BLACKSBURG, Va., July 12, 2005 – Brett Tyler, research professor at the Virginia Bioinformatics
Institute (VBI) and Virginia Tech professor of plant pathology,
physiology, and weed science, has been awarded a three-year, $980,000
grant from the United States Department of Agriculture (USDA) to
identify the ways in which the plant pathogen Phytopthora sojae
overcomes the defenses of its host soybean.
Phytophthora species and related pathogens cause tens of billions
of dollars of damage every year to a wide range of both agriculturally
and ornamentally important plants, and also cause severe damage to
forests and threaten entire natural ecosystems. More specifically, P.
sojae causes serious damage to soybean crops and cost growers $1
billion worldwide in 2003. In order to develop improved methods for
controlling Phytophthora infection, it is important to understand how
these pathogens break down plants’ defenses in order to develop plants
with improved resistance against the pathogen.
Many of the most important interactions between the pathogen and its
host occur early in the infection process. Tyler and co-project
director Kurt Lamour, assistant professor of entomology and plant
pathology at the University of Tennessee, Knoxville, will focus on
identifying and characterizing genes active at the earliest times
during P. sojae infection, starting with spore germination and
penetration of the host, and continuing through the first 16 hours of
infection. This time period is the most crucial for a successful
infection because this is when the pathogen seeks to establish itself
within the host tissue. Collaborators Michael Scanlon at the University
of Georgia, and Hayes McDonald at the Oak Ridge National Laboratory
will also assist in the study.
“A complex web of interactions between pathogen and plant genes
occurs during the first hours of infection as the two organisms battle
for supremacy,” Tyler said. “By taking a whole genome approach that
measures the activities of all the pathogen and plant genes
simultaneously we can begin to tease apart this web.”
Last year, Tyler and his colleagues successfully mapped the genomes
of P. sojae and its sister pathogen, Phytophtora ramorum. P. ramorum,
more commonly known as sudden oak death, is a serious fungus-like
pathogen that has attacked and killed tens of thousands of oak trees in
California and Oregon. These genome sequences are serving as important
tools in combating these devastating diseases.
July 11, 2005