Jing Li and her team under the supervision of Danny Geelen, discovered that water extracts of the Belgian endive forced roots (Cichorium intybus var. foliosum) exert consistent biostimulant activity over two consecutive harvest years when applied to plants.

The shoot and the primary root of in vitro cultivated Arabidopsis thaliana treated with Belgian endive extracts were 30% increased in size compared to plants grown under control conditions. The ornamental species Plectranthus esculentus also showed enhanced in vitro shoot and root growth, suggesting bioactivity on a broad range of species. Fractionation of the Belgian endive extracts into aqueous and organic subfractions coupled with bioactivity measurements showed that the principal root and shoot growth-promoting bioactive molecules are primarily water-soluble. A recent experiment demonstrated a 40 % of yield increase in bell pepper under greenhouse conditions upon root application with Belgian endive extract.

Belgian endive is a popular crop in Europe, with Belgium accounting for 95% of the world’s production. This biannual crop is grown for its etiolated leaves, which are produced from the forced roots to sprout in the dark for 21 days. Belgian endive roots as a byproduct are thus available year-round. Currently, the roots are valorized as feed.

This research was conducted in collaboration with researchers of ILVO and the financial help of FWO. The project results were consolidated in a patent, recently published under the number WO2022218984. Companies with a commercial interest in the patent, please contact Maaike Perneel.