Supplemental host range of Araujia mosaic virus, a potential biological control agent of moth plant in New Zealand

Araujia mosaic virus (ArjMV) has previously been confirmed to have a narrow host range and is considered a potential biological control agent for moth plant (Araujia hortorum), a troublesome environmental weed in northern regions of New Zealand. In this study, the virus was tested on 14 plant species, including species of importance to New Zealand to explore its possible use as a biocontrol agent for moth plant. Mosaic symptoms and occasional distortion were observed on leaves of the three Araujia species tested. Mosaic symptoms were seen on Morrenia odorata and Oxypetalum caeruleum, while mosaic symptoms, chlorotic spots and leaf distortion were observed on all three of the Gomphocarpus species tested. No symptoms were observed on Asclepias curassavica, Catharanthus roseus, Hoya carnosa, Mandevilla × amabilis, Nerium oleander and Vinca major. Because ArjMV infected the three Araujia species causing stunting, this virus would significantly reduce flowering and seed production in these species. The monarch butterfly (Danaus plexippus) relies on Gomphocarpus fruticosus for successful development and is highly valued in New Zealand. It may be possible to genetically modify ArjMV to prevent transmission by insects but it is not an option because genetically modified organisms are not widely supported by the New Zealand public. The research efforts are now focusing on other potential agents for biocontrol of moth plant in New Zealand.