The effects of superphosphate application and mucuna (Mucuna pruriens) management options on chemical characteristics of a sandy loam soil in Zimbabwe

Low soil fertility due to monoculture crop production systems is recognized as one of the major biophysical causes for declining per capita food production in sub-Saharan Africa. The major objectiveof this research was to investigate the effect of two superphosphate levels and four mucuna management options on soil chemical properties on a depleted kaolinitic sandy soil in Zimbabwe. The two phosphorous treatments were P0 = 0 kg P ha-1 and P40 = 40 kg P ha-1 and the four mucuna treatments were MF = mucuna incorporated at flowering, MAR = mucuna above ground biomass removed at maturity and only roots incorporated, MPR = above ground biomass except pods incorporated at maturity and F = Fallow (control). The following soil nutrients were investigated; Nitrogen, Phosphorus, Potassium, Calcium, Magnesium and Zinc. The MF and P40 treatment combination resulted in the highest N, P, K, Ca and Mg levels. However the P40 and mucuna treatment combinations had significantly lower Zn levels than the P0 and mucuna treatment combinations.    Key words: Exchangeable bases, major nutrients, mucuna.