A SWACROP-based potato root water-uptake function as determined under tropical conditions

The SWACROP root-water uptake function for potatoes was determined in the 1994-95 crop season on a Ferralsol in Havana province, west Cuba. The maximum pressure-heads under which water is optimally extracted by potato roots were very similar to the original Feddes function. Nevertheless, the anaerobiosis point and the wilting point pressure-head in both functions were not in agreement. However, the simulated values of soil water contents in the 0-40 cm soil depth by performing SWACROP runs in the 1995-96 potato crop season using both functions were very similar. The original Feddes function seems to be good enough for predicting soil water contents in the tropics and no specific other functions need to be developed for any particular soil or climate condition.