We like the idea of plants chatting with each other using the dirt they live in as a kind of World Wide Web.
“Eww … whose roots are these? Did you hear about the caterpillars? Have you met the new germy-things that moved in down the row?”
So when Aaron Appleby, a senior studying organic agriculture at Washington State University in Pullman, summarized in a blog post a talk by Wenatchee scientist Mark Mazzola on how plants interact with soil microbes … well, that got our own mychorizza (tiny fungal-root arms) high-fiving with excitement.
Mazzola gave a presentation — “Understanding Soil Microbiology to Build System Resilience and Enhance Plant Productivity” — at the Tilth Conference held last November in Wenatchee. By the way, Mazzola is a plant pathologist with the U.S. Department of Agriculture’s Agricultural Research Service and is based at the WSU Tree Fruit Research Center in Wenatchee.
Appleby’s blog post was about what he learned from Mazzola’s presentation. Here are a few highlights:
- Soil that’s living and thriving with oodles of different microbes helps plants grow. In turn, those plants add back to the soil a whole bunch of organic material on which microbes live and thrive. A tidy cycle.
- Fungi exude chemicals to increase and encourage bacteria that produce a plant growth hormone called auxin, which boosts root growth.
- Soil can actually “remember” how it once thwarted a pathogen that attacked a certain crop. This phenomenon works best on mono-crop fields — no rotation of crops — where microbes that protected effectively one year can do their superhero thing the following year.
- So, yes, plants actually produce species-specific chemicals — or chemical cocktails — through their roots that “farm” certain beneficial populations of microorganisms that boost plant health or fight pests and diseases.
Want more info? Check out Appleby’s post at csanr.wsu.edu/plants-become-more-talkative/ or visit Mazzola’s WSU faculty page at www.tfrec.wsu.edu/pages/orgrte/Faculty/63.