Relationship between the host plant preference of the leaf beetle Ophraella communa LeSage (Coleoptera: Chrysomelidae) and distribution of feeding stimulants in asteraceous plants

Abstract

The leaf beetle Ophraella communa is an oligophagous insect that infests several asteraceous plants, especially ragweed Ambrosia artemisiifolia, in fields of Japan. The feeding responses of O. communa to methanolic extracts of 11 genera and 17 species of asteraceous plants were examined to determine whether feeding preference depended on chemicals in the plants. The methanolic extracts of 8 asteraceous species stimulated feeding in O. communa, but the other 9 species showed no activity. Two triterpenoids (α-amyrin acetate and β-amyrin acetate) and two caffeic acid derivatives (chlorogenic acid and 3,5-dicaffeoylquinic acid) are known as feeding stimulants for O. communa. The distribution of these compounds was analyzed in 17 asteraceous species. These compounds were found in many species, including nonhost plants of this beetle, however amounts and compositions differed. Even when the methanolic extracts of A. artemisiifolia were added to extracts of some species which did not elicit feeding of O. communa, the feeding of O. communa was not induced by the inactive plants. Feeding deterrents as well as feeding stimulants in the leaves of asteraceous plants appear to determine the feeding preference of O. communa.