RANGAPARA, India -- D.K. Subba took a long, loud slurp, rolled the orange pekoe over his tongue and promptly spit a stream of coppery brown liquid into a metal can.


"Prices are disastrous this year," said the manager of India's Empire Tea Plantations, returning the white china cup to the tasting table. "I keep telling my people, 'Quality is now the word. It's the survival of the fittest.'"


The tea industry in the world's largest tea-producing country is facing its worst crisis in modern times. Stripped of its biggest customer with the collapse of the Soviet Union and battered by mounting international pressures from the United States and Europe over child labor, harmful pesticides and inferior teas, India has watched its tea prices and exports plummet to record low levels.


The nosedive in the Indian tea market, the country's largest generator of foreign exchange, is forcing major changes in the 150-year-old, tradition-bound industry. Many industry experts say those changes eventually could mean better tasting, less toxic but more expensive teas on the breakfast tables of the United States and Europe, as well as in the roadside tea stalls of


India.


Savvy growers already have begun concentrating on developing higher quality bushes and better yields. Earlier this year, one grower saw the first results of several years' work: a first-flush Darjeeling sold for a record $164 a pound (about $360 per kilogram). The average price for Indian tea this year, however, has been about 58 cents a pound, down 18 percent from last year.


For a nation that has used tea to bolster its foreign exchange, pay its weapons debts and help maintain its image as a world leader in the international tea markets, the decline of its tea industry could be devastating.


Indian tea officials have watched with dismay as Sri Lanka has stolen the title of the world's largest tea exporter from its giant neighbor for the last three years.


"We had become too complacent," said H. P. Baruah, recent past chairman of the Indian Tea Association. "The market is very competitive. We should be on our guard."


Subba, a perfectionist after 31 years in the tea business, patrols his lush green plantations in central Assam State in India's far northeast with an even more critical eye than usual these days. His pluckers, mostly women, seem to float through a waist-high emerald sea of leaves, fingers snapping the fresh young leaves at the top of the plants. If they are too big, the leaves are too tough; if too small, they are not economical.


``You have to maintain the tops like a billiard table,'' said Subba, pointing across row after perfectly even row of tea plants. In his nursery Subba is placing high hopes on a new strain of tea, clinically dubbed TV29, that, if it lives up to its billing, could produce twice the amount of quality leaves as the 25- to 90-year-old bushes now in his gardens.


Inside the processing factories, where freshly cured tea leaves are taste-tested every hour, Subba and his managers pore over the color, liquor and taste of his tea varieties with the same fervor as French wine tasters.


But the Indian tea industry is also under assault from socially and environmentally correct lobbying groups in some of its more promising new markets. Germany, a nation that pays top dollar for high-quality teas and buys an average of 4,400 tons of Indian tea each year, recently began rejecting Indian teas when German tests indicated Indian growers were using too many lethal pesticides.


"Germans are very finicky," said P. K. Bhattacharjee, secretary of the Assam Branch of the Indian Tea Association, which represents about 270 gardens in Assam, India's biggest tea-producing state. "Now we have to be very careful of pesticides."


But the single greatest blow to the Indian tea industry has been the loss of its biggest customer and the world's largest tea-importing nation, the former Soviet Union, which bought 50 percent of all the tea exported from India.


As India's biggest commercial and military trading partner, the Soviet government bought massive quantities of tea in exchange for Indian debts on arms and other purchases. When the Soviet Union disintegrated, India's tea sales to Russia and other former Soviet states plunged 70 percent.