Climate change to encourage coffee pest: study

Reuters 3 Aug 09;

NAIROBI (Reuters) - Rising temperatures in the tropics due to climate change are likely to encourage the proliferation of the coffee berry borer, one of the crop's most devastating pests, a study released on Monday showed.

But reverting to an old way of growing coffee bushes under tree shade could reduce the temperature, it said. Shade also harbors the borer's predators.

"By analyzing climatic data ... the icipe-led team of researchers observed that the insect is capable of easily adapting to a wide range of temperature variations often found in coffee growing areas," a statement by the International Center of Insect Physiology and Ecology (icipe) said.

"Rising global temperatures will increase H. hampei (coffee berry borer) populations and in effect the damage it causes to coffee. Particularly devastating consequences are expected in coffee growing areas where the coffee trees produce fruits throughout the year, like Colombia," it said in a statement.

The research was carried out in Colombia, Kenya, Tanzania and Africa's largest coffee producer, Ethiopia.

The scientists also found that the geographical area susceptible to the black bug would increase to sub-tropical regions that were formerly unaffected.

However, the most suitable way for coffee production systems to cope with warmer temperatures would be to go back to the origins of the crop as an "understory" tree of the forests, the researchers said.

In Ethiopia -- considered to be the origin of the bean -- some coffee farmers still have their crop growing in forests.

In practical terms, large-scale producers may have to introduce taller shade trees in their estates, icipe said.

(Reporting by Helen Nyambura-Mwaura)