Potential distribution of Leptospermum species (Myrtaceae) in Australia for bioactive honey production purposes

ABSTRACT

The genus Leptospermum (Myrtaceae) is widespread in Australia and contains several species that are of increasing interest to produce bioactive honey. Here, we used the Maxent algorithm to investigate bioclimatic, climatic, and soil variables as predictors for potential distributions of seven Leptospermum species that have been identified as useful for bioactive honey production in Australia (L. lanigerum, L. liversidgei, L. nitens, L. polygalifolium, L. scoparium, L. speciosum, and L. whitei). Bioclimatic and climatic variables, mainly those related to moist conditions, were the best predictors for the distribution of the species. Leptospermum lanigerum and L. scoparium were suitable species in areas in southwestern Australia and Tasmania, while L. polygalifolium was suitable for eastern Australia. For L. nitens, appropriate areas were found only in western and southern regions, whereas only border ranges in Queensland and New South Wales were considered suitable for L. liversidgei, L. speciosum, and L. whitei. Notably, the latter areas were identified as a potential ‘hotspot’ for Leptospermum species. Our study can assist the incipient Leptospermum honey industry in Australia in identifying suitable local species and the local maintenance requirements for the species chosen.

KEYWORDS:

• Manuka honey
• modelling
• climate
• environmental niche
• geographical range

Acknowledgements

We thank The University of Adelaide who provides ArcGIS software access. We are grateful for the free database and software resources used in this study: Atlas of Living Australia, CSIRO, Environmental Rasters for Ecological Modelling, Environmental Niche Modelling Tool, Maxent, R + RStudio, Zotero, and WorldClim. We appreciate the review provided by the Associate Editor, Dr. Mike Clearwater, and two referees. Abraão Almeida Santos would like to thank the Brazilian Council for Research (CNPq) for the postdoctoral grant (number 151765/2020). The authors acknowledge the support from the Cooperative Research Centre for Honey Bee Products, Spring Gully Foods, and the Waite Research Institute.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The ‘Conselho Nacional de Desenvolvimento Científico e Tecnológico’ supported this study [grant number 142410/2017-9]; the Australian Government’s Cooperative Research Centres Program; and Cooperative Research Centre for Honey Bee Products.