By Debiprasad Nayak The Wall Street Journal May 21, 2012 MUMBAI – An extended dry spell in India's main coffee growing regions has promoted the spread of a crop pest, which is threatening next marketing year’s output, industry executives said Monday. The white stem borer affects mainly arabica crops, which farmers uproot and destroy to prevent further spreading. Outbreaks spread quicker during prolonged periods of dryness. "The incidence of white stem borer was slightly lower [than normal] in the last three-four years. But this year it is about 25% higher than normal in most areas," Karnataka Planters Association Chairman Marvin Rodrigues said. The South Indian state of Karnataka is the country's largest coffee producer, accounting for 70% of national output. Its neighboring states of Kerala and Tamil Nadu are also large producers. The fall in production isn't likely to buttress prices, as demand has been weak due to the sputtering glob...