INHIBITION OF POTATO CYST-NEMATODE HATCH BY LIGNANS FROM BUPLEURUM-SALICIFOLIUM (UMBELLIFERAE)

A series of lignans from Bupleurum salicifolium Soland (Umbelliferae) were tested for nematostatic activity on the cysts and freed second-st age juveniles of the potato cyst nematodes Globodera rostochiensis and G. pallida. None of the six lignans tested-bursehernin, matairesinol, syringaresinol, the novel product buplerol, guayarol, and a derivativ e, nortrachelogenin triacetate-showed nematicidal activity in an in vi tro analysis with second-stage juveniles, but significant differences were noted when the lignans were assayed for nematostatic activity as cyst hatching inhibitors. Bursehernin and matairesinol showed the grea test activity, at concentrations of 50 ppm. This is the first known in stance of a natural product inhibiting the hatch of the nematode G. pa llida. The HID (hatching inhibiting dose) of bursehernin was estimated , and some conclusions were drawn about the structure-activity relatio nships of the lignans under study.