Agronomic performance of black oat (Avena strigosa Schreb.), cultivated in constructed wetlands

Abstract

This work aimed to evaluate the agronomic performance of black oat (Avena strigosa Schreb.), when cultived in constructed wetlands (CWs) in the treatment of domestic wastewater. The experiment was conducted in four CWs for secondary/tertiary treatment of domestic wastewater. The black oats were sown in the CWs at a density of 80 kg ha-1 of seeds. The organic loading rates (OLRs) applied in the CWs were 100, 200, 400 and 600 kg ha-1 d-1 of biochemical oxygen demand (BOD). The OLRs were obtained from results of analysis of BOD influent the CWs. The variables evaluated in influent and effluent of CWs were biochemical oxygen demand, chemical oxygen demand, total nitrogen, total phosphorus, potassium, sodium and electrical conductivity. In plant tissue the productivity of dry matter and the content of crude protein were evaluated. The productivity of dry matter for black oats were independent of OLRs applied. The highest yield of dry matter was obtained by applying 400 kg.ha-1 d-1 BOD. There was an average productivity of crude protein of 15.38 dag kg-1 in the black oat. The domestic wastewater can be a suitable nutritional solution for production of black oats in the CWs.