Nematicidal activity of Echinacea species on the root‑knot nematode Meloidogyne incognita

Echinacea species are reported for a large content of bioactive compounds, but their effects on phytoparasitic nematodes are still unknown. This study comparatively investigated the in vitro activity of chemically characterized extracts from E. angustifolia, E. pallida and E. purpurea on juveniles and eggs of the root-knot nematode Meloidogyne incognita. Suppressiveness of soil amendments with Echinacea plant biomasses was also investigated against M. incognita on tomato in potting mixes. More than 50% juvenile mortality occurred after a 48-h exposure to a 500 μg mL−1 solution of all Echinacea extracts, as well as more than 50% of M. incognita eggs did not hatch after a 1-week exposure to the same concentration of E. angustifolia extracts. Nematode multiplication on tomato roots was always significantly reduced in soil amended with all Echinacea biomasses, as well as almost all treatments also resulted in a significant tomato growth increase. Polar compounds such as echinacoside and chicoric acid were the main components of the extracts from Echinacea aerial parts, whereas apolar components as alkamides prevailed in root extracts. Data confirmed the potential of the three Echinacea species, mainly E. angustifolia, for the formulation of new formulates for a sustainable nematode management.