Submitted to: American Society of Plant Physiologists Meeting
Publication Type: Proceedings
Publication Acceptance Date: 7/24/1999
Publication Date: N/A
Technical Abstract: Cotton grown under rainfed conditions undergoes cycles of water stress and recovery. The ability of the plant to reestablish normal growth following rain events will affect productivity. Reduced leaf expansion is a characteristic of cotton under water stress. In this study cotton was grown under irrigated and rainfed conditions. The rate of expansion (over a 24-hour period) was determined twice weekly for the uppermost unfolded apical leaf (<0.05 cm^2). The water potential of the plant was determined on the fourth leaf at the end of the 24-hour period. Expansion rates in the irrigated treatment exceeded those in the rainfed for the majority of measurements. Expansion rates increased in response to irrigations while rainfall of at least 2 cm was required to increase expansion in the rainfed treatments. Recovery of expansion in response to water was more rapid in irrigated as opposed to rainfed treatments. Comparisons of water amount and drecovery time/extent with the rainfall patterns common to the region may provide information on the desirability of various recovery behaviors under rainfed conditions.