CABI News

biocontrols

CABI scientists have joined an international team of researchers as part of a Special Issue of the journal Current Opinion in Insect Science which focuses on the present status and potential future directions of weed biological control using arthropods.

Dr Urs Schaffner from CABI’s centre in Switzerland and Prof. Heinz Müller-Schärer (University of Fribourg, Switzerland) edited the special issue. Dr Hariet Hinz, Dr Arne Witt, who is based at CABI’s centre in Kenya, and Dr Schaffner are all either lead or co-authors on individual papers.

In the Editorial overview, Prof Müller-Schärer and Dr Schaffner emphasize that historically a close partnership between basic research and weed biological control contributed to the development of guidelines for pre-release assessment of non-target risks in weed biological control. They argue that, with the availability of new technologies and the increased incorporation of evolutionary processes, tight links between practitioners and academia will become ever more important in the future to make weed biological control even more efficient, predictable, sustainable and safe.

Dr Hinz is lead author on the paper ‘A global review of target impact and direct nontarget effects of classical weed biological control’ which recognises that recent reviews show classical weed biocontrol measures can be successful in reducing the negative impacts of invasive plant species, have impressive returns on investment, and contribute to slower rates of weed spread.

Dr Hinz and co-authors Dr Rachel Winston and Dr Mark Schwarzländer go on to suggest that quantitative post-release monitoring is necessary to account for differences in biocontrol outcomes across spatial and temporal scales.

They also argue that direct nontarget attack (NTA) incidence and severity are decreasing over time, and pre-release host-specificity tests can accurately predict NTA post-release, as long as the nontarget plant species are included in testing.

The scientists demonstrate less than 1% of NTA was found where the impacted plant species had been tested pre-release and was deemed not at risk. In conclusion, they believe that effectiveness and environmental safety will likely further improve with the incorporation of new technologies, such as experimental evolutionary studies.

Meanwhile, Dr Schaffner is lead author on another paper ‘Post-release monitoring in classical biological control of weeds: assessing impact and testing pre-release hypotheses’ that reviews recent advances in understanding the demography of biological control agents released into a novel environment and the consequences for the resident plant and animal communities and ecosystem functioning, including the restoration of ecosystem services.

Dr Schaffner and co-authors Dr Martin Hill, Dr Tom Dudley and Dr Carla D’Antonio argue that post-release monitoring of classical biological control of weed (CBC) programs offers unique but largely underutilized opportunities to improve our understanding of CBC outcomes and to inform management and decision-makers on when and how CBC should be integrated with other management options to enhance ecosystem restoration.

Finally, Dr Schaffner and Dr Witt are co-authors on two other papers. Dr Schaffner contributed to the paper ‘Quantifying the social and economic benefits of the biological control of invasive alien plants in natural ecosystems’ while Dr Witt shared his expertise on the paper ‘Weed biological control in low- and middle-income countries’.

Dr Schaffner, Head Ecosystem Management, said, “Invasive plants can pose serious threats to native species, ecosystems, human health and many sectors of the economy such as agriculture, forestry and tourism.

“CABI’s contribution to the special issue in ‘Current Opinion in Insect Science’ draws together the very latest expertise in the field of classical biological control of weeds using arthropods as environmentally friendly and cost-effective means of managing invasive weeds. Biological control is the only management method for invasive plants with a chance for sustainable, long-term control, especially in extensively managed or environmentally sensitive areas.

“Furthermore, our part in this special issue is an extension of our work in simultaneously researching and developing insect, mite and fungal control agents that can also help farmers protect and enhance their livelihoods.”

 

Additional information

Photo: Researching the management of common pest pear Opuntia stricta in the UNESCO World Heritage site Socotra Archipelago, Yemen.

 

Full paper references

Müller-Schärer, H., Schaffner, U., ‘Editorial overview: Biological control of plant invaders: a continued stimulus and yet untapped potential to link and advance applied and basic research’, April 2020, Current Opinion in Insect Science, DOI: 10.1016/j.cois.2020.03.002

Hinz, L. H., Winston, L. R and Schwarzländer, M., ‘A global review of target impact and direct nontarget effects of classical weed biological control’, April 2020, Current Opinion in Insect Science, DOI: 10.1016/j.cois.2019.11.006

Schaffner, U., Hill, M., Dudley, T and D’Antonio, C., ‘Post-release monitoring in classical biological control of weeds: assessing impact and testing pre-release hypotheses’, April 2020, Current Opinion in Insect Science, DOI: 10.1016/j.cois.2020.02.008

Van Wilgen, W. B., Raghu, S., Sheppard, W. A. and Schaffner, U., ‘Quantifying the social and economic benefits of the biological control of invasive alien plants in natural ecosystems’, April 2020, Current Opinion in Insect Science, DOI: 10.1016/j.cois.2019.12.004

Day, M., Witt, A. and Winston, R., ‘Weed biological control in low- and middle-income countries’, April 2020, Current Opinion in Insect Science, DOI: 10.1016/j.cois.2020.02.004

Link to the complete series of papers in the special issue with an Editorial and nine contributed papers:

https://www.sciencedirect.com/journal/current-opinion-in-insect-science/vol/38/

 

Biological control of invasive plants

CABI has over 60 years’ experience of working on the biological control of invasive weeds. Find out more here: https://www.cabi.org/what-we-do/cabi-centres/biological-control-of-invasive-plants/