Australian scientists have confirmed the Russian Wheat Aphid (RWA) now established in parts of the nation’s south-eastern cropping regions is a single biotype.
This new knowledge, achieved through research investments by the Grains Research and Development Corporation (GRDC), will underpin ongoing and future research efforts aimed at combating the cereal crop pest which was first detected in SA in 2016.
Experiments to identify the biotype or biotypes of the aphid in Australia and possible origin of the incursion have been led by entomologists Maarten van Helden and Greg Baker from the SA Research and Development Institute (SARDI), a division of Primary Industries and Regions SA (PIRSA).
Dr van Helden says the virulence profile of RWAau1 is nearly identical to the American RWA1 biotype, which suggests the origin of the incursion in Australia is either America or the same origin as the original RWA1 that was first detected in Colorado in 1986.
“Not only does this information help to identify the most likely geographical origin of the aphid and the possible incursion pathway, but it also enables identification of the plant resistance genes that could be used by breeders to develop new resistant cereal varieties,” Dr van Helden said.
The experiment, which took place at the Waite Campus in Adelaide, involved almost 7000 plants that were infested with aphids.
Dr van Helden said the results showed no significant differences in the virulence profile among the 15 clones toward the 24 cereal accessions.