Management of six-spotted mite in WA avocado orchards – phase 2 (AV19002)
What’s it all about?
This investment is delivering effective options for the integrated pest management (IPM) of six-spotted mite in avocado orchards. Beginning in 2019, it follows previous levy-funded project Pest status and management of six-spotted mite (Eotetranychus sexmaculatus) in WA avocado orchards (AV15012), which sought to assist growers in monitoring mite populations and implementing appropriate management techniques, as well as investigating the role that predatory mites could play during production. The project team produced the Monitoring for six-spotted mite in avocado orchards guide and laid the groundwork for this phase two investment to further industry understanding of how to manage the pest.
In order to develop a comprehensive IPM plan for growers – which will be extended via demonstration sites, online materials and articles in the levy-funded Talking Avocados – the research team will be investigating:
- The use of mass-reared predatory mites as a form of six-spotted mite management
- The role of naturally occurring predatory mites
- The relationship between tree health, mite numbers and leaf fall
- Chemical application recommendations based on resistance management, impact of chemicals on beneficial species, and the impact that timing and/or application methods have on the level of pest mite control.
Spring and early summer is the peak season for mite activity in avocado orchards in Western Australia and is when much of the field assessments and trials take place. This past season the assessments focused on; the relationships between leaf nitrogen, pest mite numbers and defoliation; using releases of the predatory mites A. lailae or a pollen prey mite mix for six-spotted mite control and assessing the effectiveness of sprays oils through a case study and review of practices overseas.
The fortnightly monitoring of orchard blocks has continued and another season of results. This data has contributed to a number of case studies on effective and sustainable use of miticides, provided further data on the relationship between six-spotted mites and predatory mites, and led to early recommendations around SSM numbers in autumn and the use of miticides then.
In the final six months of the project, the results from the last season’s field assessments will be analysed. The results of these, along with feedback from growers, will feed into the extension activities and materials to be developed at this time. Work has already commenced in these areas.
The project’s first spring in 2020 allowed for many of the targeted field trials and intensive monitoring activities to take place.
Initial results showed a high degree of variability in six-spotted mite (SSM) numbers at all orchard levels – from within trees to between trees, between blocks and between orchards – highlighting the need for growers to closely monitor their orchards. The data collated will be further analysed over the coming months.
The project team are working closely with other local and international researchers, including two pest management-related projects in the Hort Innovation Avocado Fund: Review and extension of avocado pests and their management (AV19001) and Monitoring avocado quality in retail (AV19003).
While COVID-19 restrictions impacted some planned international travel, alternate strategies were put in place and the affected work is now progressing well.
The team’s results and insights have been shared with industry via a grower day presentation and an article that will be published shortly in the Talking Avocados magazine. Information will continue to be shared as work progresses.
This project is a strategic levy investment in the Hort Innovation Avocado Fund