Author(s): Bernardino, Raul ; Vieira, Judite ; Vaz, Daniela C. ; Santos, Ounísia D. ; Ribeiro, Vânia S. ; Pires, Cristiana L. ; Cotrim, Luís ; Bernardino, Susana
Date: 2025
Persistent ID: http://hdl.handle.net/10400.8/14813
Origin: IC-online
Subject(s): Clarias gariepinus; Environmental sustainability; Insect-based feed; Mentha pulegium; Petroselinum crispum; Plant growth; Mineral profile
Insects can be used as alternative protein/food sources. Here, a novel aquaponic system based on the African catfish (Clarias gariepinus) fed with 30% of yellow mealworms (YM) (Tenebrio molitor) as substitute feed to 100% of fish meal (FM) was employed to produce parsley (Petroselinum crispum) and pennyroyal (Mentha pulegium). The two systems implemented (30YW/70FM and 100FM - control) showed identical water quality parameters. The 30YW/70FM operation led to a reduction by 27% of the carbon footprint, relatively to the 100FM system. Plants cultivated in the 30YW/70FM aquaponic system led to lower plant biomass (↓∼75%), as stated by the statistically significant (p < 0.05) lower values of “plant height”, “foliage diameter”, “leaf number”, “biggest leaf length” and “root length”. Moreover, 100FM parsley showed higher levels of greenness (100%) and health status (97%) than the 30YW/70FM plants (↓50% greenness; ↓20% health status). Likewise, 100FM pennyroyal also showed higher levels of greenness (100%) and health status (100%) than 30YW/70FM pennyroyal (↓56 % greenness; ↓59% health status). Also, even if all plants presented equivalent levels of P, K, Ca and Fe, the plants grown in the 30YW/70FM system showed some Cl-accumulation (>7.0 g Cl.kg−1 for parsley and > 4.0 g Cl.kg−1 for pennyroyal, in dry weight) in the leaves and Cu and Mn accumulation in the roots (> 0.4 g.kg−1 in dry weight). The presence of high concentrations of Cl in T. molitor, and consequently in the water and fish faeces, might have caused some abiotic stress and toxicity to plant tissues, reducing plant growth.
