Delphastus catalinae and Coleomegilla maculata lengi (Coleoptera: Coccinellidae) as biological control agents of the greenhouse whitefly, Trialeurodes vaporariorum (Homoptera: Aleyrodidae)

Predation efficacy and compatibility of the predatory lady beetles Coleomegilla maculata lengi Timberlake and Delphastus catalinae (Horn) against the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) were studied in laboratory on glabrous fuchsia (Fuchsia hybrida Voss cv Lena Corolla) and pubescent poinsettia plants (Euphorbia pulcherrima Willd ex Klotzch cv Dark Red Annette Hegg). On glabrous plants (fuchsia), fourth-instar and adults of C maculata were the most efficient, both against whitefly eggs and pupae. On pubescent plants (poinsettia), the larger stages of C maculata were negatively affected and less efficient than adults of D catalinae. The presence of plant structure did not affect the voracity of either predator species. Finally, the simultaneous use of both predator species generated inter-specific competition. These results provide recommendations for biological control of whitefly in horticultural greenhouses.