188 Session 4 Target and Agent Selection

Abrostola clarissa (: ), a New Potential Biological Control Agent for Invasive Swallow-Worts, Vincetoxicum rossicum and V. nig r um

M. Dolgovskaya1, M. Volkovitsh1, S. Reznik1, V. Zaitzev1, R. Sforza2 and L. Milbrath3

1Zoological Institute RAS, 199034, St.Petersburg, Russia, Russian Biocontrol Group [email protected] 2USDA-ARS-EBCL, Montferrier sur Lez, France 3USDA-ARS, Ithaca, New York, USA

Abstract

Pale and black swallow-worts (Vincetoxicum rossicum (Kleopow) Barbar. and V. nigrum (L.) Moench; Apocynaceae, subfamily Asclepiadoideae), perennial vines native to Eurasia, are now invading natural and anthropogenic habitats in the northeastern U.S.A. and southeastern Canada, threatening natural biodiversity and increasing control costs for land managers. Chemical and mechanical methods have not been adequate to control swallow- worts. In addition, no local American herbivores or pathogens cause significant damage to these weeds. Several potential biological control agents associated with Vincetoxicum spp. in Europe have been found and investigated, but none of them have yet been introduced. During explorations for herbivorous feeding on Vincetoxicum species in the Russian North Caucasus, we discovered a new potential biological control agent, Abrostola clarissa Staudinger (Lepidoptera, Noctuidae). A. clarissa inhabits low mountains and dry hills, having 1 – 2 generations per season. The biology of this species is similar to that of the closely related A. asclepiadis: eggs are laid on the undersurface of the host plant leaves, and larvae feed on the foliage and pupate in the soil. In natural conditions, larvae of this noctuid were collected only on Vincetoxicum spp. No-choice tests conducted under laboratory conditions showed that larvae of A. clarissa voluntarily fed and successfully pupated on Vincetoxicum nigrum, V. rossicum, V. hirundinaria (L.) Pers., and V. laxum (Bartl.) C.Koch. Neither feeding nor survival was recorded on other Apocynaceae (11 species of Amsonia, Apocynum, Asclepias, and Cynanchum) or on plants from other, more distantly related, families (Rubiaceae, Scrophulariaceae, and Convolvulaceae). We conclude that A. clarissa can be considered a highly specific potential biological control agent that undoubtedly deserves further study.

XIII International Symposium on Biological Control of Weeds - 2011