Beaumont, Texas
July 20, 2004
The Mexican rice borer, a serious
pest of rice and sugarcane, is rapidly moving east through the
Texas Rice Belt toward Louisiana’s high-dollar sugarcane
industry.
Migrating up from Mexico, the
Mexican rice borer was first discovered in Rio Grande Valley
sugarcane in 1980. It quickly became a devastating pest,
causing some farmers to forego the harvesting of entire fields.
Over the next two decades, the insect gradually moved northeast
and during the 1990s, it became a serious threat to rice.
Since the insect does not
recognize state boundaries, entomologist Dr. Mo Way at the
Texas A&M University System
Agricultural Research and Extension Center in Beaumont, and Dr.
Gene Reagan with the Louisiana
State University AgCenter, have teamed up to help farmers in
both states combat this pest.
The collaborative research
project began in 2000. According to Way, only a portion of the
work has involved insecticides.
“The main research focus has been
toward the development of cultural and production practices,
together with varietal resistance, to reduce pest problems with
the Mexican rice borer,” Way said.
Another factor, which emphasizes
integrated pest management, balances the use of diverse control
tactics.
“If any single control tactic can
be reduced, the selection pressure on the pest population is
also reduced,” explained Way, “and this enhances the long-term
success in controlling the pest.”
This system often includes the
use of biological controls to conserve beneficial insects, such
as predators and parasites, which frequently contain pest
populations below damaging levels.
The researchers are also seeking
to develop a Mexican rice borer- resistant variety, that would
be less attractive to the adult female for egg-laying.
Greenhouse studies are also being
conducted at the Texas A&M University System Research and
Extension Center in Weslaco to determine the insect’s egg-laying
preferences in certain varieties of rice and sugarcane.
Varieties of rice have been tested in the field to assess
differences in stem borer resistance with respect to planting
dates. Early research indicates that modifying the planting date
may help lessen the insect’s impact.
The initial emphasis of
collaborative studies on the Mexican rice borer was determining
the pest movement through Texas rice acres. In 2000, yield
losses of more than 50 percent in treated and untreated
experimental plots in Ganado underscored the seriousness of the
problem.
With the help of Extension
agents, farmers and the Texas Department of Agriculture, the
researchers have recorded insect movement into several Texas
counties. For example, in Galveston County, 2,069 insects were
collected in 2002, and 3,755 in 2003.
“Even though our trapping did not
reveal any newly-infested counties in 2003, the increases in
numbers can be interpreted as a signal that the pest continues
to build populations and spread into new areas,” Way said.
As the Mexican rice borer spreads
into new areas and new cropping systems, multi-state
interdisciplinary collaborative work will become more important.
Since its inception in 2000, the
collaborative effort between Way and Reagan has brought in more
than $500,000 in national funding through the U.S. Department of
Agriculture Cooperative State Research, Education and Extension
Service.
“This stem borer respects neither
commodity nor political boundaries,” Way said, “and successful
management of the pest must emphasize an area-wide approach. To
provide the greatest benefit to our producers, we want to
develop and implement practices that not only protect the host
crops, but also reduce pest populations throughout the region.” |