Abstract:
Despite the agronomic, economic and nutritional values of maize (Zea mays), there is still dearth
of information on the water requirement of this crop in Imo State, South-eastern Nigeria. This
study was therefore carried out in Owerri, typical of the tropical rainforest zone of South-eastern
Nigeria to estimate the water requirement of early and late season maize planting based on ten
(10) years meteorological data (2004-2014) from Nigeria Meteorological Institute, Owerri
Directorate Office using the Penmans approach. Result shows that the seasonal crop
evapotranspiration was 309.30mm for early (March July) and 383.12mm for late (August
December) season planting. Generally, the total seasonal water supply from precipitation
exceeded the crop water need by 227% and 141% for late and early season cropping
respectively. However, moisture deficit of 67.91mm was observed during the maturity stage in
late season cropping, suggesting the need for supplementary irrigation at this growth stage to
meet the water requirement of the crop. This study has revealed that maize can be cultivated
entirely rainfed in Owerri without moisture stress if planted early season (March June), but if
it is late season cropping, supplementary irrigation of about 67.91mm must be provided in
December for optimum performance. In view of the excess moisture availability beyond optimal
crop requirement, it was further recommended that a complimentary crop should be intercropped
with watermelon in the farming system as a soil management practice to capture the excess
available moisture supplied through precipitation. |
