Nitrogen nutrition of tomato derived from the use of sewage sludge and almonds residue as fertilizers

Abstract

Sewage sludge and epicarp-mesocarp residue of almonds were used as fertilisers for tomato cultivated under greenhouse conditions in pots containing 15 kg of a calcareous soil. Three treatments were established: without organic fertilisation (W), with the addition of 0.5 kg of dry sewage sludge (SS) and almonds residue (AR). The nitrogen content of soil, stem+branches and leaves and nitrate reductase activity were determined. Growth and yield were also determined. Results showed that sewage sludge produced a general increment of N both in soil and plant tissue and improved growth and yield when compared with the other treatments. However, almonds residue did not produce significant differences between AR and W treatments.