Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: November 1, 1999
Publication Date: N/A
Technical Abstract: The generally dry, warm, and windy environment of the Texas High Plains can subject plants to water stress, especially as available soil water decreases. Plants react to water stress by closing stomata. Our objective was to quantify the stomatal response of alfalfa to atmospheric- and water deficit-induced stress. For each of the two cuttings, alfalfa was irrigated until leaf area index was about 2.5 m**2 m**-2. Then, irrigatio was continued on one half of the 9.5 ha field and discontinued on the other half. A closed-chamber portable photosynthesis system was used to measure stomatal conductance of irrigated and non-irrigated, fully-sunlit leaves during daylight hours for two or three days per week until harvested. Soil water content was continuously measured by time domain reflectometry.