Looking to the past, monitoring the present, securing the future: Resistance to the grain fumigant phosphine

Associate Professor Paul Ebert from UQ's School of Biological Sciences will present a QAAFI Science Seminar, titled 'Looking to the past, monitoring the present, securing the future: Resistance to the grain fumigant phosphine' 

The fumigant phosphine has been used extensively since the 1980s to protect the vast majority of our grain harvest from insect pests. Since the international ban on methyl bromide use for all but quarantine purposes as of 2005, our grain storage system has essentially been dependent on a single molecule for insect control. Strong resistance to phosphine was discovered in 1997 in Millmerran, Queensland. I became aware of the problem in 1999 and thus began a long and productive collaboration with the Queensland Department of Agriculture (DAF) and Fisheries. This work led to the identification of 2 primary genetic factors that are responsible for strong resistance in every outbreak, in every grain pest species on every continent that we have examined. We have used this knowledge to develop a high-throughput resistance monitoring system that we have deployed across the eastern grain-growing regions of Australia and across India as well. We are now deploying this resistance monitoring system at central grain storage facilities in Queensland to determine the effects of standard pest management practices on the resistance allele frequency. We have used our identification of the resistance genes to explore the mechanism of action of phosphine. We have used our understanding of the action of phosphine to identify soluble compounds and gases that synergistically enhance the toxicity of phosphine. Understanding the molecular basis of the synergistic interaction has now become the primary focus of my laboratory. Our goal is to be proactive and to continue to work closely with DAF, so that we are prepared for resistance problems that might eventuate in future.

Associate Professor Paul Ebert is an academic at the School of Biological Sciences, The University of Queensland.