Where to from here?
- Encourage careful monitoring of soil moisture management and recommend growers trial strategic timing of nitrogen application.
- The value of cross-pollinisers needs to be further investigated in the South-West of Western Australia. This should include investigation of flowering timing for pollination potential and visitation habits of pollinators to different flower stages and different trees with different flower intensity.
- Investigations into the use of GA3, to determine capacity to modify flowering intensity, timing of flowering and shoot flush. This will require better knowledge of the timing of the various stages of floral development.
- Investigate further the timing of spring vegetative flush, what may cause seasonal variations in this timing and the impact of this on flowering and fruit set. Further investigate potential options to modify the timing of the vegetative flush if shown as useful.
- Investigate the setting of fruit, what climatic conditions coincide with fruit set and determine if late setting fruit is subject to increased immature fruit drop.
Other resources
Further reviews on the issue of alternate and irregular bearing have been commissioned by Avocados Australia. The reports are available via the Avocados Australia website (member services login required).
Presentations have been delivered on pollination and fruit set and alternate and irregular bearing as part of Avocado Study Groups and Qualicado workshops. Copies presentations are available via Avocados Australia's Best Practice Resource (password login required).
Acknowledgements
Special mention must be made of Dr Cengiz Erol who greatly assisted in the collation and review of the research literature on this subject.
This publication was previously published as Appendix G in ‘Improving technology uptake in the WA avocado industry’, a final report for Horticulture Australia Limited project AV06002. This was funded by the Agricultural Produce Commission — Avocado Growers Committee, Horticulture Australia Limited and the Department of Agriculture and Food, Western Australia. The complete final report is available electronically via Avocados Australia website (member services login) or Horticulture Innovation Australia.
References
Most of the following references and many more are available electronically via avocadosource.com, an extensive internet database of avocado information from around the world — hosted by the Hofshi Foundation.
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