Ms Aston Arthur, PhD Candidate , Dr Andrew Weeks
Funded by the Grains Research and Dvelopment Corporation.

Balaustium and Bryobia mites have recently been identified as potential emerging pests within the Australian agricultural industry. The damage caused by these mites in Australia has increased in the last decade, with reports indicating that these mites have caused extensive damage to a variety of crops and pasture. Despite the potential of these mites to cause damage there is little information known about their biology and control worldwide, therefore making it difficult to devise effective and sustainable control strategies. This research project aims to address this by gaining some insight into the basic biology and ecology of these mites. The areas of research that will be conducted on these mites include their lifecycle, seasonal abundance patterns, plant host range, distribution, pesticide tolerance, pest status and population biology. DNA sequence data will also be used to identify any different species/strains of Balaustium and Bryobia mites. Findings from this ongoing study have shown that both Balaustium and Bryobia mites have a high natural tolerance to a range of currently registered pesticides against earth mites. This suggests that these mites may prove difficult to control in the field. Results from the seasonal abundance study have shown that these mites go through at least 2 generations a season and are found from March until December, with numbers generally peaking around spring time. Distribution collections throughout southern Australia have shown that Balaustium mites are restricted to the southern coastal areas and do not occur too far inland, whereas Bryobia mites are much more widespread. A plant host experiment has shown that these mites cause a considerable amount of damage and are able to persist on a variety of different crops. Preliminary results using the amplified fragment length polymorphism (AFLP) technique have indicated that Balaustium mites reproduce asexually and have a limited amount of genetic variation.