The ectomycorrhizal fungus Laccaria bicolor, shown in green, envelops the roots of a transgenic switchgrass plant. Switchgrass is not known to interact with this type of fungi naturally; the added PtLecRLK1 gene tells the plant to engage the fungus. Photo Source: ORNL, U.S. Dept. of Energy

A research team at the Oak Ridge National Laboratory (ORNL) has successfully introduced a gene from poplar into switchgrass, an important biofuel source, that allows switchgrass to interact with a beneficial fungus, ultimately boosting the grass' growth and viability in changing environments.

The researchers observed the ectomycorrhizal fungus Laccaria bicolor as it enveloped the plant's roots. This behavior, unknown to occur naturally between fungi and switchgrass, helps the plant to efficiently take up nutrients and water. This symbiotic relationship results in switchgrass that is more disease- and drought-resistant.

ORNL plant molecular biologist and geneticist Dr. Jin-Gui (Jay) Chen said, "We've engineered switchgrass to grow where it would typically struggle, that is, marginal land that is unsuitable for food crops. The fungus allows the switchgrass to absorb minerals from the soil." The team has identified the receptor gene that looks out for friendly fungi in a previous study.

For more details, read the article in ORNL News.