In a seven-acre plot of farmland south of the city, T. Mohan hunches over to weed the soil he recently planted with sesame. He just harvested his paddy crop, which - as it has for the past 30 years - had a good yield.
In three decades, Mr. Mohan has gone from a struggling paddy farmer to a prosperous one - using methods that are now discouraged by proponents of organic farming.
More than 30 years ago, India eagerly embraced the genetically engineered high-yielding seed stock, chemical pesticides, and fertilizers of the Green Revolution to combat frequent famines. Dams and irrigation projects were built, enabling farmers to plant two or more crops a year without being dependent on the vagaries of the monsoon.
The Green Revolution was so successful in India that it ramped up food grain production from 797 pounds per acre of cultivated land in 1967, when it began, to 1,697 pounds per acre in 2000. [Editor's note: The original version gave incorrect units of measurement for grain production.]
Now some of these gains that allowed India to feed itself are being challenged by the increasing European and American demand for organic food, from pesticide-free cashews to cold-pressed coconut oil.
The spread of organic farming in India is beginning to pit concerns about the supply of food for the masses against what are widely considered the environmentally unsustainable practices of the Green Revolution.
"The Green Revolution definitely had benefits but also many unwanted side effects that are becoming more apparent," says Gunter Pauli, founder-director of the Zero Emissions Research and Initiatives, based in Tokyo.
In India, organic farming received a boost at the start of the new millennium when the income potential of organic exports was realized. According to Dr. P. Bhattacharya of the National Center of Organic Farming, in Ghaziabad, India represents one tenth of the world's organic cultivation.
It may be more ecologically sound, but feeding India's bulging population of more than 1 billion people with organic crops alone has some experts worried about the increased risk of famine.
"That's a major problem. That has to be solved," says G. Vaidyanathan, manager of Enfield Agrobase, which pioneered organic farming in the state of Tamil Nadu more than a decade ago. Much of its organic cultivation eventually goes to the lucrative export market.
Experts estimate that 50 percent of India's organic crop is exported, while just 1 percent of the Indian population consumes organically grown food. "Affordability is a criterion because the prices are 20-25 percent more," says Vaidyanathan.
Mawite, who goes by one name only, runs an organic cashew farm a two-and-a-half hour drive south of Madras, in Auroville. According to her, organically grown food costs more because of the labor-intensive farming it requires.
"They spray inorganic cashew plantations twice a year and that's it. We have to prune, compost ... the soil base has to be good," says Mawite.
Dr. K. Mani, professor of production economics at the Tamil Nadu Agricultural University in Coimbatore, says Indian farmers, anxious about yields and demand, are unlikely to embrace organic production. Demand for organic food isn't high, he explains, because "price comes first and quality next" for the bulk of consumers here.
"We buy what costs less," says T. Daniel, who earns $37 per month working as a security guard in an apartment building not far from Enfield Agrobase's organic retail outlet. His extended family of eight consumes three to four pounds of rice each day. His mother buys the maximum rations from the subsidized public distribution system, where rice costs 70 percent less than in regular stores.
"It would be difficult for us otherwise," he says. The cheapest organic rice, meanwhile, costs nearly five times more than the conventional rice sold in markets.
Ashok Khosla, director of Development Alternatives in New Delhi, says organic prices are steeper because sellers are pitching to a different clientele who are willing to pay.
"The price has nothing to do with cost of production," he says.
He insists that in India, organic production generally costs less than modern farming because it requires fewer investments in equipment and chemicals.
He doesn't see organic and modern farming as incompatible. "Organic pest control by itself is probably not workable. Judicious use of chemicals may sometimes be required."
Mr. Khosla suggests that organic farming's intense labor requirement may be a positive attribute. "What's wrong with labor intensive? Wouldn't you rather have people working on farms than migrating to city slums in search of work?"
Khosla decried trying to produce crops that are not naturally suited to particular regions. Tanjavur, for example, is a water-scarce region that is used to grow rice, which is a water-intensive crop.
He suggests instead growing a nutritious variety of millet, called bhajra - which is more suitable to Tanjavur's natural conditions - and importing rice from water-rich areas. "Of course, you've got to do the [economic] calculations."
Pauli, of the Zero Emissions Research and Initiatives, goes a step further. "There is a need to do more with what the earth already produces, instead of trying to force the earth to produce more."