Effect of Different Durations of Water Withholding on Regrowth Potential and Non-Structural Carbohydrate Content in Rhodes Grass (Chloris gayana Kunth)

Abstract

The effect of water stress on the regrowth potential of Rhodes grass was studied in plants grown under controlled conditions at 27/22°C and 16-h photoperiods, and subjected to different periods of water withholding. After water was withheld, the levels of water-soluble carbohydrates (WSC) in the roots and basal parts of the leaves gradually increased from 2-4% to 8-9%, while the level of starch in the leaves remained stable below 1%. Regrowth and elongation of leaves that took place after cutting was increased markedly by withholding water for 6-10 days before cutting. A positive linear correlation was shown between initial leaf regrowth and the total amount of WSC present at cutting time. However, this initial advantage of the stressed plants gradually disappeared during the regrowth period, and no significant differences in leaf length and weight were found at later stages between the watered and stressed plants.