Assessing the Reliability of Treated Grey Water Irrigation on Soil and Tomatoes (Solanum lycopersicum L.)

Under a water scarcity situation, it is expected to manage water more efficiently. This study aims to evaluate the effect of treated grey water (from laundry and tableware), pre-treated through a wetland mini-reactor with a horizontal underground flow, on soil and tomatoes. The experiment included two tomato cultivars (Dart and Firenze), planted in completely randomized bloc design, and irrigated with treated grey water (TGW) vs. ground water (C) as control. Soil, tomato leaves and fruits were assessed for microbial contamination. Tomato yield, physico-chemical characteristics and antioxidant contents were studied. Results showed that TGW met the standards for irrigation water for most water quality variables. Irrigation with TGW increased the concentrations of phosphorus (P), iron (Fe) and copper (Cu) in the soil. Although, the soil ionic composition was still in the suitable range for agriculture. Opportunely, there was no contamination by fecal coliforms, streptococcus and E. coli in soil and tomatoes. Dart cultivar seems to be more responsive to TGW and had higher fruit number and weight. This response was accompanied by an effective antioxidant response, higher water and juice content. The findings of this study emphasize that TGW may provide a way to preserve water resources and to avoid soil contamination.