Gravel culture of the edible cactus Nopalea cochenillifera: effect of fertilizer composition on daughter cladode growth and mineral content

Many advantages are associated with hydroponic culture, including precise fertilizer management and the elimination of soil-borne diseases and weeds.
In this study, we examined the growth and mineral content of the edible cactus Nopalea cochenillifera (L.) Salm-Dyck under soil and gravel culture conditions.
In the gravel culture, plants were supplemented with 100 ppm zinc (gravel + Zn) or 500 ppm magnesium (gravel + Mg) in addition to the hydroponic fertilizer.
Growth of the daughter cladodes was significantly enhanced in the gravel culture compared to the soil culture.
The total length and number of daughter cladodes increased considerably in the gravel culture, resulting in fresh weight gains of approximately 177% (gravel + Mg) and 250% (gravel + Zn) compared to the soil culture.
We also assessed calcium (Ca), Mg, and Zn concentrations in the daughter cladodes.
Significantly higher levels of Mg and Zn accumulated in the cladodes under gravel culture with respective treatments than in the untreated cladodes and those grown in soil.
Compared to the soil culture, the Mg content in the “gravel + Mg” treatment increased by approximately 147%, while the Zn content in the “gravel + Zn” treatment increased by approximately 1,600%. However, the Ca levels in the gravel culture were notably lower than in the soil culture.
These findings suggest that gravel culture effectively enhances the growth and biofortification of N. cochenillifera.

XI International Congress on Cacti as Food, Fodder and Other Uses

T. Horibe, S. Tsuchimoto

biofortification, heavy metals, hydroponics, Opuntia

https://doi.org/10.17660/ActaHortic.2026.1452.13