The Hindu Business Line : New way to combat coffee berry borer

GLOBALLY, coffee berry borers cause about $500 million in damage to the crop annually. They eat holes in the beans, lower the crop's quality and reduce the growers' income.

A scientist of the Agricultural Research Service (ARS), an arm of the US Department of Agriculture, is finding new ways to combat the coffee berry borer, an insect that threatens the quality of the bean that provides refreshing aroma daily for millions of people worldwide. The tiny borer spends its entire larval life inside the coffee berry, which encases the seed or the 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 found by the scientist is the application of Beauveria bassiana, a fungus that causes diseases 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.

Mr Fernando E. Vega, ARS entomologist, and his colleagues at the Insect Biocontrol Laboratory in Beltsville, Maryland, found the fungus could be established within plant tissue.

The goal is to make the fungus thrive in the coffee plant, thus exposing it to the borer, according to Mr Vega.

Certain microscopic worms called nematodes may also offer a method to control the borer. In collaboration with scientists in Mexico, Mr Vega found that when the females of a particular nematode genus is made to live on the female coffee berry borers, the result was a reduction in reproductive efficiency.

While normal female borers insects laid an average of 10 eggs, the ones on which the nematodes lived laid just two eggs on average.

This, Mr Vega feels, could help control the overall population of the coffee borers over a period of time.