The ability of isothiocyanates to suppressGlobodera pallidawas evaluated throughin vitroassays. Several isothiocyanates increased juvenile mortality, the most effective being allyl isothiocyanate, which caused 100% mortality at both 25 and 50 ppm after 72 and 24 h exposure, respectively. In a hatching assay, allyl isothiocyanate was able to suppress hatch; in addition, replenishing allyl isothiocyanate every 3 days increased hatch suppression, and viability staining indicated that egg mortality was increased. Allyl isothiocyanate above concentrations of 50 ppm significantly affected both hatch suppression and mortality. Differing effects of isothiocyanates onG. pallidasuggest that their toxicity depends on the pest of interest and this study shows that allyl isothiocyanate is a good candidate for the control of potato cyst nematodes using biofumigation.
