Efficacy of methyl bromide used at reduced rates to control larvae and adults of goldenhaired bark beetle Hylurgus ligniperda

Abstract

Pine (Pinus radiata D Don) logs exported from New Zealand must undergo fumigation to ensure they are free of phytosanitary insects to meet the requirements of importing countries The goldenhaired bark beetle Hylurgus ligniperda (F) is one of the major hitchhiker species that can infest New Zealand pine logs Adults and larvae can be present in the bark and cambium layer of freshly cut logs To examine ways of reducing rates of methyl bromide fumigation diet containing both life stages (extracted from pine logs) was exposed to 0 49 or 73 g/m³ methyl bromide for 16 h in 28litre fumigation chambers at 5 10 15 or 20C Both the 49 g/m³ and 73 g/m³ methyl bromide exposures resulted in 100 mortality at all temperatures Average mortality among controls was larvae 7 adults 23 The results indicate that the present methyl bromide fumigation rates used for pine logs exported from New Zealand could be reduced