jenner_and_kuhlmann.fm Seite 102 Mittwoch, 3. März 2010 3:29 15 JOURNAL FÜR KULTURPFLANZEN, 62 (3). S. 102–106, 2010, ISSN 0027-7479 VERLAG EUGEN ULMER KG, STUTTGART Themenheft Wade Harley Jenner, Ulrich Kuhlmann Refining the implementation of arthropod classical biological control Klassische biologische Schädlingsbekämpfung: Erfahrungen und neue Entwicklungen für die Praxis 102 Abstract Zusammenfassung The last few decades have been turbulent for the reputa- In den letzten zwei Jahrzehnten ist die Anwendung von tion and practice of arthropod classical biological con- klassischer biologischer Schädlingsbekämpfung in Verruf trol. Public and scientific support for this pest manage- geraten. Zurzeit erfährt dieser Ansatz allerdings wieder ment approach has risen, fallen and appears to be rising wachsenden Zuspruch. Durch Berichte über negative again. Due to reports in the 1980s and 1990s of negative Auswirkungen von Nützlingen, eingesetzt in der klassi- environmental effects caused by classical biological schen biologischen Schädlingsbekämpfung, auf ihre Um- control agents, practitioners have scrambled to develop welt, waren Wissenschaftler gezwungen, neue Verfahren better risk assessment measures. Since the mid-1990s, zu entwickeln, um eventuelle Risiken besser abschätzen several national and international guidelines have been zu können. Seit Mitte der neunziger Jahre wurden daher created that assign responsibilities to the players in- zahlreiche nationale und internationale Richtlinien ent- volved in selection and release of exotic beneficial wickelt, um den an der Auswahl und Freilassung von exo- insects. At the same time and on a more technical level, tischen Nützlingen beteiligten Personen die jeweiligen researchers have been working to develop standardised Pflichten aufzuzeigen. Zur gleichen Zeit begannen Wis- procedures for the risk assessment of proposed classical senschaftler praxisnahe, standardisierte Verfahren zur biological control agents. The lack of well-established Risikoabschätzung von Nützlingen zu entwickeln. Der protocols (like those that exist for weed biological con- Mangel an im praktischen Einsatz erprobten Verfahren, trol) has been a great impediment to the implementation wie sie zum Beispiel für die klassische biologische of meaningful risk assessments. Along with other Bekämpfung von Unkräutern bereits existieren, stellt research groups, the biological control scientists at CABI nach wie vor ein großes Hindernis für eine sinnvolle Europe-Switzerland are using current projects to tackle Risikoabschätzung von Nutzarthropoden dar. In Zusam- problems associated with estimating agent host speci- menarbeit mit anderen Forschungsgruppen nutzen die ficity and risk assessment. In particular, the arthropod Mitarbeiter von CABI Europe-Switzerland laufende For- classical biological control team is working on key host schungsprojekte, um Probleme bei der Abschätzung der range testing issues including methods for selection of Wirtsspezifität von Nützlingen und den damit verbunde- non-target species, design and implementation of host nen Risiken zu lösen. Besonders die Arbeitsgruppe zur specificity experiments, and extrapolation of laboratory klassischen biologischen Bekämpfung von Arthropoden results to a field context. richtet ihr Hauptaugenmerk auf die Entwicklung von Laborverfahren zur Abschätzung der Wirtsspezifität von Key words: Host range, risk assessment, leek moth, agent Nützlingen und deren Aussagekraft im Vergleich mit selection Freilanduntersuchungen. Institution CABI Europe-Switzerland, Delémont, Switzerland Correspondence Dr. Wade Harley Jenner, Dr. Ulrich Kuhlmann, CABI Europe-Switzerland, Rue des Grillons 1, 2800 Delémont, Switzerland, E-Mail: [email protected] Accepted February 2010 jenner_and_kuhlmann.fm Seite 103 Mittwoch, 3. März 2010 3:29 15 W.H. JENNER and U. KUHLMANN, Refining the implementation of arthropod classical biological control Stichwörter: Wirtsspezifität, Risikoabschätzung, Lauch- No. 3). This guideline helped to clarify the responsibilities motte, Auswahl eines Nutzarthropoden of parties involved in the shipping, receiving and releas- Themenheft ing of biological control agents. However, like similar documents that were produced at the time, it indicated Arthropod Classical Biological Control under Fire what information was required, but did not specify effec- tive methodologies to obtain that information. For Classical biological control is a process in which exotic instance, there were no explanations available on how to natural enemies are introduced to control invasive alien select agents in a responsible and standardised way. This pests. It is often more feasible, more efficient and less lack of robust methodologies to minimise risks associated environmentally damaging