Prospects for biological control of Lonicera japonica (Caprifoliaceae) in New Zealand

Abstract

Surveys in the native range of Japanese honeysuckle Lonicera japonica in Honshu, Japan, revealed a natural enemy biota attacking the plant that was rich in potential biocontrol agents for New Zealand (NZ), including 11 herbivorous insect species and one fungal pathogen. This contrasts with previously published surveys in NZ that found only generalist arthropod herbivores and only two weakly pathogenic specialist pathogens. The Japanese insect herbivores included leaf-mining and stem-boring feeding guilds that were absent in NZ. Among the insect herbivores, a nymphalid butterfly Limenitis glorifica, a cerambycid beetle Oberea shirahatai and a cosmopterigid moth Allotalanta sp. were prioritised as potential biocontrol agents. Their larvae cause potentially complementary damage to leaves, woody stems and shoot tips, respectively. Host-range testing of Lim. glorifica and O. shirahatai indicated that both species are sufficiently host-specific to be released in NZ and formal approval to release these species has been obtained. Lim. glorifica was released into the field in 2014 and has become established. O. shirahatai is due to be released in late 2016. Preliminary testing indicates that the fundamental host range for Allotalanta sp. larval feeding and development is narrowly oligophagous. Allotalanta sp. is therefore likely to have potential for use as a biocontrol agent in NZ if the first two agents provide insufficient control, although further host-range testing would be desirable to more accurately predict the likely field host range of this species.