Switchgrass could be a major weapon in the fight against climate change

In a breakthrough study from the University of Texas at Austin, biologists are a giant step closer to making an inexpensive, renewable source of energy from a native North American plant called switchgrass.

The researchers conducted an advanced genome analysis of switchgrass, which revealed genes that could ultimately be key to the widespread production of biofuels. 

By linking various switchgrass genes to specific climates, the experts have essentially developed a guide for breeding switchgrass that will perform optimally under current and future climate conditions across the United States.

According to the researchers, optimizing switchgrass to grow efficiently in many different environments is key to ensuring its success as a biofuel feedstock.

Professor Tom Juenger has been on a mission to optimize switchgrass in his lab at UT Austin for more than a decade. When Professor Juenger analyzed samples provided by the U.S. Department of Agriculture’s switchgrass stocks, he noticed a lack of diversity. 

Study co-author David Lowry was a postdoctoral researcher in Professor Juenger’s lab when the research was initiated, and is now an assistant professor of Plant Biology at Michigan State University.

“Originally, a lot of these collections came from us driving around in a pickup truck with a shovel and digging up plants off the side of the road or in parks where we had permits,” said Lowry.

Switchgrass is a warm-season perennial with deep roots that grows all over the country. It is an important component of tallgrass prairie habitats, growing up to 12 feet in some regions, and is also considered to be one of the most valuable plants for controlling soil erosion.

Furthermore, switchgrass has recently gained a lot of attention as a potential source of biofuel, which is critically needed to address the climate crisis. 

In collaboration with experts at the Hudson Alpha Institute for Biotechnology and the DOE Joint Genome Institute, the UT Austin team created 10 identical gardens in eight states. They grew clones of more than 1,000 switchgrass samples collected from across North America. 

The researchers assembled a reference genome sequence to compare the diversity among the samples. They documented which varieties thrived and where, matching sections of their DNA with traits that evolved over millennia in response to specific climates.

“We ended up finding three very distinct populations of switchgrass from three regions of the United States, all of which had their own sets of adaptations to climate,” said study first author Alice MacQueen. “It means there are potentially multiple evolutionary paths available to match switchgrass plants to particular climates.”

The study is published in the journal Nature.

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By Chrissy Sexton, Earth.com Staff Writer