than alternative strategies, with agent introductions has become one of the biggest such as the use of pesticides or large-scale habitat manip- topics in arthropod classical biological control. Some of ulation. Classical biological control works on the philos- the key issues for which protocols are currently being ophy that the high density of many invasive species is developed include: (1) selecting non-targets for testing, caused by their separation from the natural enemies that (2) running host specificity experiments, (3) interpreting controlled them in their native ranges. Therefore, in most laboratory results and extrapolate them to field situa- cases, the beneficial agents come from the area of origin tions and (4) conducting risk-benefit analyses. of the pest and have an evolutionary association with the pest. This pest management approach typically targets weed and arthropod pests, but has even been used Restoring Arthropod Classical Biological Control as a 103 against vertebrates and molluscs. This paper, however, Green Alternative will deal solely with classical biological control of arthro- pods. With its long history of involvement in weed and arthro- Since the historic first releases of the vedalia beetle pod classical biological control, CABI has continuously (Rodolia cardinalis) against cottony cushion scale (Icerya employed practitioners over the turbulent decades which purchase) in Californian citrus orchards in 1888, this saw the rise, fall and recent renewal of public faith in method of arthropod pest management has had wide- biological control. In particular, researchers at CABI spread use. Over the last 120 years, more than 2000 spe- Europe-Switzerland have had first-hand experience with cies of entomophagous agents have been used in classical these issues and are currently working to develop needed biological control. Against the backdrop of severe envi- methodologies for the selection of safe and effective ronmental and human poisoning from synthetic insecti- agents. One of the most significant and recent contribu- cides in the 1960s and 1970s, biological control was tions, in close collaboration with Agroscope, FAL Recken- considered an environmentally friendly and “green” holz, Switzerland, has been the production of a book technology. Because there was no evidence of negative discussing methodologies for risk assessment (BIGLER et effects on wildlife, little thought was given to risk assess- al., 2006). This book, written by a large team of interna- ment or risk mitigation. tionally recognised biological control experts, describes However, the scientific and public image of biological emerging methods for things such as determination of control began to change in the 1980 s with the publica- agent specificity, molecular-based species identification tion of reports indicating that certain introduced agents and evaluation of post-release establishment, dispersal were having negative impacts on native non-target spe- and impact. cies (HOWARTH, 1983, 1991). In retrospect, it is interest- Along with other research institutions in Europe, CABI ing that this should have come as a surprise, given that has also been engaged in shaping European policy on the the potential for non-target impacts had long been recog- regulation of exotic agents. Europe lags far behind nised in weed biological control. Phytophagous classical Australia, New Zealand and North America in terms of biological control agents were already regularly under- implementing regulatory procedures for the import and going risk assessments that were intended to minimise release of classical biological control agents. For exam- non-target effects. The key difference was that native and ple, by 2000, very few European countries were regulat- economically important plants were highly valued ing the release of beneficial arthropods. It has therefore whereas people were less sympathetic towards poorly been the Europe Union’s priority to formulate a regula- understood non-target arthropods. It was primarily due tory system that will be readily approved of and adopted to a growing interest in biodiversity that people became by all member countries. Through an EU-funded policy more concerned about non-target arthropods. support action called ‘Regulation of Biological Control The growing criticisms of classical biological control Agents’ (REBECA), two reports were compiled compar- led practitioners to re-evaluate their agent selection ing regulatory frameworks among European countries process. By the mid-1990s, national and international (LOOMANS, 2007) and those in Australia, New Zealand, policies began to be developed and adopted by numerous Canada and the USA (HUNT et al., 2008). This project countries in an attempt to ensure responsible