Crop Moisture Stress Analysis Using Computer-Controlled Environmental Chambers and Simulated Weather Sequences

ABSTRACT COMPUTER-CONTROLLED environmental plant growth chambers (PGC) were used to measure responses of water stressed and non-stressed corn and soybeans to simulated weather sequences. Simulated weather was patterned after actual hourly environmental conditions measured during a previous summer with a CR-21 weather station. Seasonal and diurnal crop water use in the PGC was controlled and monitored with an electronic lysimeter and a second computer system. Seasonal crop phenological responses were measured and show a remarkable pattern of stages of growth similar to field plants. LAST DAY measurements seed dry matter and seed number gave from 15.0 to 20.1 g per 100 seed and from 5 to 60 fruits per plant for soybeans. The PGC can be used to elicit the upper and lower limit growth responses to moisture-stress for certain crops.