A Novel Screening Method of Water Stress In Multiple Cotton Varieties

One of the challenges with genetic selection of cotton for yield and fiber quality is the assessment of phenological changes in the plant that impart improved yield and quality.  Because specific growth functions are not correlated the end result, selection is based on only final yield and quality.  Unfortunately, this causes a “black box” approach to variety selection, in which the factors are final yield and quality, as opposed to specific growth habits that improve yield.  Add to this the difficulty in screening for drought tolerance characteristics in a field setting, and it is understandable that there are limitations to genetic improvement.  We propose a method for screening large numbers of plots using multiple remote sensing technologies to identify factors that can be identified as contributors to final yield and quality in irrigated and nonirrigated situations.  During the summer of 2007, a research cart carrying a GreenSeeker spectrometer, an Apogee Instruments infrared thermometer, a Trossen Robotics distance sensor, and Apogee Instruments PAR sensors was used to determine physiological changes in 15 varieties of cotton.  Measurements included a vegetation index, canopy temperature, plant height, and crop radiation capture.  Significant differences were identified between varieties, as well as between irrigated and nonirrigated treatments, suggesting that this method might be expanded upon to supply a phenological and physiological screening method for yield and quality measurements.