The nation's most able teachers could be paid as much as $70,000 annually if teachers' unions agree to methods of testing or evaluating educators in public schools, Tennessee Gov. Lamar Alexander (R) said yesterday.

Alexander also predicted that taxpayers would support such salaries to educate students to compete in the next decade with Soviet and Korean students.

Alexander said Soviet students study 200 days a year and that Korea, "already the most literate nation in the world," will soon outperform the United States in the world marketplace.

"It may sound ridiculous to say it, but the quality of our teachers in the '90s will decide the future of America," he said. "It's that crucial."

Alexander was one of four panelists on NBC's "Meet the Press" discussing last week's Carnegie Foundation report outlining ways to revamp the nation's educational system.

"The whole problem boils down to whether the teachers' largest union National Education Association and the teachers themselves can accept our finding ways to pay some teachers more than others," said Alexander, chairman of an education project for the National Governors Association.

If that happens, some teachers could look forward to salaries from $50,000 to $70,000 a year, "and American taxpayers will pay it because they know their jobs depend on it," he said.

"The American people will pay more for education, but they have to see performance as a condition of paying," said Education Secretary William J. Bennett, whose reaction to the report was "generally very favorable."

Carnegie's Task Force on Teaching as a Profession recommended eliminating the undergraduate degree in education, establishing a national board to certify new teachers, creating a level of "super teachers" with more experience and higher pay, and establishing a controversial merit-pay plan to reward schools based on student performance.

NEA President Mary H. Futrell, a panelist, said that although her organization disagrees with the merit-pay concept, she signed the task-force report because it also recommends more money for education, more power for teachers and a certification system for teachers similar to those for lawyers or doctors.

Albert Shanker, president of the rival American Federation of Teachers and a supporter of a new certification program, said, "Most of the state teacher exams that exist now are just jokes. They're not professional exams at all."

He added, "If all other professions do it on the basis of national examinations, we should do it the same way.