Video | Business Headlines | Internet | Science | Scientific Ethics | Technology | Search


Introduced insects not such a pest

Introduced insects not such a pest

Lincoln, New Zealand 14 January 2014... Concerns are often raised about the introduction of non-native insects around the world to control weeds, citing the risk the introduced insects may cause to other desirable plant species. Yet a new study suggests there may not be as much evidence for this concern as people perceive.

An international collaboration - including Max Suckling of Plant & Food Research in Lincoln, New Zealand and René Sforza of the European Biological Control Laboratory in Montpellier, France - has completed a study on the effects of all recorded cases since the 1800s of insects as weed biological control agents thanks to funding from an OECD Fellowship and as part of NZ’s Government funded Better Border Biosecurity programme ( ).

The research characterised the magnitude of unwanted effects by these insects on other plants using a five step scale adapted from invasive species biology and looked at 512 cases of deliberately introduced biocontrols dating back more than 150 years.

Dr Suckling said “A total of 43 weed biocontrol insects worldwide have been reported to feed on non-target plants after release, but the real surprise comes when you look at the level of this feeding and what little effect it is having on the plants, compared with calls for concern about biosafety in the scientific literature”.

The study particularly looked at whether insect feeding affected the reproductive rate of the non-target plant and discovered decreases in plant reproduction in non-target plants to be very rare.
The scientists found only four insects causing plant populations to decline significantly anywhere.

“Weeds are a major long term drain to our quality of life. Our concern is that worry about biosafety needs to be tempered with the benefit scenario. Our analysis shows that as far as is known, weed biological control agents have historical had an excellent biosafety track record, with more than 99% of cases avoiding significant non-target impacts on plant populations” says Dr Suckling.

“Biological control of weeds through the introduction of specific insects is an environmentally sustainable solution compared to chemical sprays and an area of science we aim to investigate further” notes Dr Sforza, currently visiting New Zealand on an OECD Fellowship for biological control.

The study estimates that in the nearly 85 year history of weed biological control in New Zealand, 34 % of insects deliberately introduced against weeds have worked successfully, in some cases with real benefits. Two key success stories have occurred from insects introduced to control St John’s Wort and Ragwort, with long-term ecosystem recovery over large areas.

The study notes that in future it is expected that even fewer non-target impacts and greater benefits can be expected due to improved science and increased incorporation of wider societal values and that suitably-screened organisms can be released with a very high degree of specificity against weeds. The research paper is available online in PLoS ONE (10.1371/journal.pone.0084847).

View the research paper online
PLoS ONE – article by Suckling and Sforza,
What magnitude are observed non-target impacts from weed biocontrol? (
10.1371/journal.pone.0084847 (


© Scoop Media

Business Headlines | Sci-Tech Headlines


DIY: Kiwi Ingenuity And Masking Tape Saves Chick

Kiwi ingenuity and masking tape has saved a Kiwi chick after its egg was badly damaged endangering the chick's life. The egg was delivered to Kiwi Encounter at Rainbow Springs in Rotorua 14 days ago by a DOC worker with a large hole in its shell and against all odds has just successfully hatched. More>>


Trade: Key To Lead Mission To India; ASEAN FTA Review Announced

Prime Minister John Key will lead a trade delegation to India next week, saying the pursuit of a free trade agreement with the protectionist giant is "the primary reason we're going" but playing down the likelihood of early progress. More>>



MYOB: Digital Signatures Go Live

From today, Inland Revenue will begin accepting “digital signatures”, saving businesses and their accountants a huge amount of administration time and further reducing the need for pen and paper in the workplace. More>>

Oil Searches: Norway's Statoil Quits Reinga Basin

Statoil, the Norwegian state-owned oil company, has given up oil and gas exploration in Northland's Reinga Basin, saying the probably of a find was 'too low'. More>>


Modern Living: Auckland Development Blowouts Reminiscent Of Run Up To GFC

The collapse of property developments in Auckland is "almost groundhog day" to the run-up of the global financial crisis in 2007/2008 as banks refuse to fund projects due to blowouts in construction and labour costs, says John Kensington, the author of KPMG's Financial Institutions Performance Survey. More>>


Health: New Zealand's First ‘No Sugary Drinks’ Logo Unveiled

New Zealand’s first “no sugary drinks logo” has been unveiled at an event in Wellington... It will empower communities around New Zealand to lift their health and wellbeing and send a clear message about the damage caused by too much sugar in our diets. More>>


Get More From Scoop

Search Scoop  
Powered by Vodafone
NZ independent news