EcoFABs Could Lead to Better Bioenergy Crops

by Will Ferguson (Berkeley Lab) A greater understanding of how plants and microbes work together to store vast amounts of atmospheric carbon in the soil will help in the design of better bioenergy crops for the fight against climate change.

Deciphering the mechanics of this mutually beneficial relationship is challenging, however, as conditions in nature are extremely difficult for scientists to replicate in the laboratory. To address this challenge, researchers at Lawrence Berkeley National Laboratory (Berkeley Lab) created fabricated ecosystems or EcoFABs.

In a new paper in Science Advances, they show how these takeout box–sized, plastic growth chambers could potentially provide scientists around the world with a standardized and reproducible platform for conducting experiments on model plants and the microbes that live around their roots.

This could in turn expedite research into the development of improved bioenergy crops capable of growing in nutrient-poor soils and absorbing more carbon from the atmosphere than is currently possible.

“The overarching idea behind EcoFABs is that there is a real need for a platform in plant microbiome research that enables scientists to better share data and build on each other’s work,” said Vlastimil Novak, lead author of the paper and a project scientist in Berkeley Lab’s Environmental Genomics and Systems Biology (EGSB) Division. “At the moment, there are around 20 laboratories that are using our devices, but we would eventually like to make them more broadly accessible to anyone in the world.”

For the study, Novak and colleagues in Trent Northen’s lab used EcoFABs to test how different forms of nitrogen affect the production of organic substances given off by the roots in Brachypodium, a small grass species used as a model for bioenergy grasses.

Nitrogen is essential for plant growth, and Novak noticed in the literature that its relationship with root exudation, or the types of compounds produced by a plant’s roots, had not been well explored in this grass species.

He and his collaborators conducted experiments supplying Brachypodium with different nitrogen sources – ammonium, nitrate, or a combination – and observed changes in root exudate composition. They found that varying levels of nitrogen affected the type of compounds produced by the roots and that the plants grew best when they received both ammonium and nitrate.

One interesting finding was the production of dopamine in the root exudates only when both ammonium and nitrate were present together. This suggests that specific nutritional conditions influence the production of certain metabolites which could in turn affect plant growth.

“The outcomes of this research can inform nutrient management practices, fundamentally saying that for Brachypodium or similar grasses, it is essential to supply both ammonium and nitrate simultaneously for optimal growth,” Novak said. “It also gives us ideas of some pretty interesting organic compounds in the root microbiome to investigate in the future.” READ MORE