Scientists studying a valuable, but vulnerable, species of poplar have identified the genetic mechanism responsible for the species' inability to resist a pervasive and deadly disease. Their finding, published in the Proceedings of the National Academy of Sciences, could lead to more successful hybrid poplar varieties for increased biofuels and forestry production and protect native trees against infection.
Hybrid varieties are economically valuable because they can grow up to three times faster than the pure species. If the hybridized poplars survive, they could dramatically increase production of high-value, bio-derived materials, biofuels and forestry products such as pulp and paper, lumber and veneer.
"Since the 1900s, industry has tried to grow hybrid varieties of poplar... and they have been puzzled by the early death of hybridized poplars grown in many parts of the United States," said Wellington Muchero, the study's lead author with the Center for Bioenergy Innovation at ORNL.
"Surprisingly, we found that a gene that causes susceptibility is widely prevalent across the species range," said Jared M. LeBoldus, senior author and assistant professor of forest pathology at Oregon State University.
To map the genetic behavior of black cottonwood, Oregon State scientists assessed more than 3,000 individual black cottonwoods using a combination of digital imagery and measurements of disease severity for susceptibility to Septoria canker. ORNL scientists used computational resources coupled with genome sequencing and profiling of more than a thousand genomes provided by DOE Joint Genome Institute that helped identify the resistance and susceptibility gene in each individual black cottonwood. The results identified individual trees that are resistant to the disease and can be used to develop resistant hybrids for commercial production.
Read more about this study at Science Daily.