Computing Maize Crop Coefficients in the Port Harcourt area,Nigeria,using a Class a Pan Evaporimeter

Abstract

Farmers in hot tropical climates know the importance of irrigation, but for irrigation to be used effectively the water requirement of the crop must be known. This is computed as the product of the potential evapotranspiration (PET) and the crop coefficient (K_c). While the PET can easily be obtained through various methods, including pan evaporimeters, the K_c in the Port Harcourt area for maize and other crops was not known. The main objective of this research, therefore, was to obtain maize crop coefficients at different stages of growth using non-weighing water table lysimeters and a class A pan. The estimated mean maize evapotranspiration (ET) values for the establishment, vegetative, pollination, and grain-filling stages were 29,98,84 and 98 mm, respectively. Values ranging from 0.18 to 1.08 were calculated for the mean crop coefficients for 10-day periods.

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