Aquaponic cultivation of pearl millet (Pennisetum glaucum L.), finger millet (Eleusine coracana L.), and quinoa (Chenopodium quinoa L.) for sustainable food and fodder production

This study investigated the potential of aquaponics, a sustainable food production method that integrates aquaculture and hydroponics, for cultivating pearl millet, finger millet, and quinoa irrigated with effluent from a tilapia aquaculture unit. Conducted over a six-month period, the experiment utilized a pilot-scale backyard aquaponics system, with tilapia metabolic waste serving as the primary nutrient source. Plant growth performance, yield, and the proximate and mineral composition of grains and leaves were assessed over the experimental period. The system maintained water quality parameters within optimal ranges for both tilapia culture and plant growth throughout the six-month experimental period. Tilapia exhibited a high survival rate (86–88%) accompanied by substantial growth, reaching a final mean weight of approximately 350 g. Among the crops evaluated, quinoa and pearl millet produced the highest grain yields (1,218 g and 1,185 g, respectively). Nutritional analysis indicated that grains from all crops possessed favourable nutritional profiles, with quinoa exhibiting higher protein content and pearl millet showing elevated antioxidant levels. The research study highlights the aquaponics potential to enhance both fish production and grain production with nutritional quality, thereby contributing to sustainable food and agriculture production practices through efficient nutrient utilization.