The polyvalent sequestration ability of an economically important beetle

Many specialized herbivorous insects sequester single classes of toxic secondary metabolites from their host plants as protection against natural enemies. If and how herbivores can use multiple classes of plant toxins across the large chemical diversity of plants for self-protection is unknown. We show that the polyphagous adults of the beetle Diabrotica virgifera are capable of selectively accumulating benzoxazinoids, cucurbitacins, and glucosinolates but not cyanogenic glycosides. Female beetles transfer the sequestered defense metabolites into their eggs, protecting them against generalist predators. Eggs containing a mixture of toxins are better protected than eggs with individual toxins. This work shows how herbivores can exploit plant chemical diversity to their own benefit as a novel adaptive mechanism that contributes to the structuring of multitrophic interaction networks.