Growth of Tomato Seedlings in Commercial Substrate Amended With Dewatered Aquaculture Effluent

Abstract

Dewatered aquaculture effluent (AE) could replace portions of commercial potting mix for tomato (Solanum lycopersicum L.) seedling production. In two separate experiments, tomato, cv. Bolseno, seedling growth responses were evaluated when a commercial potting mix was amended with 0%–75% of AE (v/v) and fertigated with a water-soluble, complete inorganic fertilizer. In Experiment 1, differences existed for seedling plant height, leaf area, leaf dry matter, stem dry matter, and total dry matter 2 weeks after transplanting. Plant growth parameters decreased when AE was ≥25% container volume due to suboptimal physical and chemical properties of the substrate. In Experiment 2, commercial potting mix replaced with 5% AE improved plant height, leaf area, leaf dry matter, stem dry matter, and total dry matter by 26%, 124%, 87%, 75%, and 83%, respectively, compared to the control. Plants grown in substrates with 10% and 15% AE had greater plant height and leaf area compared to the control, whereas other growth parameters were similar to the control. Dewatered aquaculture effluent could amend a commercial potting mix at quantities ≤15% (by volume) for production of greenhouse-grown tomato seedlings.