College Station, Texas
August 10, 2004
Her perseverance in learning
English and in earning two graduate degrees in a foreign country
have made her a formidable foe for a tiny enemy of Texas' rice
industry.
As a child in Sri Lanka, Dr. Bandara Ratnayake devoured books in
English. The titles behind the names of the authors – "M.S." and
"Ph.D." – impressed her. That determination to receive more
education would help her earn a master's degree and a doctorate
from two universities in the United States.
In May, she earned a doctorate from
Texas A&M University after
several years of balancing school and research in College
Station and Beaumont, as well as time with her family. Her
tenacity paved the way for more research on host plant
resistance to the rice water weevil. Because of her work,
scientists may now be able to identify proteins that are toxic
to the insect and develop genetically-altered rice varieties.
The rice water weevil is about as long as a pencil eraser. The
adults' feeding on the young rice foliage causes scars on the
upper leaf surface.
But the larvae cause the real damage. They live underground in
the saturated mud and obtain oxygen by piercing the rice plant's
roots with spiny projections.
They prune rice roots and cause stunting, delayed maturity,
reduced tiller production and increases competition from weeds.
Rice water weevils cause an estimated $40 to $120 in damage per
acre in a season.
The primary control of the rice water weevil is insecticides;
other methods of cultural and biological control have met with
little success.
Plant resistance to the pest offers "savings in production costs
and a reduction of the pesticide load in the environment,"
Ratnayake said.
Scientists are developing a rice variety with genes containing
proteins toxic to the pest.
"In order to continue the research, the best strategy would be
to select a toxic protein against the rice water weevil larvae
and insert that gene into rice," she said.
But before that can be done, the insect has to be studied even
further since little research has been done on its basic
biology.
To study most insects, researchers must raise large populations
of the object of study in labs. But to do so requires artificial
diets, and none was available for the rice water weevil.
"Ratnayake has forged toward success in the development of an
artificial diet specific to the rice water weevil," said Dr. Mo
Way of Beaumont, entomologist with the Texas Agricultural
Experiment Station and her research advisor.
Ratnayake tested more than 25 artificial diets, but the larvae
live underground in mud.
"When bringing the natural environment into the laboratory,
microbial agents from the mud contaminate the artificial diet,"
Way said.
"Progress on developing an artificial diet has been made,"
Ratnayake said, "and continued work is needed. To my knowledge,
this is the first attempt to develop an artificial diet for the
rice water weevil."
Ratnayake was able to develop reliable testing techniques to
screen the proteins toxic to the larvae. She also developed a
method to produce a large number of rice water weevil larvae for
laboratory research.
Ratnayake earned her undergraduate degree in entomology in Sri
Lanka.|
She worked for the Sri Lanka
Department of Agriculture in a farmer field school educational
program for eight years until she and her husband, Sunil, moved
to Mississippi. Sunil came to the United States to continue his
education, so she did the same, first taking English courses and
then working on a graduate degree in entomology. She completed
her master's degree in 1995 at Mississippi State University and
started working on her doctorate.
In 1998, Sunil took a job in Houston, and then began teaching
biology at Blinn College in Bryan. Bandara, who had stopped
working on the advanced degree in Mississippi when they moved,
began working on it again in 1999 at Texas A&M.
She is thankful to her mother and her sacrifices through the
years. Her mother moved to the United States to help take care
of the Ratnayakes' children so Bandara could study.
Also, she is grateful to Way and to Dr. Jim Olson, her academic
advisor and also an Experiment Station entomologist, for their
encouragement, understanding, guidance and support throughout
her studies.
Without all of the support she received, "I couldn't have done
it," she said. "When I look back, I think it was a long journey
with lots of hard work."
Part of the challenge has been the fact the rice water weevil
appear only for about three-and-one-half months per year, and
could not be raised in a laboratory. So each summer for four
years, Ratnayake would pack up her family and move to the Texas
A&M System Research and Extension Center in Beaumont to study
the insect in its natural environment. Her husband would come
down on weekends.
She admitted it was hard on the children. "They had to leave
their friends and customary summer activities. My family
sacrificed for my studies."
Her daughter, Anu, 19, is pursuing her undergraduate degree at
Texas A&M. Her son, Charith, is 8 years old.
What's next? Ratnayake hopes to continue with post doctoral
studies at Texas A&M.
"In my mind, I want to be an entomologist with a strong academic
background," she said.
"She will no doubt make a mark in the entomological scientific
community," Olson said.
Ratnayake received financial support for her studies from Texas
rice farmers and RiceTec Inc.,
a private hybrid rice seed producing company in Alvin. |