|DOLGOVSKAYA, MARGARITA - Russian Academy Of Sciences|
|VOLKOVITSH, MARK - Russian Academy Of Sciences|
|REZNIK, SERGEY - Russian Academy Of Sciences|
|MOSEYKO, ALEXEY - Russian Academy Of Sciences|
Submitted to: International Symposium on Biological Control of Weeds
Publication Type: Proceedings
Publication Acceptance Date: 12/17/2013
Publication Date: 12/2/2014
Citation: Dolgovskaya, M., Volkovitsh, M., Reznik, S., Moseyko, A.G., Milbrath, L.R. 2014. Preliminary host range assessment of Asian Chrysochus spp. (Coleoptera: Chrysomelidae), potential biological control agents of Vincetoxicum spp.. International Symposium on Biological Control of Weeds. p. 45.
Technical Abstract: The European herbaceous perennials pale swallow-wort (Vincetoxicum rossicum) and black swallow-wort (V. nigrum; Apocynaceae, subfamily Asclepiadoideae) have been the subject of classical biological control efforts, due to their invasion of various natural areas and managed habitats in the northeastern United States and southeastern Canada. Among the natural enemies known to feed upon swallow-wort species in their native range are various leaf beetles in the genus Chrysochus; the larval root-feeding stage is considered the most damaging to the plant. In addition to the widespread European/Asia Minor species C. asclepiadeus, three Asian congeners have been recorded from various swallow-wort species, as the range of the genus Vincetoxicum extends from western Europe to Japan. We assessed the host range of C. chinensis (Russian Far East), C. globicollis (Russian Far East), and C. goniostoma (southern Siberia) using a subset of test plants to determine if they should be subjected to full host range testing or rejected from further consideration. A special emphasis was placed on North American milkweeds from the genus Asclepias, a closely-related and speciose genus. No-choice tests of larvae conducted under laboratory conditions showed that all three Chrysochus species voluntarily fed and in many cases successfully developed to the adult stage on species of Vincetoxicum and, to a lesser degree, Asclepias. Chrysochus chinensis larvae also successfully developed on Cynanchum and Metaplexis spp. Adult survival and egg-production, when adults were offered test plants under no-choice conditions, generally mirrored the results of larval tests. Based on these data we are not considering these three Chrysochus species further as candidate biological control agents for European swallow-worts.