An investigation of the responses of herbivores to cyanogenesis in Lotus corniculatus L.

In laboratory feeding choice experiments several species of insects and molluscs eat acyanogenic Lotus corniculatus leaves or petals in preference to cyanogenic alternatives. These species can be characterized as generalist feeders for which L. corniculatus forms only an occasional dietary item for any particular individual. Some of the insects that were found to display selective eating were maintained on exclusive diets of either cyanogenic or acyanogenic L. corniculatus. Survival times varied considerably between species, but there was no evidence that mortalities were higher amongst the groups exposed to cyanide. These results suggest that the major role of cyanogenesis may be as a feeding inhibitor, not as a toxin.