ARS | Publication request: The cactus moth, Cactoblastis cactorum: Lessons in Biological Control

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: June 3, 2012
Publication Date: N/A

Technical Abstract: The cactus moth was one of the success stories in classical biological control. In the 1920s, the prickly pear cactus was a serious pest in Australia. The cactus moth was imported from its native habitat in South America and proved so successful in controlling cactus that it was mass reared and exported to other countries, including Caribbean islands. In 1989, the moth was discovered in Florida where it threatened ornamental and rare species of cactus. Since then, the moth has spread to several states and is making its way towards the desert southwest, threatening the US cactus industry. Computer models indicate that climatic conditions are favorable for the moth to extend its geographic distribution into Mexico where cactus is an important cultural and economic plant species. Unfortunately, the successful biological control agent had become a serious pest. Despite decades-long scientific interest in the moth, no detailed biological studies were conducted, prior to those reported here. We conducted detailed studies on insect life history at different constant temperatures in the laboratory. Field studies identified three distinct generations in Florida. Our laboratory and field studies suggested the egg stage was vulnerable to control. We evaluated ants as egg predators and wasps as egg parasites. An insect pathogen was also tested as a potential control agent. Effective area-wide management strategies will be needed to prevent serious economic loss to the cactus industries of the US and Mexico.