Earthworms contribute to 6.5 percent of world grain production

PARIS: Most gardeners know that earthworms help keep soils healthy, now scientists have assessed just how important their underground activities are to global food production -- and how to protect them.

In research published on Tuesday scientists found that earthworms may be to thank for more than six percent of global grain yields every year, because of their crucial role in soil ecosystems.

Worms help to decompose dead plant material, releasing nutrients plants need to grow, and their tunnelling helps plant root growth among other benefits. Evidence suggests they also help plants protect themselves against common soil pathogens by stimulating their defences. But they are threatened by today´s intensive and chemical-heavy agricultural techniques, scientists say.