Response to Temperature in a Stand of Pearl Millet

Abstract

Effects of temperature on the size of the leaf canopy, the stems and the panicles were investigated for stands of pearl millet in controlled-environment glasshouses. Expansion of each structure was examined in terms of a duration and a mean rate. The duration (t) for vegetative structures responded to temperature as a normal developmental period, in that l/t increased linearly with rise in temperature between a base (10 °C) and an optimum (30 to 35 °C). The rate for these structures also increased linearly with temperature between a similar base and optimum. Effects of temperature on rate compensated for those on duration, such that the leaf area index and height of the canopy were little affected by temperature. The panicles responded slightly differently in that length increased with rise in temperature by about 2% per degree. For all structures, rate, duration and size were little influenced by unsystematic differences between treatments in the rate of dry matter production.