Leaders of a nationwide farm strike said yesterday that Secretary of Agriculture Bob Bergland could not understand farmers' problems and should resign.

Gene Schroder said members of the American Agriculture Movement, which started the farm strike Dec. 14, were angered by Bergland's comments to the American Farm Bureau Federation convention in Houston.

Bergland told the farm bureau Monday night the farmers' demand for 100 per cent parity was unacceptable because it would require massive government payments or total government control of the marketplace.

"It now appears that Bergland doesn't understand what we're saying," Schroder said. "Because of this we feel like it would be appropriate for Secretary Bergland to step aside and that we appoint a smarter man who can understand the problems."

Schroder said it was "very difficult to work with someone who doesn't understand the program. This [Bergland's resignation] is probably the only solution. We simply can't work with a man like this."

The full parity demanded by striking famers would cost the government $44 billion and would force the price index for food by almost 20 per cent above current expectations, according to a University of Pennsylvania study.

The predictions came in the annual Agricultural Forecast of the Wharton Econometric Associates at the university Monday.

The estimated costs of 100 per cent parity far exceed the expected $25 billion tax cut reportedly being considered by the Carter administration as an economic stimulus.

At full parity, farmers theoretically have the same purchasing power for the items they sell as their forebears had early in this century when prices and costs were said to be in step. Farm prices as of Nov. 15 averaged 66 per cent of parity, one of the lowest marks for the indicator in 44 years.

Bergland told the farm bureau 100 per cent parity would mean a "system of bureaucracy that is too much like the system in the Soviet Union, which is rigid and unresponsive.

"When you get into government guaranteeing, you're looking at disciplines that no one is prepared to accept," he said.

Schroder likened the farmers' demand to the federal minimum wage. He said this didn't guarantee an income, only an ability to earn an income.

He said 100 per cent parity would not cost the federal government anything and would not require a large bureaucracy.