Mass trapping of Coryphodema tristis (Lepidoptera: Cossidae) using a sex pheromone in Eucalyptus nitens compartments in Mpumalanga, South Africa

Abstract

Coryphodema tristis (Lepidoptera: Cossidae) is a native wood-boring moth with a broad host range on both native and non-native vegetation and is an important pest of commercial Eucalyptus nitens plantations in South Africa. Management of C. tristis is challenging since the larvae spend the majority of their lifecycle tunnelling within the wood of host trees. Following the development of a synthetic sex pheromone for C. tristis, pheromone-based mass trapping of male moths was investigated as a tool to control the pest. More than 5 000 pheromone-baited yellow bucket funnel traps with extensions were deployed in E. nitens stands in 2016 and 2017. Evaluation of the efficacy of the mass trapping programmes was done in 2017 and 2018 through the destructive felling of infested trees and comparison of the ratio of new to old C. tristis colonies in trapped and non-trapped compartments. The results show a significant decrease in the ratio of new to old colonies in trapped compartments compared to non-trapped compartments. This study shows that the large-scale trapping of C. tristis using a synthetic sex pheromone is a viable management strategy to control C. tristis.