Relative drought tolerance of three grass species from the Northwestern slopes of New South Wales.

Abstract

On the north-western slopes of New South Wales, native pastures are subjected to frequent and often severe moisture stress during the summer growing season (Daniel and Watt 1967) so the relative drought tolerances of the component species may be important in determining pasture composition. Survival of three common native species from this area, Aristida ramosa R.Br., Danthonia linkii Kunth and Dichanthium sericeum (R.Br.) A. Camus, when subjected to water stress was compared in a glasshouse pot trial. The use of cycles rather than a single water stress in drought resistance studies, to simulate field conditions more closely, has been emphasised by Gates (1974). This experiment was designed to determine the relative tolerance of the above three species to repeated, increasing periods of water stress in a limited volume of soil. Pots of different sizes were used to determine the effect of differences in the rate of development of water stress on plant survival.