CABI-led review highlights potential management options for fall armyworm pest in Europe

Date:12-20-2022

CABI scientists have published a review of potential management options farmers in Europe could take against an expected invasion of the fall armyworm pest which has already devastated maize crops in Africa and other parts of the world.

The researchers from CABI’s centre in Switzerland suggest a forecasting system – at a regional and local level – should be established to alert growers of the likely seasonal arrival of the pest so that action can be taken to minimize loss of yields.

As outlined in the Journal of Economic Entomology, the review states that recent climatic models reveal that the fall armyworm (Spodoptera frugiperda) is likely to establish itself in the southern parts of Europe including southern Spain, Italy, Portugal or Greece.

Already, in 12 of Africa’s maize-producing countries, the fall armyworm has the potential to cause yield losses in a range from 8.3 to 20.6m tonnes per year in the absence of any control methods. The value of these losses is estimated to be between £2.4bn and £6.2bn.

Lead author Dr Dirk Babendreier and colleagues Dr Stefan Toepfer, Dr Melanie Bateman and Dr Marc Kenis believe that the pest is best managed sustainably – without an over reliance on more harmful to the environment chemical pesticides – by way of using biological pest control products or through conservation biological control.

This includes, they say, the stimulation of natural enemies through the planting of flower strips or intermediate cover crops, reducing tillage intensity, and avoiding broad-spectrum insecticides.

To manage fall armyworm infestations, the scientists suggest that there are several effective biologically-based products which are available globally – and some in Europe – based on specific baculoviruses, certain Bacillus thuringiensis strains, few entomopathogenic nematodes, and a number of botanicals.

Fall armyworm damage on maize crop (Credit: CABI).

The parasitoid Telenomus remus, for example, would be able to parasitize the eggs of the fall armyworm and kill them. However, further research is needed to determine optimal release rates, release times and frequencies, number of release points, the best stage and device for releases and other aspects such as how large the fields should be to achieve efficient pest control.

Dr Babendreier said, ″Whilst a number of cultural control methods are adopted by maize growers in different regions globally to fight fall armyworm, many of them may either not be highly effective, too laborious, or otherwise unfeasible within the mechanized crop production systems used in Europe.″

″Plant protection companies, particularly biocontrol companies should act proactively in starting registration of ingredients and products against fall armyworm in Europe. European maize growers should be made aware, in time, of key features of this new invasive pest and appropriate control options.″

One way on which biological control agents can be promoted to use against the fall armyworm in Europe is through the CABI BioProtection Portal. This is a free tool to enhance the awareness and uptake of biocontrol and biopesticide products which have less impact on ecosystems including soils, rivers, lakes and wildlife.

″Registration authorities may allow emergency registrations of plant protection products in case of a sudden arrival of fall armyworm,″ Dr Babendreier added. ″However, we advise that such emergency registration concentrates on biological options already existing for the control of this pest.″

Full paper reference

Dirk Babendreier, Stefan Toepfer, Melanie Bateman, Marc Kenis, Potential Management Options for the Invasive Moth Spodoptera frugiperda in Europe, Journal of Economic Entomology, Volume 115, Issue 6, December 2022, Pages 1772–1782, https://doi.org/10.1093/jee/toac08

You can read the full paper open access here: https://academic.oup.com/jee/article/115/6/1772/6895755