News Plants

Defense hormones guide plant roots’ mix of microbes

Salicylic acid attracts some bacteria, repels others, study finds

roots of a weed called Arabidopsis thaliana

ROOT BOUND  The roots of a weed called Arabidopsis thaliana (shown) make a hormone called salicylic acid. That hormone attracts some bacteria to the roots while shooing others away.

HermannFalkner/sokol, Flickr  (CC BY-NC-SA 2.0) 

By Tina Hesman Saey

- More than 2 years ago

Plants help tend their own gardens. Salicylic acid, a plant hormone used to fight bacterial infections in leaves, also helps plants select which bacteria colonize their roots, researchers report online July 16 in Science.