Natural enemies of balloon vine Cardiospermum grandiflorum (Sapindaceae) in Argentina and their potential use as biological control agents in South Africa

Exploratory field surveys of the natural enemies associated with balloon vine Cardiospermum grandiflorum Swartz, an environmental weed in South Africa, Australia and other countries, were conducted in northern Argentina from 2005 to 2009. The surveys included other plant species in the genus Cardiospermum and other native Sapindaceae, permitting an assessment of the distribution and host range of the natural enemies. Seventeen phytophagous insects in five orders and ten families, and two fungal pathogens were found. The nature of the potential agents' damage, their field distribution and abundance, and the results of preliminary host-specificity testing indicated that the seed-feeding weevil Cissoanthonomus tuberculipennis (Coleoptera: Curculionidae) and the fruit-galling midge Contarinia sp. (Diptera: Cecidomyiidae) were the most promising biological control agents for C. grandiflorum outside of its native range.