Partially treated domestic wastewater as a nutrient source for tomatoes (Lycopersicum solanum) grown in a hydroponic system: effect on nutrient absorption and yield

Shirly Tentile Magwaza; Lembe Samukelo Magwaza; Alfred Oduor Odindo; Asanda Mditshwa; Christopher Buckley

doi:10.1016/j.heliyon.2020.e05745

Partially treated domestic wastewater as a nutrient source for tomatoes (Lycopersicum solanum) grown in a hydroponic system: effect on nutrient absorption and yield

Heliyon. 2020 Dec 19;6(12):e05745. doi: 10.1016/j.heliyon.2020.e05745. eCollection 2020 Dec.

Authors

Shirly Tentile Magwaza^{1

2}, Lembe Samukelo Magwaza^{1

3}, Alfred Oduor Odindo³, Asanda Mditshwa¹, Christopher Buckley⁴

Affiliations

¹ Discipline of Horticultural Science, School of Agricultural, Earth and Environmental Science, University of KwaZulu-Natal, Pietermaritzburg, South Africa.
² Department of Agriculture, University of Zululand, Private Bag X1001, KwaDlangezwa, 3886, South Africa.
³ Discipline of Crop Science, School of Agricultural, Earth and Environmental Science, University of KwaZulu-Natal, Pietermaritzburg, South Africa.
⁴ Pollution Research Group, Faculty of Engineering, University of KwaZulu-Natal, Howard College, Durban, South Africa.

Abstract

Using effluent from the anaerobic baffled reactor (ABR) of the decentralised wastewater treatment system (DEWATS) as a sole nutrient source is not sufficient for tomato plants grown in hydroponic system. The study investigated the effects of commercial hydroponic fertilizer mix (CHFM) combined with ABR effluent on tomato growth and yield. A media-based hydroponic technique consisting of three treatments, namely, ABR effluent, CHFM, and ABR effluent combined with CHFM (ABR + CHFM (50:50 v/v) was used. The results showed that plant growth parameters, biomass, fruit yield and shoot nutrient content were significantly higher in tomato plants fed with CHFM and ABR + CHFM than those grown in ABR effluent. Addition of 50 % dose of CHFM in ABR wastewater (ABR + CHFM) increased shoot N, K, Ca and Zn. These results indicated that adding 50% CHFM can alleviate nutrient deficiencies when partially treated wastewater from anaerobic digester is used as a nutrient source for hydroponic tomato cultivation.

Keywords: Agricultural water management; Crop biomass; Crop production; Crop yields; Greenhouse technology; Horticulture; Human excreta-derived materials; Hydroponic system; Mineral nutrients; Nutrient recovery; Waste disposal.