nematicidal isochromane glycoside from kigelia pinnata leaves

Synthetic nematicides such as oxamyl and carbofuran play significant roles in the management of plant-parasitic nematodes. However, their negative environmental impacts have it imperative to search for safer alternatives. As part of our contribution in the search for bio-nematicides, compounds from plant extract were screened for possible potent nematicidal agent. A new isochromane carboxylic acid glycoside, isolated from the leaves of Kigelia pinnata (Lam.) Benth (Bignoniaceae) was evaluated for its nematicidal activity. The structure of the proposed compound was characterized by various spectroscopic methods, which included UV, FTIR, 1D-, and 2D-NMR, FAB-MS, TOF-ESI-MS and TOF-ESI-MS/MS (TANDEM). The in vitro experiment conducted on the glycoside against Meloidogyne incognita juveniles and eggs indicated an induced mortality. Its activity can be compared favourably with oxamyl, when tested at 0.1 mg/mL concentration. At four hours of observation, no significant difference (P < 0.05) between oxamyl and the glycoside was observed. The present data sustains that natural glycoside is a promising oxamyl alternate for controlling nematode-induced plant root knots and may contribute to integrated pest management.