The incidence of coffee berry borer has been rampant in the 2008 Robusta coffee crop that has been harvested or being harvested now. As anticipated, the infestation is severe in the crop that is being harvested at the end of the harvesting season. The reasons for the spurt in incidence during 2008 are many.

The rainfall received during December 2007 across the coffee growing areas caused partial blossom leading to formation of off-season berries. The unusual early rains during February 2008 compounded the problem in the sense that harvesting was not complete at that time, buds started moving, and there was fruit drop and so more gleanings. As the rains continued without much break, it was not possible to effectively collect the gleanings and also to remove the left over fruits which dried up on the plant and carried full complement of adult berry borers in them to act as the source of inoculum for the next season’s crop. The arabica crop escaped with low to moderate level of infestation, but the robusta crop which has been harvested and is in the process of being harvested has been infested badly in many locations where the quantum of left over fruits were more and the gleanings could not be collected due to many reasons. If the rainfall pattern is analysed, the rainfall data available at the Central Coffee Research Institute shows that there was rain every month from February 2008 onwards, which compounded the problem of collecting gleanings and left over fruits from the fields.

During the current crop year i.e. 2009-10 the crop prospects look better and hence more care needs to be taken to manage the berry borer menace. It has not rained so far and so it is imperative that the remaining crop is completely harvested at the earliest. If any rainfall is received now, there may be fruit drop in the un-harvested fields leading to more gleanings to be collected. If harvest is not completed early, there will not be enough time or labour availability to concentrate on removal of left over fruits and gleanings.

Because the left over fruits, gleanings and off-season fruits are the inoculum carriers for the next seasons crop, all measures should be taken to reduce their presence in the fields. This is the key issue which every grower has to concentrate on without fail.

The “Broca” or berry borer traps can be installed now in the harvested fields so that the emerging beetles are trapped. As soon as the rains are received or when irrigation is given, there would be emergence of beetles from the left over fruits or the gleanings that are present on the estate. These beetles would be attracted to the traps. Traps installed in a particular field should be monitored at least once a week to assess the beetle catch. If the number is more, it indicates that the gleanings or left over fruits are still present in these plots. The traps installed should be inspected regularly to observe that the water in the reservoir (bottom half of the trap unit) is clean and the lure is not exhausted. If not inspected the accumulation of the beetles on the surface of the water would prevent other beetles from coming in contact with the water and getting killed and permitting them to escape into the field. Further, there would be a foul smell emanating from the dead beetles which may hinder further trapping.

The traps can remain in the field throughout the year except during the monsoon months of June, July and August. But the traps should be regularly inspected to check the availability of the lure material. During the monsoon months, the traps may be removed, cleaned and stored for later use.

If meticulous care is not taken to remove the leftover fruits and gleanings, it can aggravate the berry borer infestation on the next season’s crop and cause heavy damage.

The phyto-sanitary measures, if adopted by all growers would effectively check the berry borer menace. Since harvest is being completed in all the estates and measures are being taken to collect gleanings and left over fruits on the plants, it is quite possible that the damage due to berry borer in next year’s crop would be minimal. But then it requires a concerted and collective effort of all the growers.

DIRECTOR OF RESEARCH