Ground beetles could have a key role in controlling weeds in cereal crops, according to new research.

Researchers funded by the Biotechnology and Biological Sciences Research Council and the Institut National de la Recherche Agronomique (INRA) have for the first time shown that ground beetles can reduce the amount of weed seeds in the soil seedbank.

They believe these findings suggest the need to conserve farmland biodiversity. David Bohan of Rothamsted Research, who led the research, said: “Seed predation by naturally occurring beetles in farmland does have a beneficial effect, reducing weed numbers in fields and potentially improving agricultural productivity.”

Throughout the UK, 257 conventionally managed fields of sugar beet, maize, and spring and winter oilseed rape were examined to investigate the changes ground beetles cause in the amount of weed seeds in the seedbank. All weeds were reduced in fields of spring maize and winter oilseed rape, which the researchers attribute to the different communities of weeds and insects in these crops. In the other crops, grass weeds were reduced, even when broad-leaved weeds were more common.

“The ground beetles studied appear to eat a significant proportion of the weed seeds that would otherwise go into the seedbank. Within a careful pest management strategy, beetles could be used alongside and in place of some herbicide applications to significantly reduce weed populations, improve yields and help ensure future food security,” said Dr Bohan.