Potential invasion of Spodoptera frugiperda in Switzerland and options for sustainable control methods.

• Forschungsstelle: BLW
• Projektnummer: 19.17

Schlüsselwörter (Deutsch)

Biologische Kontrolle, Invasive Arten, Integrierter Schädlingungsbekämpfung, Spodoptera frugiperda

Schlüsselwörter (Englisch)

Biological control, Invasive species, IPM, Spodoptera frugiperda

Schlüsselwörter (Französisch)

lutte biologique, espèces envahissantes, lutte intégrée contre les ravageurs, Spodoptera frugiperda

Schlüsselwörter (Italienisch)

Controllo biologico, Specie invasive, Gestione integrata dei parassiti, Spodoptera frugiperda

Kurzbeschreibung (Englisch)

The moth Spodoptera frugiperda is a pest of maize and other cereals, native from the Americas. It has recently invaded the sub-Saharan Africa, is now also found in several South Asian countries and is likely to invade North Africa and southern Europe in the near future. It is not able to survive low winter temperatures, however, it is able to migrate thousands of km every summer and cause damage in temperate regions. Present climate models suggest that, under present and near-future climate, S. frugiperda cannot establish permanently into Central Europe, but migratory populations are likely to invade regularly, if the moth is able to establish permanent populations around the Mediterranean Sea. The proposed project aims at answering the following questions:
1: What is the risk that S. frugiperda establishes in or regularly migrates to CH in a near future?
2: Which sustainable control methods are potentially suitable for Switzerland?
The project will be conducted in close collaboration with two international projects (Euphresco and “Action on Invasives”) taking into account the specificities of Switzerland such as the availability of biological control agents and the ban on GM crops.

Kurzbeschreibung (Französisch)

La mite Spodoptera frugiperda est un ravageur qui s’en prend au maïs et à d’autres sortes de céréales et est originaire du continent américain. Elle a récemment pénétré en Afrique subsaharienne et est entre-temps aussi présente dans plusieurs pays d’Asie du Sud-Est. Dans un proche avenir, elle pénétrera vraisemblablement en Afrique du Nord et en Europe du Sud. Il existe par conséquent un risque que ce ravageur s’en prenne aussi à des cultures suisses au cours de l’été. On examinera pour cette raison, dans le cadre de ce projet, quel est le risque que cette mite apparaisse durablement ou à intervalles réguliers également en Suisse et quelles méthodes pourraient être utilisées en Suisse pour la combattre.

Abstract (Englisch)

This project aimed at assessing the risk that the invasive fall armyworm, Spodoptera frugiperda, establishes or regularly migrates to Switzerland in a foreseeable future and, at reviewing and testing sustainable management methods that would be available in Switzerland. The parameters of two climate models were applied to Europe and showed that the pest will permanently establish only in areas in the Mediterranean region experiencing the warmest winter temperatures. However, migratory waves should be expected in many European countries, including Switzerland. The limiting factors of these waves will be the size of populations developing in spring around the Mediterranean Sea, and the direction and strength of the winds.  A review of management methods suitable for Switzerland and Europe is presented, with a list of recommendations for sustainable and IPM-compatible methods. A specific literature survey focused on studies of augmentative biological control agents that are available in Europe, or closely related species that are supposed to react identically. Finally, three species of natural enemies that have not yet been assessed elsewhere against S. frugiperda and are readily available in Switzerland, the egg parasitoids Trichogramma brassicae and T. dendrolimi and the ladybird Adalia bipunctata, were tested in laboratory assays. These showed that A. bipunctata is not an efficient predator of S. frugiperda eggs and larvae. Trichogramma spp. showed more potential, but they mainly parasitize well-exposed eggs and cannot easily reach those covered by scales or hidden by other eggs.