Effect of Plant Growth Regulators On Lint Yield, Fiber Quality, and Boll Distribution of Cotton Varieties in Georgia

Plant growth regulator (PGR) applications are often necessary in cotton to reduce vegetative growth and maintain a manageable crop.  However, PGR sensitivity varies widely among varieties and environments.  Some varieties need to be monitored closely and heavily managed while some are sensitive such that overuse may negatively impact yield.  Research in 2012 investigated the response of various varieties managed with either no PGR applications or a heavy PGR regime which included multiple applications made pre-bloom and during bloom.  Immediately prior to harvest, planting mapping was conducted which documented total number of bolls produced, boll distribution, plant height, and total number of main-stem nodes.  Boll production data were grouped into node zones, by fruiting position and within main-stem nodes 5 to 8, 9 to 12, 13 to 16, 17 to 20, and 21 and up.  This data, along with lint yield and fiber quality were used to more adequately understand differences in PGR requirements of cotton varieties in Georgia.