Biocontrol introduction

Target pest: Araujia hortorum (Gentianales: Apocynaceae) = Araujia sericifera, moth plant

Agent introduced: Puccinia araujiae (Pucciniales: Pucciniaceae), moth plant rust

Import notes:

Landcare Research (2016) - approved for release in 2015 but no releases made as yet as waiting for export permit to be granted by the Argentinian authorities.

Landcare Research (2017g) - still waiting for export permit.

Landcare Research (2019g) - still no permit to export from Argentina. The rust could be potentially be sourced from Uruguay but this is not straightforward. In the native range the rust is attacked by a hyperparasitic fungus (Cladosporium uredinicola) and is not easy to find. An Argentinian collaborator has retained a culture of the rust that is free of the hyperparasite, achieved after much painstaking effort. If the rust could be collected in Uruguay it would be a massive undertaking to repeat all this work, let alone the host-range testing, but this option will be explored with the project funders in the near future.

Impacts on non-targets:

Anderson et al. (2016) - moth plant belongs to the family Apocynaceae, subfamily Asclepiadoideae, tribe Asclepiadeae, subtribe Oxypetalinae. Host specificity testing was carried out on members (all present in New Zealand) of three subfamilies and six tribes in the family Apocynaceae. Puccinia araujiae caused disease only to species in the same subtribe (Oxypetalinae) as moth plant. These results are consistent with the host range of the fungus reported in the literature and in previous experimental results. There are no members of the Oxypetalinae native to New Zealand. The only indigenous taxa in the Apocynaceae are three species of Parsonia, which belong to a different subfamily from moth plant. Five individuals of one species of Parsonia were tested and all were immune.

EPA Applications:

EPA (2015c) - 17 Aug 2015: application by the Northland Regional Council to import and release the moth plant rust fungus, Puccinia araujiae, as a biocontrol agent for the weed moth plant, Araujia hortorum. EPA application # APP202529, approved without controls 15 Dec 2015.

References

Anderson FE, Santos López SP, Sánchez RM, Reinoso Fuentealba CG, Barton J (2016). Puccinia araujiae, a promising classical biocontrol agent for moth plant in New Zealand: Biology, host range and hyperparasitism by Cladosporium uredinicola. Biological Control 95: 23-30 https://doi.org/10.1016/j.biocontrol.2015.12.015

EPA (2015c). EPA application APP202529 to import and release the moth plant rust fungus, Puccinia araujiae as a biocontrol agent for the weed moth plant. Environmental Protection Authority website https://www.epa.govt.nz/database-search/hsno-application-register/view/APP202529

Landcare Research (2016i). Who's who in biological control of weeds? Weed Biocontrol: What's New? 77: 10-11 http://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-77

Landcare Research (2017g). Who's who in biological control of weeds? Weed Biocontrol: What's New? 81: 10-11 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/issue-81

Landcare Research (2019g). Moth plant beetle misconception cleared up. Weed Biocontrol: What's New? 89, August 2019 https://www.landcareresearch.co.nz/publications/newsletters/biological-control-of-weeds/weed-biocontrol-issue-89/moth-plant-beetle-misconception-cleared-up