Update on releases of Selitrichodes neseri, biocontrol agent for Leptocybe invasa
Releases of Selitrichodes neseri in Eucalyptus plantations in South
Africa continue, with over 4 000 female wasps released at over 200 sites
to date. These releases have focused on the regions with the highest
infestation of Leptocybe invasa, namely Zululand, the Lowveld and
Tzaneen, although releases have also been done in other areas such as
KZN Midlands and Piet Retief-Paulpietersburg.
Release sites in each region are being monitored to investigate the
establishment of S. neseri. Encouragingly, S. neseri has been recovered
from all but one of these sites. Currently, the primary goal is to
distribute S. neseri as widely as possible in the infested areas, with
the expectation that the releases will develop in to source populations
of S. neseri that will grow and spread naturally. The rate of
establishment of S. neseri and the impact that its establishment will
have on L. invasa populations is not yet known, and we will need to
monitor selected release sites carefully to better understand this.
Attached is a map from the ICFR (Ryan Nadel and Ilaria Germishuizen)
that shows the distribution of releases. Please note that the map does
not include all releases, as release site information is still being
collected from various sites, especially in the Zululand region.
The release of S. neseri is a huge effort that requires the
participation of farmers, foresters, managers, researchers and others.
Thank you to the numerous people involved in the releases of S. neseri
and to the team at the FABI Biocontrol Centre for the rearing of these
Brett Hurley (PhD)
Researcher and Senior Lecturer
Department of Zoology and Entomology
Tree Protection Cooperative Programme (TPCP)
Forestry and Agricultural Biotechnology Institute (FABI)
University of Pretoria