Mass production, establishment and impact of Cecidochares connexa on chromolaena in Papua New Guinea

摘要

Chromolaena (Chromolaena odorata) is localised but spreading in 12 of the 20 provinces of Papua New Guinea (PNG) and the weed is becoming invasive and is expanding its range. Effort to combat and prevent its impacts on agriculture, the environment and people began in 1997 with the commencement of an ACIAR-supported biological control project. The moth Pareuchaetes pseudoinsulata has been released in eight provinces but has established only in the Markham Valley of Morobe Province where chromolaena has invaded open dry grassland environment. A second biological control agent, the stem-galling fly Cecidochares connexa, was introduced in 2001 and is being reared for field release. C. connexa has been released in eight provinces so far and is established at most release sites in these provinces. With the extension of the biological control project for a further three years, two additional agents are being considered for introduction to PNG. In this paper, we describe the techniques for mass rearing and releasing C. connexa used in PNG.