IPSolut

Project

Researching the basics for the development of an inundative biological control procedure for the eight toothed spruce bark beetle (Ips typographus L.) – IPSolut

Project period

08/2021 - 10/2024

Supporting collaborator

Staatsbetrieb Sachsenforst

Project description

Climate change and the increasing frequency of storms, droughts and heat waves pose more and more challenges to forests and foresters. Particularly Norway spruce (Picea abies L.) is currently in focus due to its high share of forest area and the severe threat by the eight toothed spruce beetle (Ips typgraphus L.) and other bark beetle species. The compatibility of economic, ecological and social demands on forests require innovative and sustainable approaches, since the current procedure of a 'clean forest management' reaches its limits. Providing close-to-nature regulation methods is a necessary addition to current regulation methods, such as the application of non-selective insecticides or the debarking of timber.

This is the starting point of IPSolut, whose research aims at effectively controlling the population density of I. typographus on a local level by releasing mass bred parasitoid hymenopterans, that is, by inundative biologcal control. The goal is to achieve a parasitization rate of the developmental stages of I. typographus that is high enough to result in population size drop below a critical threshold value. This goal is reached if the remaining bark beetle population is no longer able to cause new infestations on standing trees.

Within the project the basics and principles for the development of a mass breeding and release procedure are to be established. Research will focus on questions such as which parasitoid species from the Hymenoptera order has or have the greatest potential to control I. typographus and as the most favorable preconditions for a successful mass breeding. This includes the identification of naturally occuring parasitoids as well as the establishment and maintenance of breedings of I. typographus, selected target species and alternative host species. Furthermore, biological-ecological aspects, e. g. the temperature tolerance of hymenopterans or the accompanying vegetation in Norway spruce stands, have to be considered, since they play an important role in the successful establishment of released parasitoids. It could be possible to develop management measures that promote the persistence of released parasitoids in the ecosystem and simultaneously increase the occurrence of other antagonist species and hence the overall biological diversity.

The release of parasitoids to control I. typographus is supposed to take place on wood piles, on sites of ongoing infestations within forests or in the peripheral areas of large protected areas, for example, to prevent a spillover of existing bark beetle populations to commercially used forest areas. While I. typographus serves as an exemplary species within the project, the findings and principles can most likely be transferred directly or indirectly to other pest organisms, such as different bark beetle species and important pest species of Scots pine and oak.

Project related publications, presentations and theses

Lawall A., Spann E. (2022): Entlarvt! Mit parasitoiden Schlupfwespen gegen den Buchdrucker Ips typographus L. - Aktuelles aus den Projekten EIVES und IPSolut. Vortrag zum 21. Treffen des Arbeitskreises Vorratsschutz der Deutschen Phytomedizinischen Gesellschaft e. V. vom 29. bis 30. März 2022 in Tharandt.
Lawall A., Spann E. (2022): Entlarvt! Mit parasitoiden Schlupfwespen gegen den Buchdrucker Ips typographus L. - Aktuelles aus den Projekten EIVES und IPSolut. Vortrag zur entomo.ch 2022, der Jahrestagung der Schweizerischen Entomologischen Gesellschaft vom 20. bis zum 21. Mai 2022 in Lugano, Schweiz.
Lawall A. (2023): IPSolut – Erforschung von Grundlagen für die Entwicklung eines Verfahrens zur inundativen biologischen Bekämpfung des Buchdruckers (Ips typographus L.)". Vortrag zur DGaaE Entomologentagung 2023 vom 20.-23. Februar 2023 in Bozen, Italien.