Assessing the population dynamics of invasive ragweed to predict outcomes of biological control and other management interventions

• Forschungsstelle: COST
• Projektnummer: C13.0146
• Projekttitel Englisch: Assessing the population dynamics of invasive ragweed to predict outcomes of biological control and other management interventions

Schlüsselwörter (Englisch)

Alien invasive plant species; classical biological control; plant-herbivore interactions; plant demography; plant population models

Forschungsprogramme (Englisch)

COST-Action FA1203 - Sustainable management of Ambrosia artemisiifolia in Europe (SMARTER)

Kurzbeschreibung (Englisch)

The North American common ragweed, Ambrosia artemisiifolia L. (Asteraceae), has become an invasive alien plant in several continents, including Europe. Classical biological control has been proven to be an environmentally friendly and cost-effective method to achieve long-term control of invasive plants. Whereas this method has been successfully implemented against ragweed on other continents, it is not yet implemented in Europe. The development of classical biological control is one of the main aims of the COST Action “SMARTER”. Here, we propose a theoretical and experimental approach using population dynamic models to predict the efficacy of different candidate biological control agents of ragweed, and to provide a scientific basis for the future evaluation of applied biological control. Specifically we will (i) initiate and manage a database on ragweed demography across the introduced range, (ii) develop a widely-applicable plant population dynamics model for ragweed and (iii) extend this model to predict the effect of different biological control agents (including timing and damage level). This innovative tool will help to compare management options prospectively as well as retrospectively, which in turn will significantly contribute to develop region- and habitat-specific best practice manuals for the integrated management of ragweed, one of the main deliverables of COST-SMARTER, and advance the science underlying target impact studies for biological control.

Partner und Internationale Organisationen (Englisch)

AT; BE; BA; HR; CZ; DK; EE; FI; FR; F,Y.R. of Macedonia; DE; EL; HU; IL; IT; LT; LU; NL: PL; RO; RS; SK; SI; ES; SE; TR; UK; RU; AM; CN

Abstract (Englisch)

The project 5 progressing weil. With respect to Task A and B, the data base on ragweed demography is steadily growing. The large amount of data, including those collected by others, has involved more time on data managementthan expected, and has delayed publication ofthe data and development ofthe demographic modei. The two publications that were planned for the second year (the theoretical modei, and environmental drivers of reproduction) are now in progress. In the next year, the last data will be collected and the main publication on a general demographic model for Ambrosia using data from 3 years of monitoring will be wriften. The data of the first two years indicate high year-to-year variation, which will be a challenge to model accurately. With respect to Task C, we pursued our focus on Ophraella communa. Experimental work revealed that the impact ofthis beetle is highly variable and context-dependent. In the next year, we will extend the experiments on more sites and with more details on beetle densities. We will integrate the resuits into the demographic model to projectthe long-term impact ofthe beetle on ragweed population growth. In collaboration with other SMARTER members, we conducted additional experimental/modelling studies and found i) that the potential distribution of 0. communa and 5 other candidate agents in Europe is insufficient to cover the ragweed-infested area; ii) that 0. communa performs bettet under European conditions than its congener 0. slobodkini that was originally prioritized for ragweed biocontrol, but is less safe for the most hazardous non-target plant; iii) no impact of 0. communa on ragweed pollen quality and allergenicity under laboratory conditions; and these resuits have resulted in three joint papers (all under review). Finally, with respect to advancing weed biocontrol in Europe, we organised jointly with EPPO and IOBC a 2nd workshop on European regulation of biocontrol agents, which needs harmonisation to support releases for weed control in practice.

Datenbankreferenzen (Englisch)

Swiss Database: COST-DB of the State Secretariat for Education and Research Hallwylstrasse 4 CH-3003 Berne, Switzerland Tel. [phone] Swiss Project-Number: C13.0146