Summaries of Arkansas Cotton Research in Progress in 2001

Cotton yields in Arkansas increased steadily during the eighties, but in recent years there has been a leveling off. Of more significance, however, is that extreme year-to-year variability in yields has occurred in the last decade, which is a major point of concern with cotton producers. It has been suggested that this may be related to extreme weather conditions during the boll development period in July and August. Average maximum temperatures in the 2001 season were a few degrees above normal. Recent research in Arkansas has indicated that elevated night temperatures during boll development may be a major contributory factor to low and variable yields. There is also evidence that yield variability in stressful seasons may be related to genotypic changes in the components of yield, seed number, and fiber per seed, over the last 30 years. Yield stability for Arkansas cotton producers has become a major focus for new in-state collaborative research projects