Effects of Water Stress on Proline Content and Forage Quality

Abstract

Drought is one of the major environmental factors affecting forage quality. The objective of this study was to determine the effects of water stress on praline content and quality of two forage crops; purple guinea (Panicum maximum Jacq.) and verano stylo (Stylosanthes hanata cv. Verano). The plants were subjected to three drying cycles. At wilting of each cycle, leaf samples were collected for the analyses of praline, protein and acid-detergent fiber contents. It was found that under water stress condition, protein content decreased in purple guinea, but increased in verano stylo. Water stress had no effect on acid-detergent fiber content in both species. In purple guinea, proline content increased about 6 folds at silting, compared to control, and decreased to the control level after recovery. The second drying cycle had very little effect and third drying cycle had on effect on praline content. There was no correlation between praline content and forage quality of purple guinea in this study. The longer water stress treatment might be needed in order to get the significant effect on forage quality.