Crops across South Australia are playing host to a large number of redlegged earth mite (RLEM).
Primary Industries and Regions SA has reported significant crop damage in many areas as the mite may become more resistant to insecticide.
The pest is causing damage in the lower Eyre Peninsula with the paddock edges and sandy rises most affected, while in the Mid North it is travelling through road verges to get to crops.
The mite has been found in lentil plantings on the Yorke Peninsula while significant numbers have been located in pastures in the South East.
Damage has also been found in Mallee barley crops, around Cooke Plains and Coombe, especially those which were sown late in the season.
Kangaroo Island is hosting major numbers of RLEM in pasture, cereal and bean crops. According to PIRSA the high number of mites across the State has been due to synchronous hatching which was possible because of climatic conditions.
A free service is available to South Australian grain growers who surmise there has been a failure in chemical control of the mite or if they suspect there is some insecticide resistance.
The service, provided by cesar and funded by the Grains Research and Development Corporation (GRDC), will help find resistance before it spreads and suggest the best options.
PIRSA also suggests farmers should consider following the RLEM management strategy to help control the spread of the mite, which can be found at https://grdc.com.au/resources-and-publications/all-publications/factsheets. The strategy reports genetic analysis of mite populations has shown insecticide resistance has evolved on more than one occasion.
For more information or to access the testing service contact Aston Arthur on 0427 875 040 or email firstname.lastname@example.org