Evaluation of Different Techniques for Quantifying the Physiological Response of Cotton under High Temperatures

Extreme variability in cotton (Gossypium hirsutum L.) yields from year to year, as well as a lack of any noticeable increases in yield over the past decade, has caused major concern for producers. Although yield is mainly controlled by genetics, environment, and cultural inputs, it is now believed that temperature is one of the major factors affecting the development of cotton yield. Our earlier work has indicated a strong negative correlation between high temperatures and low cotton yields in Arkansas. However, there is limited information on the effects of high temperature on the physiology and growth of cotton. In this study, it was hypothesized that numerous physiological and biochemical parameters will be affected by elevated temperatures, but only a few of these will be both sensitive to high temperatures and easy to measure in large breeding trials.