As the biggest textile and apparel trade show of the year opens this week in Atlanta, U.S. manufacturers continue to grapple with their greatest challenge: price competition from imports.

As more than 835 exhibitors representing 70 countries are slated to attend the four-day 1993 Bobbin Show, which is expected to attract about 20,000 visitors to the Georgia World Congress Center. Bobbin Magazine and the American Apparel Manufacturers Association are sponsoring the show.Forty conferences and seminars offered in conjunction with the show on topics ranging from manufacturing in the Caribbean Basin to international business etiquette are designed to enhance the competitiveness of the U.S. industry.

Carl Priestland, an economist with the manufacturers' association, said U.S. apparel makers continue to struggle against lower-priced imports.

With imports now accounting for nearly one-half of the U.S. apparel market, he said long-term prospects for the U.S. industry depend on how much access countries like China have to the U.S. market.

"China is capable of producing all the garments the developed world could use," he said. "If China has unlimited access to our marketplace, we've got problems."

China's legal textile exports to the U.S. totaled nearly $5 billion last year. The United States says China ships another $1.5 billion to $2 billion to it through third countries in violation of U.S. import quotas.

Overall, however, U.S. apparel imports from Asia's big four producing countries - China, Hong Kong, Taiwan and South Korea - have declined, Mr. Priestland said.

More U.S. apparel makers are shifting their offshore production bases from Asia to Latin America and the Caribbean because of what is known as Section 807, which offers duty incentives on imports of apparel made from U.S.-made cloth or cut fabric, he said.

Enhanced technology, some of it imported, is another way to compete globally, and the 1993 Bobbin Show will give U.S. manufacturers their first glimpse of how newly adopted computer-integrated manufacturing standards will affect their industry.