Aquaponics substantially improved sweetpotato (Ipomoea batatas) slip production compared to soil but decreased phenol and antioxidant capacity

A major bottleneck to sweetpotato (Ipomoea batatas) storage root production is obtaining enough slips, which are the initial planting material. Some evidence suggests aquaponics can yield more plants than in soil, but none is available on slip production. In this study, the growth, mineral composition, total phenol, and antioxidant capacity in I. batatas cuttings were compared when grown aquaponically or terrestrially in soil. The aquaponic system housed catfish that were fed twice daily while soil-grown I. batatas cuttings received daily applications of a commercial fertilizer. Results showed that from nine I. batatas cuttings, these became nine slips in soil after 3 weeks compared to 55 slips in the aquaponic system. The mean length, weight, and number of nodes were all significantly higher (p < 0.05) in aquaponics while the stem diameters were similar between treatments (p > 0.05). Both the total phenol and antioxidant capacity in the I. batatas leaves were significantly higher in soil. Manganese and zinc were both significantly higher in leaves when grown aquaponically, but no significant difference in iron, phosphorus, or magnesium was detected. Results demonstrate that aquaponics provides vastly superior I. batatas slip production, but the implications of the altered mineral composition and total phenol/antioxidant when the slips are later planted in soil should be explored.

Automated summary

The study found that aquaponics significantly improves sweetpotato slip production, resulting in a higher number of slips compared to soil cultivation. However, the altered mineral composition and total phenol/antioxidant capacity in slips grown aquaponically may have implications on their subsequent growth when planted in soil.