Biology and massrearing of the buddleia biocontrol agent Cleopus japonicus (Coleoptera Curculionidae)

Cleopus japonicus (Wingelmller) was approved for release by ERMA as a biocontrol agent for buddleia (Buddleja davidii) in New Zealand in November 2005 and a massrearing programme was developed to provide the insects for the initial experimental releases. Twenty-five adults were placed in each cage (sex ratio :) with cut buddleia foliage contained in a 250 ml conical flask. Eggs are laid into purposefully-excavated cavities within the leaves and leaf buds. After one week, the infested foliage was transferred to large polyethylene storage bins and larvae reared through with fresh foliage added as required. Pupae were either left in situ or were harvested into a smaller plastic container for adult emergence. Emerged adults were transferred to Petri dishes containing cut buddleia leaves. After a maturation feeding phase ranging from 4-6 weeks, adults can be stored at 0C for extended periods. From September 2006 to April 2007, approximately 0,000 adults were produced, and multiple releases made at five experimental sites within the North Island, New Zealand. This method will be used to mass rear C. japonicus for widespread release.