Khapra beetle is high on the watch list for exotic pests and diseases for Australia given the economic impact it could have on the industry. Presence of the pest can result in 75 per cent loss of product.
If the pest were to establish in Australia, it could have detrimental impacts on our export orientated grain industry. Many countries maintain quarantine restrictions against possible importation of this pest and prevent market access for infested produce.
Treatments are available but difficult to implement effectively, as larvae can maintain a state of very low metabolic activity and are extremely resistant to contact insecticides during this period. Because of this, larvae can exist in a hibernation state for two years or more under some conditions.
In 2007, Khapra beetle was detected in personal belongings arriving in Perth from overseas. A rapid response under the Emergency Plant Pest Response Deed saw the infested home covered in a shrink-wrap sheeting that was gas proof and fumigated using methyl bromide. This is the only viable and internationally agreed treatment for Khapra beetle. Successful eradication was declared in 2009, following evidence from trapping surveillance that included over 1,000 trap inspections from nine different sites. The eradication was successful because of the speed at which the Khapra beetle was detected and reported. South Australia also had an incursion in 2016, which was successfully eradicated.
In both cases, being able to quickly identify an incursion to mount an eradication program is the most effective way of dealing with Khapra beetle.
To be on the front foot, the Victorian Government established the Sentinel Silo Surveillance program. The program has been running since 2016 and includes 40 specialised pheromone traps set up next to grain storage silos across 12 sites.
The pheromone traps are designed to attract the Trogoderma species, because there are native Trogoderma species, any unidentifiable samples are sent to the Agriculture Victoria diagnostic team at AgriBio, Centre for AgriBioscience in Melbourne.