Application of rainfall-potential evapotranspiration model for determining optimum planting date of maize (Zea mays) in a tropical wet and dry climate

Abstract

Rainfall-poteritial evapotraspiration model was used to determine the optimum planting date of maize (Zea mays
L.) grown during the rainy seasons of 1995 and 1996. The date whim the accumulated difference between rainfall and
hulf the potential evapotranspiration equals zero or slightly above it (April 15 and April 13 in 1995 and 1996 respectively)
marked the optimum planting dates. Planting on these dates gave the highest grain yield during the respective year.
Considerable reduction in yield however occurred for planting done when the accumulated difference between rainfall
and 0.5 Potential evapotranspiration was in excess of 20 mm; and this represented a delay in planting by about 10 days after the optimum date. The implication of the study for appropriate schedule of farm operations vis-a-vis agronomic
practices for maize cultivation have been noted.