Insecticide resistance in RLEM to both SPs and OPs has been confirmed in multiple populations from South Australia, Dr Umina says.
RLEM populations from South Australia, Victoria, Tasmania and New South Wales are being screened by cesar.
The research group is interested in hearing from growers or advisers who have had noted recent or past failures in paddocks that are continually needing to control RLEM with pesticides.
RLEM populations from paddocks which are frequently impacted by the mites, and often require spraying, are ideal candidates for resistance testing, Dr Umina says.
RLEM density on this site in Spring 2008 was 7,890 mites/[m.sup.2] and when we measured the density in June 2009, there was an average of 76 mites/[m.sup.2].
Table 1: Canola and ryegrass density at emergence (18/7/05) and RLEM density (15/6/05).