Foreground: microbial community under dry conditions (left) and microbial community under irrigated conditions (right)
Microbes deep in the soil influence plant health by releasing potent natural antibiotics such as PCA (phenazine-1-carboxylic acid). PCA-producing bacteria thrive on roots of dryland wheat throughout the Columbia Plateau, a major wheat-producing region in central Washington and Oregon, but their role in this important ecosystem was something of a mystery. Now the work of an international team of scientists provides direct evidence for the first time that these bacteria affect not only the wheat, but the soil around it.