Effect of municipal solid waste compost and sewage sludge use on wheat (Triticum durum): growth, heavy metal accumulation, and antioxidant activity.

BACKGROUND

Inappropriate utilisation of biosolids may adversely impact agrosystem productivity. Here, we address the response of wheat (Triticum durum) to different doses (0, 40, 100, 200 and 300 t ha(-1)) of either municipal solid waste (MSW) compost or sewage sludge in a greenhouse pot experiment. Plant growth, heavy metal uptake, and antioxidant activity were considered.

RESULTS

Biomass production of treated plants was significantly enhanced at 40 t ha(-1) and 100 t ha(-1) of MSW compost (+48% and +78% relative to the control, respectively). At the same doses of sewage sludge, the increase was only 18%. Higher doses of both biosolids restricted significantly the plant growth, in concomitance with the significant accumulation of heavy metals (Ni2+, Pb2+, Cu2+ and Zn2+), especially in leaves. Leaf activities of antioxidant enzymes (ascorbate peroxidase, glutathione reductase, catalase and superoxide dismutase) were unchanged at 40 t ha(-1) MSW compost or sewage sludge, but were significantly stimulated at higher doses (200-300 t ha(-1)), together with higher leaf concentration of reduced glutathione.

CONCLUSION

This preliminary study suggests that a MSW supply at moderate doses (100 t ha(-1)) could be highly beneficial for wheat productivity.