Research and Development Institute for Agricultural Systems under Adverse Conditions, Kasetsart University, Bangkok 10900, Thailand.

Abstract

The effects of the duration of water stress on forage quality of purple guinea (Panicum maximum Jacq.) were determined by using the accumulation of praline content during water stress as and indicator for drought tolerance. The plants were subjected to water stress for 10, 15 and 20 days before praline, protein, and acid-detergent fiber analyses. It was found that protein content of guinea grass decreased under the short period of water stress condition, but increased then the stress was prolonged. Protein content was similar to the control when plants were subjected to water for 20 days. Acid-detergent fiber increased under water stress condition. However, different durations of water stress had no effect on the quantity of acid-detergent fiber. Proline content increased as the duration of water stress increased. The results suggested that purple guinea tends to acclimate to drought as considering from the change in its proline and protein contents.