Abstract
When ginger rhizome seed pieces were germinated at constant soil tempera-tures of 20, 25, 30 and 35°C a significant quadratic relationship was observed between temperature and growth, the optimum temperature lying between 25 and 26°C. In a second experiment involving three constant temperatures (22·5, 27·5 and 32·5°C) and nine fluctuating temperature regimes corresponding with mean soil temperatures varying from 24·2 to 30·8°C, a marked effect of temperature was again found in the constant temperature treatments, best growth being obtained at 27·5°C. However, with fluctuating temperatures growth appeared to be somewhat less temperature dependent and the optimum lightly higher (29°C). The results are discussed in relation to soil temperature data from the ginger growing area of Queensland.
