Influence of Harvest Factors on Cotton Yield and Quality

Research studies were conducted during the 1980s to evaluate the relationship between harvest systems, harvest aid chemicals, and harvest environments to cotton yield and quality. Cotton yield and quality were reduced in three out of five years with once over and delayed harvesting compared to twice over harvesting. The most significant factor influencing yield and grade in these studies was rainfall occurring after the cotton was open. Rainfall totaling 50 mm or more significantly reduced yield and quality. Defoliation reduced lint yield by an average of 44 kg/ha but increased grade index. Application of Prep (ethephon) to accelerate boll opening significantly reduced yield and grade if applied at the 40% or 60% open stage, but had no detrimental effect on yield or grade if applied at the 80% open stage.