ECOPHYSIOLOGY OF BANANAS: THE GENERATION AND FUNCTIONING OF THE LEAF CANOPY
Productivity in bananas is governed by 'source' and 'sink' components of the plant system. Source components include intercepted radiation, and radiation use efficiency. Sink components include estimates of sink size, such as harvest index and the number of bunches present, and sink activity expressed as a temperature coefficient.
At the individual leaf level recent work has demonstrated the non-saturating light response curve for net photosynthesis of individual leaves. This means that banana leaf canopies will be sensitive to shading. Banana leaves are very hydrated tissues that resist drying by rapidly closing their stomata. Leaf tearing reduces productivity independently of the effects of wind speed and the stomata on shredded leaves partially close so that the temperature of torn and untorn leaves remains quite similar. Experiments on root restriction and partial drying of the root system demonstrate the direct link between root function and stomatal conductance. These interactions have significance for planting dates, densities, root health and water management regimes.