Poster Presentation Science Protecting Plant Health 2017

Combining insect pheromones and fungal volatiles for improved field monitoring of the rusty grain beetle Cryptolestes ferrugineus (Stephens) (Coleoptera: Laemophloeidae) (#259)

Mark M Stevens 1 2 , Rachael M Wood 1 2
  1. NSW Department of Primary Industries, Yanco, NSW, Australia
  2. Plant Biosecurity Cooperative Research Centre, Bruce, ACT, Australia

High levels of resistance to the fumigant phosphine have led to increased interest in the ecology of the rusty grain beetle (RGB) both within and outside the grain storage environment. The capacity to monitor flight activity and trap RGB in the field will allow predictive models to be developed to minimise risk during grain handling operations, and also provide material for traditional and DNA-based resistance monitoring.

We used Lindgren funnel traps to evaluate ten synthetic volatiles as potential attractants for RGB, and found 1-octen-3-ol and 3-octanone to both be effective. Both compounds are known to be produced by fungi and both showed a positive correlation between volatile release rates and trap captures, with 1-octen-3-ol being the most potent attractant. The CryptoLureTM, the only commercial pheromone-based lure available for RGB, was significantly (P < 0.05) less effective than 1-octen-3-ol, however significantly more RGB were trapped when a CryptoLureTM was combined with 1-octen-3-ol on an individual trap than when 1-octen-3-ol was used alone.

Trap comparisons showed that panel traps were more effective than Lindgren funnel traps for capturing RGB with the combined attractants, and this is attributed to the higher volatilisation rate of 1-octen-3-ol from this trap design. Rubber septa impregnated with 1-octen-3-ol were equally as effective as glass dispenser vials when both were deployed with CryptoLuresTM on Lindgren funnel traps over a five-day trapping period. Whilst 1-octen-3-ol can be used alone to effectively monitor RGB flight activity, a two-part attractant consisting of a CryptoLureTM and a separate rubber septum impregnated with 1-octen-3-ol will provide increased trapping efficiency.