Evaluating the Effectiveness of Some Productivity Models on Floodplain Soils of Wukari Area, Northern Guinea Savanna, Nigeria

A study on quantifying the productivity of Wukari flood plain soils using Neill’s Productivity Index (PI), Modified Neill’s Productivity Index (PIm) and Riquier Productivity Index (RI) was carried out. The applicability and validity of the productivity index models were determined using rice as a test crop. Result showed significant relationships with coefficients of determination (R2) of 0.7158, 0.7204 and 0.8778 found between grain yield of rice (Y) and PI, PIm and RI values respectively. The highest and the lowest grain yield of rice to a reasonable extent correspond to the higher and the lower productivity index values, respectively. Higher productivity indices explained higher mean grain yield of rice. The productivity indices values decreased with the decrease in grain yield. The grain yield of grain followed productivity index predictions and are hereby recommended as tools of soil productivity assessment in the study area.