Bioponics in Tomato Cultivation Toward Sustainable Farming: Evaluation of a Circular Tri-Trophic System Incorporating Aquaponics and Insects

Bioponics is a promising agricultural system designed to integrate circular economy principles by recovering nutrients from organic waste. In this context we implemented a tri-trophic circular system, where insect larvae fed on crop residues and fruits were processed into insect meal for fish feed. The water used in fish rearing then irrigated tomato crops in an aquaponic setup, closing the nutritional loop. Tomato was cultivated in this system with the aim of thoroughly evaluating its applicability via assessing the dynamics of growth, yield, and functional responses of the crop across three treatments: coupled aquaponics (CAP), decoupled aquaponics (DCAP), and hydroponics (HP, as control). DCAP matched HP in all parameters assessed and even outperformed it in fertilizer use efficiency by 31%. In contrast, CAP showed reduced growth and yield (by 38%) and limitations in photochemical efficiency and photosynthetic performance, likely due to significant deficiencies in potassium and phosphorus (9-fold and 2-fold lower than in HP, respectively). DCAP demonstrated strong potential to achieve similar crop outcomes to conventional hydroponics with enhanced resource efficiency. Overall, adopting the DCAP variant of aquaponics in this circular nutrition system is a promising alternative to conventional hydroponics, supporting a transition toward more environmentally resilient farming practices.