EARLY MORNING CANOPY TEMPERATURES FOR EVALUATING WATER STRESS IN A WHEAT CROP1

ABSTRACT: Several crop water stress indices were examined to determine their potential for use from a space-based system. These indices were compared using data collected over a wheat crop grown under arid environmental conditions. Indices that required concurrent ground-based measurements were less adaptable than the simple difference between canopy temperatures of a field with unknown stress conditions and a similar crop known to be unstressed. The results indicate that it would be feasible to develop space-based crop water stress techniques that would be useful for scheduling irrigations.