Prospects and challenges for classical biological control of Cactoblastis cactorum (Berg) (Lepidoptera: Pyalidae) in the US

The cactus moth, Cactoblastis cactorum (Berg) (Lepidoptera: Pyalidae), is a serious threat to native and cultivated Opuntia cacti in North America.  In the last 20 years, the moth has spread from southern Florida to the swamps of southern Louisiana.  Several methods have been implemented to manage the invasive pest including use of systemic insecticides, sanitation and removal of infested plants.  Current management options focus on long term mitigation methods such as Sterile Insect Technique (SIT) and biological control.  Increased interest in classical biological control was sparked when an apparently host specific Apanteles species has been found attacking Cactoblastis larvae in Argentina.  Preliminary studies using the Apanteles species against the cactus moth have shown promising results in laboratory conditions.  Additional studies are being conducted at the FDACS-DPI quarantine facility to evaluate host range on native non-target moth species.  This paper assesses prospects and technical challenges for the implementation of a classical biological control program against C. cactorum in the U.S.