta. Journal of Cotton Science. 12(1):1-7. Interpretive Summary: Cotton producers in the Mississippi Delta plant in early spring, but weather conditions often develop that reduce plant populations and the producers must occasionally decide whether to replant. A series of studies were conducted in southeast Missouri with the objective of determining the effects of planting date and plant population on cotton production. The results showed that crop maturity was delayed for later planting dates and lower plant populations and suggested that producers should not replant low cotton populations after mid-May in most cases. The findings from this research will benefit all cotton producers, but especially those in the northern cotton-producing areas where growing seasons are shorter than in other regions.
Technical Abstract: Cotton producers in the Mississippi Delta plant in early spring, but wet, cold weather often develops then and may reduce plant population directly or indirectly. Producers must occasionally decide if replanting is necessary. The objective of these studies was to determine planting date and plant population effects on cotton yield, lint quality, and crop maturity in the Mississippi Delta. Three separate field experiments were conducted during 2001-2005. For the planting date × plant population experiment, seed cotton yields for the late-Apr. plantings were significantly greater than for other planting dates, and seed cotton yields for 33,976, 67,952, and 135,904 plants ha minus 1 were significantly greater than for 16,988 plants ha minus 1. Yield for late-Apr. planted cotton at 16,988 plants ha minus 1 was significantly greater than or equal to yields for mid-May planted cotton at all plant populations. For the planting date experiment, lint yields and percent lint were significantly greater for early than late plantings three of five years, and micronaire was significantly greater for early than late plantings each year. For the plant population experiment, lint yields were significantly greater for 33,976-135,904 than 23,782 plants ha-1 two of four years. There were no plant population effects on lint quality. In all experiments, crop maturity was delayed for late planting dates and low plant populations. Producers in the Mississippi Delta should not replant cotton after mid-May if the plant population from a late-April planting is 16,988 or more plants ha minus 1.