Ground Cover Supplement : GC Supplement - Grain storage
GROUND COVER GRAIN STORAGE 8 SURVEILLANCE & MONITORING IF A GRAIN storage insect wants to find another, especially a mate, it uses its highly sensitive olfactory receptors to sniff out the pheromones released by other insects. Researchers are now combining a range of disciplines to develop a biosensor, the Cybernose®, to sniff out pests in stored grain. A biosensor is a device for detecting and measuring very small quantities or changes in a biochemical or chemical substance such as insect pheromones. Researchers at CSIRO Food Futures Flagship in collaboration with researchers at the South Australian Research and Development Institute are working on this CRC for National Plant Biosecurity project. The project hopes to deliver a range of Cybernose® devices suited to identifying the presence of grain storage pests. The use of a Cybernose® for stored grain pests is a spin-off from a CSIRO project to develop a biosensor with a range of applications including the measurement of wine aroma, monitoring for food safety and detecting explosives. There are strong synergies between the CRC collaboration and CSIRO's broader research in this area. The research team is developing knowledge of olfactory (scent organ) receptors of grain pests, in particular red flour beetle (Tribolium castaneum). Commencing in September 2009, the initial part of the project is focused on finding receptors in the red flour beetle that respond to known pheromones. For example, insects have a very sensitive system for detecting sex pheromones, so receptors are dedicated to that purpose. By using a biosensor fitted with the receptors that detect the sex pheromones researchers would be able to identify the presence of red flour beetle in stored grain. One of the two postdoctorates working on this project, Dr Bradley Stevenson, is using an olfactometer to test what chemicals attract the insect. Air carrying different chemicals is blown down two arms of a Y-shaped tube. Insects are introduced at the bottom of the Y and make their way up the tube. When they make a choice at the junction, information on the volatiles that are attractive to red flour beetle is gathered. Electrophysiology, measuring the change in electrical signal in the insect's antennae when exposed to different odours, is another method being used. This technique identifies an insect's ability to detect an odour. An insect can only identify an odour if it has the receptors for that odour. There are several practical ways in which this research might be useful to industry. Essentially, air sucked off the grain and passed through a biosensor would enable an entire silo to be sampled at once. For example, in an aerated silo, a biosensor might be incorporated in the aeration system, so the air is continually sampled and checked for insects. A second option would be to sample air from the end of the auger or spear used to collect grain for sampling. If the biosensor detects there might be insects present a grain sample could be gathered from that part of the storage, rather than taking blind, random samples. Current research to identify and isolate the biological receptors will end in 2012. However, it will probably be a minimum of six or seven years before a working prototype will be available in the grains industry. □ GRDC Research Code NPB00004 (CRCNPB project CRC20081) More information: Dr Alisha Anderson, CSIRO Entomology, 02 6246 4181, firstname.lastname@example.org; www.grdc.com.au/NPB00004 An insect can only identify an odour if it has the receptors for that odour. Measuring the change in electrical signal in the insect's antennae when exposed to different odours identifies an insect's ability to detect an odour. PHOTO: CSIRO SNIFFING OUT INSECTS A biosensor to smell the presence of grain pests is being developed -- but don't hold your breath, it's at least six years away By Alisha Anderson A BIOSENSOR WOULD ENABLE AN ENTIRE SILO TO BE SAMPLED FOR INSECT PESTS.
GC Supplement - Biosecurity
GC Supplement - Climate