EVALUATION OF EXOTIC SOLANUM SPP. (SOLANALES: SOLANACEAE) IN FLORIDA AS HOST PLANTS FOR THE LEAF BEETLES LEPTINOTARSA DEFECTA AND L. TEXANA (Coleoptera: Chrysomelidae)

Abstract

Tropical soda apple, Solanum viarum Dunal, wetland nightshade, S. tampicense Dunal, and turkey berry, S. torvum Swartz, are considered three of Florida’s most invasive plant species. These nonnative perennial broadleaf weeds are disrupting native plant communities in agricultural areas and natural ecosystems. The lack of natural enemies in Florida is thought to be an important factor contributing to their invasiveness. The North American leaf beetles Leptinotarsa defecta (Stål) and L. texana (Schaeffer) that attack silverleaf nightshade, Solanum elaeagnifolium Cav., a native congener of the three nonnative solanums, were evaluated for their potential as biological control agents. The suitability of tropical soda apple, wetland nightshade and turkey berry as host plants for the native Leptinotarsa beetles was studied in a quarantine laboratory using single plant and paired plant tests. Neonate larvae of L. defecta developed to the pupal stage only on their natural host plant silverleaf nightshade. Feeding damage on turkey berry and wetland nightshade was negligible and no feeding occurred on tropical soda apple. In contrast, development and reproduction of L. texana on the nonnative turkey berry were comparable with silverleaf nightshade. These results suggest the nonnative turkey berry may be included in the potential host range of the native silverleaf nightshade beetle L. texana.