Maryland, November 4, 2004 (ENS): An insect
specialist with the U.S. Agriculture Department is finding
new ways to fight the coffee berry borer, an insect
that threatens the quality of the bean that enlivens
the mornings for millions of people across the United
The tiny borer spends its entire larval life inside
the coffee berry, which encases the seed, commonly known
as the coffee bean.
Males mate with females inside the berry but never
leave it. Mated females emerge to fly to a new berry
and bore into it, lay eggs and start the cycle anew.
Only while outside the berry are the adult female borers
vulnerable to pest management methods.
One potential pest management method is the application
of Beauveria bassiana, a fungus that is pathogenic to
insects. The challenge is to get the fungus in contact
with an insect pest that spends most of its life inside
the coffee berry.
Agricultural Research Service entomologist Fernando
Vega and his colleagues at the Insect Biocontrol Laboratory
in Beltsville, found the fungus can become established
within plant tissue. The goal is to make the fungus
thrive in the coffee plant, exposing the borer to it,
Certain microscopic worms called nematodes may also
offer a method to control the borer. In collaboration
with scientists in Mexico, Vega found that when the
females of a particular nematode genus parasitized female
coffee berry borers, the result was not death, but a
reduction in reproductive efficiency.
Non-parasitized insects laid an average of 10 eggs,
but parasitized borers laid just two eggs on average.
Over time, this control method may help reduce the overall
Worldwide, coffee berry borers cause about $500 million
in damage to the crop annually. They eat holes in the
beans, lowering the crop's quality and reducing the
income of coffee growers.