
TY  - JOUR
A1  - Toft, NL 
A1  - McNaughton, SJ 
A1  - Georgiadis, NJ 
T1  - Effects of Water Stress and Simulated Grazing on Leaf Elongation and Water Relations of an East African Grass, <I>Eustachys paspaloides</I>
JF  - Functional Plant Biology
JO  - Functional Plant Biol.
Y1  - 1987
VL  - 14
IS  - 2
SP  - 211
EP  - 226
KW  - 
UR  - https://doi.org/10.1071/PP9870211 
N2  - Eustachys paspaloides was studied under conditions of water stress and simulated grazing (clipping) in the laboratory. Leaf and soil water potentials and leaf elongation rate (LER) were monitored during a 41-day drying period, and following rewatering. Water relations characteristics of tillers were derived from pressure-volume curves during the drought and recovery periods.    Water stress developed more slowly in clipped than in unclipped plants; predawn water potentials declined at mean rates of 0.13 and 0.38 MPa day-1 in clipped and unclipped plants, respectively. Consequently, leaf elongation of clipped plants continued approximately a week longer during the drying period than when plants were not clipped. Following rewatering, LER increased from zero to steady levels over 4 days.    Osmotic adjustment due to solute accumulation occurred in tillers of water-stressed plants. The difference in solute potential at full turgor between well-watered and stressed plants was 0.29 and 0.20 MPa for clipped and unclipped plants, respectively. The delay in permanent wilting afforded by lowered osmotic potential was about 1 day, indicating that osmotic adjustment is not a mechanism for reducing the effect of water stress on growth during long-term drought in Eustachys. However, osmotic adjustment may be an acclimation response to short-term drought during the growing season, and may aid in survival during the long dry season by limiting dehydration of the growing points. 
ER  -

