The regression and correlation analyses of okra yields at different rates of
RHA and P treatment indicated no significant linear correlation at p , 0.05
in both experiments. The initial soil pH, explorable volume of the soil, and the
source of P contributed immensely to the observed P responses. The field
soil analysis 12 WAP in Table 9 indicated that soils treated with RHA
(5–20 t ha21) and monopotassium phosphate (20–40 kg P ha21) had higher
available P with a mean of 107.49 mg kg21 (Table 9, less control), which is
43.34% higher than its initial level of 74.99 mg kg21 (Table 2). Similar increments
were observed for K and ECEC, which were respectively 27.17% and
20.20% higher in the RHA plots than their initial levels.