Constitutive flavonoids deter flea beetle insect feeding in Camelina sativa L.

Extracts of quercetin glycosides from three-week old leaves of Camelina sativa were tested for their effects on crucifer flea beetle feeding. The extract fractions moderately deterred flea beetle feeding in mixtures containing rutin, but not when the glycosides were presented as individual compounds. Leaves and cotyledons of C. sativa contain large amounts of quercetin glycosides. In contrast, Brassica napus leaves and cotyledons contain only traces of quercetin glycosides, while leaves accumulate large amounts of kaempferol glycosides. The results suggest that quercetin glycosides form part of the arsenal of C. sativa chemical defenses against flea beetles, and that B. napus is devoid of this form of defense.