Root Microbiome Engineering Improves Plant Growth
Root Microbiome Engineering Improves
Plant Growth
Only a few published studies have
looked at the effects of artificially selecting microbiomes. In their own labs,
the authors--Ulrich Mueller of the University of Texas at Austin and Joel Sachs
of the University of California, Riverside--have seen microbiome engineering to
be successful with Arabidopsis (a close relative of cabbage and broccoli). In
the Arabidopsis experiments, bacteria from the roots of the largest plants were
harvested with a filter and given to other plants growing from seed. Over time,
the plants, which were genetically identical and therefore could not evolve by
themselves, grew better because of their evolved and improved microbiomes.
"My hope is that others will
become interested in optimizing methods in other systems," says Mueller.
"For agricultural applications, I would start with artificial selection of
root microbiomes in a greenhouse environment, using cash crops such as lettuce,
cucumber, or tomatoes, learn from these greenhouse experiments, then gauge
whether any of these principles can be applied to outdoor agriculture and
horticulture."
Microbiome experiments can be
tricky and affect reproducibility because of the complexity of propagating
entire microbial communities between plants or between animals. The reason
grasses and honeybees are attractive pilot organisms is because their
microbiomes can be manipulated to be heritable. By testing this in organisms
with stable genetics, it is easier to see the effects of adding specific
bacterial communities.
"Selecting artificial
microbiomes may be a cheaper way to help curb plant and animal diseases rather
than pesticides and antibiotics or creating genetically modified
organisms," Mueller says. "The methods to generate host-mediated
artificial selection on root microbiomes are super simple (all you need is a
syringe and a filter), and any farmer in any location could potentially do this
to engineer microbiomes that are specific to the problems of the specific
location where the farmer attempts to grow food."