Coffee plantations face a new problem after weathering a prolonged dry period. The incidence of white stem borer, a pest that attacks Arabica coffee plants, has flared up this year due to the prolonged dry period.

Growers feel the pest attack, which has resurfaced almost after four years, could possibly eat into the Arabica output for the 2012-13 crop year (October-September). However, they preferred not to hazard any guess at this point in time.

“White stem borer is a concern. Unable to tackle this menace, people are beginning to uproot affected plants,” said Mr Marvin Rodrigues, President of the Karnataka Planters Association (KPA).

Growers prefer to uproot trees and burn them to prevent the spread of borers to other plants as all other methods have been found to be ineffective in combating the menace.

Karnataka accounts for about 70 per cent of the country's coffee output and the incidence of borer is more pronounced in districts of Kodagu and to some extent in Chikmagalur.

Arabicas affected

The 2012-13 season starting October is an off-year for the Arabicas – a premium variety, where the crop size naturally shrinks every alternate year, said Mr Rodrigues. “The coming arabica crop will be down,” he said.

“It is the one of the worst attacks of the borer that we are seeing this year. Every year, we assume things are improving but the problem continues,” said Mr Bose Mandanna, a large coffee planter from Coorg. “Even the new variety of coffee – Chandragiri – introduced by the Coffee Board has not been spared. Its young plants have been attacked badly,” said Mr Mandanna, a former Vice-Chairman of the Board .

Growers have traditionally preferred to replace the affected Arabica plants with the sturdy variety Robustas.

“It is not a panic situation,” said the Coffee Board Chairman, Mr Jawaid Akhtar. The incidence of borer has been more this year compared to the last because of prolonged drought.

Climate changes

“It's too early to jump to any conclusion,” Mr Akhtar said commenting on the potential crop loss due to borer. The Board will come out with crop estimates in two months, he said.

“The climate change has led to change in the flight and breeding pattern of the white stem border. It seems to proliferate even more now,” said Mr A.K. Bhandari, former President of the United Planters' Association of Southern India.

“Concerns over the white stem borer are normal during a long dry period like this,” said Mr Ramesh Rajah, President of the Coffee Exporters Association.

“The climate change has led to longer dry period and delay in monsoon setting in. This has led to the borer spreading and increasing its infestation,” said Mr Bhandari.

The problem this time is that the borer attack is from below the ground. Till now, it was attacking from above the ground.

“Now, the borer seems to find space in the holes made next to the plant's stem by porcupines and ant eaters in coffee estates. These are at least two inches deep and the borer goes inside and hatches,” said Mr Mandanna.

“The borer menace can be curtailed once monsoon picks up. We doubt if it will take hectic proposition,” said Mr Bhandari.

Blossoms and showers

On the other hand, some areas have received good rains, particularly North Kodagu.

“The rain activity is good. The crop is likely to alright,” said Mr Bhandari. “The arabica crop looks good. Robusta will be similar to last year,” said Mr Rajah.

“The blossoming in arabica has been good. Robusta has also been helped by irrigation,” said Mr Bhandari.

“The damage (due to delay in rain) may not be as feared,” he said.

“It is early days yet. Rainfall in the growing areas has been adequate except in Anamalais in Tamil Nadu. We will be doing a survey in 2-3 weeks time to assess the crop,” said Mr Rajah.

During the current season ending September, coffee production has been estimated at a record 3.2 lakh tonnes with arabica making up 1.03 lakh tonnes and robusta the rest.

Last season, the production was 3.02 lakh tonnes (arabica 94,000 tonnes and robusta the rest).

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