Miscanthus towers above a man. Photo Courtesy of Mendel Biotechnology. |
Researchers
at the University of Georgia have taken a major step in the ongoing
effort to find sources of cleaner, renewable energy by mapping the
genomes of two originator cells of Miscanthus x giganteus, a large
perennial grass with promise as a source of ethanol and bioenergy.
Changsoo
Kim, a postdoctoral research associate in the UGA Plant Genome Mapping
Laboratory, identified a set of approximately 600 bits of Miscanthus DNA
that can serve as diagnostic tools. The next step is to determine which
pieces of DNA are diagnostic of genes that can make the plant an even
better biofuel crop.
Kim’s
work-and the Plant Genome Mapping Laboratory-is led by Andrew Paterson,
a Distinguished Research Professor who falls under the UGA departments
of genetics and plant biology in the Franklin College of Arts and
Sciences and crop and soil sciences in the College of Agricultural and
Environmental Sciences.
“What
we are doing right now is taking the same individual plants that were
used in the genetic map and measuring their height, flowering time, the
size of their stalks, the dimensions of their leaves and how far they
have spread from where they were planted,” said Paterson, who is also a
member of the Bioenergy Systems Research Institute. “And then one can
use pretty straightforward statistics to look for correlations between
bits of DNA and a trait.”
Miscanthus
is a natural candidate for biomass farming. Its sugarcane-like stalks
grow to more than 12 feet in height in soil of marginal quality; it
requires very little fertilizer; it grows well in moist temperate
climates across the United States, Europe and Asia; and in the eastern
U.S. it can produce more biomass on less acreage than other candidate
biofuel crops.
Miscanthus
is also a cleaner source of energy than fossil fuels. When coal or oil
is burned, it releases carbon that has been trapped under the earth’s
crust into the atmosphere, which is a major cause of global climate
change. Miscanthus removes carbon from the atmosphere as it grows. When
it is burned, it releases only the carbon it collected, effectively
making it carbon neutral.
Kim
and Paterson’s work will allow breeders to build on Miscanthus‘ natural
strengths and remove some of its weaknesses. For example, a significant
challenge to producing Miscanthus for biomass in the southeastern U.S.
is that it tends to flower too soon. Flowering requires nutrients and
energy that the plant would otherwise use to grow taller, thicker stalks
and leaves.
“You
don’t want it to flower,” Paterson said. “You’d like it to keep making
leaves and stalks and not bother with reproduction. Nature tells it not
to do that.”
The
genetic map will allow Kim and Paterson to locate Miscanthus genes
responsible for flowering and prevent it from happening too early in the
growing season. That will leave farmers with tall, hearty plants that
will yield the most biomass possible.
Their
efforts caught the attention of venture capitalists and biotechnology
companies that hope to make Miscanthus farming a profitable and
widespread practice. One company, Mendel Biotechnology, was so
interested in the potential crop they partnered with Kim and Paterson on
their Miscanthus project.
Mendel
distributes plants and plant seed that have been enhanced through
genetic research to farmers and other industry partners for bioenergy
crop production. “There is a lot of basic research that we cannot afford
to do,” said Donald Panter, senior vice president of BioEnergy Seeds at
Mendel. “We are a company that is trying to commercialize a product and
serve our customers, so our relationship to academia in the U.S. is
critical.”
The
genetic map promises to save Mendel many years of field research to
improve Miscanthus. Without the map, researchers and breeders must go
out into farmland and take thousands of measurements of plant
characteristics in many different locations to determine which plants
have the greatest potential as the beginnings of a biofuel crop. With
the genetic map, they can select the best plant varieties at the
molecular level much more rapidly.
“We
really want to leverage the know-how we get from American academia to
help us speed up the process of creating from nothing a commercial
species that can be planted on millions of acres in the next 10 to 15
years,” Panter said. “We wouldn’t be as far along the way if we didn’t
have people like Andy Paterson helping us.”
Large-scale
production of Miscanthus for biomass will take several years, but Kim
and Paterson’s research is an important initial step in the process.
“This
is just the beginning,” Kim said. “We want to provide breeders with a
valuable resource for their future breeding efforts. That’s our
long-term goal.”
