Bioenergy -- growing crops that can be used to generate energy (and possibly refined into chemicals) could be an important tool for mitigating climate change. But bioenergy can be controversial if it takes land out of food production or affects ecosystem services. A new $2.5 million grant from the U.S. Department of Energy will support work at UC Davis and the Oak Ridge National Laboratory to develop drought-tolerant poplar trees that can be grown on low-quality, poor and marginal land and used for bioenergy feedstocks.
"An important challenge is that trees are able to grow in drought-prone environments, which are likely to be more common in the future," said Gail Taylor, professor and department chair in the UC Davis Department of Plant Sciences. Taylor's laboratory is leading the effort in collaboration with geneticists Jin-Gui Chen and Wellington Muchero at ORNL.
"This is an exciting opportunity since poplar is both a model organism and one that can be deployed as a real crop in the field," Taylor said.
The researchers will first determine the ideotype or 'perfect tree' for droughted environments and then link this to underlying genomic targets that will be explored using the latest CRISPR-Cas9 gene editing tools, already developed for poplar.
"The research will benefit from over a decade of research in the U.S. and Europe that has selected more than 2,000 individual trees from naturally droughted environments across these two continents," said Taylor. This natural wild germplasm has been used in several DNA sequencing projects.
The project will include planting a new 10-acre field site at UC Davis to study tree responses to drought, including using the latest remote and proximal technologies such as unmanned aerial vehicles to assess canopy temperature. This will be complemented by the computational resources at ORNL.
The goal is to deliver new genotypes of poplar that are better able to tolerate droughted environments and that will be ready to test at multiple sites by the end of the project. At the same time, the genomic and genetic resources already available in poplar will be integrated into high throughput drought phenotyping and a complete atlas of gene expression related to drought stress for these natural populations.