Development and Growth of Pearl Millet (Pennisetum typhoides) in Response to Water Supply and Demand

Abstract
Stands of pearl millet were grown in three controlled environment glasshouses in which were imposed different combinations of atmospheric saturation deficit (1.5 to 2.3 kPa) and soil water content (fully irrigated and not irrigated). Consistent differences in saturation deficit (SD) were maintained throughout the experiment (100 days) but a high water table restricted differences in water supply to the first 40 days. Responses to SD and soil water were observed in some variables but not in others. Developmental processes such as the rate of leaf appearance were unaffected, whereas the efficiency for conversion of intercepted solar energy decreased by 24% and the rate at which the canopy expanded by 50%, in the driest compared to the wettest conditions.