Residual effect of composted olive oil mill sludge on plant growth

Abstract

Residual effect of a composted olive oil mill sludge on growth and mineral composition of tall fescue (Festuca arundinacea) was studied. Results were compared with those obtained for a mineral fertilizer treatment and a control. Compost and inorganic fertilizer had been previously applied to two different soils at two rates for five years. The compost did not display the phytotoxicity of olive oil mill wastewater, and produced, at high doses, the highest yield and concentrations of P and K in tissue, while decreasing Na, Mn, and Zn assimilability.