Several influential senators warned yesterday that the fate of the Panama Canal treaties depends on the Carter administration's ability to resolve apparent contradictions in U.S. and Panamanian interpretations of key defense provisions in the agreements.

That message was delivered with unmistakable force at a hearing of the Senate Foreign Relations Committee. There, a parade of senators whose support is considered crucial to the treaties warned that the pacts have no chance of approval without unequivocal assurances from both governments that the treaties safeguard future U.S. military rights in the canal.

Spurring their concern was the disclosure by Sen. Bob Dole (R-Kan.) on Tuesday of a confidential State Department cable from the U.S. embassy in Panama. Dole's appearance as a witness before the committee yesterday made discussion of the cable's contents the dominant topic of the hearing.

The cable described one of the Panamanian treaty negotiators. Carlos Lopez Guevara, as privately disputing contentions that the treaties give the United States the rights to intervene against threats to the canal and to obtain priority passage for U.S. ships in time of war.

Previously, top administration officials - Secretary of State Cyrus R. Vance. Defense Secretary Harold Brown, Gen. George Brown, chairman of the Joint Chiefs of Staff, and the two U.S. negotiators. Ellsworth Bunker and Sol M. Linowitz - had assured the committee that these rights were fully guaranteed by the language of the treaties.

These apparent divergences triggered yesterday's demands by committee members for quick clarification. Summing up what appeared to be the dominant Senate attitude was Sen. Frank Church (D-Idaho), who is officially uncommitted but privately regarded as leaning toward approval of the treaties.

"Let it be clear the that Senate is not likely to ratify these treaties if crucial provisions are being interpreted differently by the principal parties," he said. "These are crucial provisions, and if there is a different interpretation being placed on them by the government of Panama, now is the time to find out."

"I hope that message gets through loud and clear," Church added pointedly. "Otherwise, this is going to become a tangle and a morass and result in a legislative catastrophe."

Another uncommitted senator, Richard B. Stone (D-Fla.), put the matter differently. Talking with reporters during a break, Stone said: "It's time for the State Department and the Panamanian government to get their act together and tell us whether they're in agreement on the meaning of these treaties."

These demands have posed a serious problem for the administration in its uphill fight to win the 67 votes - two-thirds of the Senate - required for approval of the treaties.

They have to contend with the fact that the treaties are a highly sensitive domestic political issue in Panama as well as in the United States. In fact, the ambiguous language in the treaties causing the current dispute over interpretation represented a government of Panama's military ruler. Gen. Omar Torrijos, from charges it made too many concessions to the United States.

So far, the administration's only answer to the swelling Senate demand for clarification was the sending of a letter yesterday by Acting Secretary of State Warren Christopher to the Foreign Relations Committee.

In it, Christopher reasserted, "The explanation of the Panama Canal treaties offered by administration witnesses before your committee last week is accurate."

The letter said that while the United States does not claim any right to intervene in Panama's internal affairs, it does have the right under the treaties "to take any appropriate measure to defend the canal" against future threats to its neutrality.

However, Christopher's letter did not say that the Panamanian government has acknowledged this interpretation as correct. It also failed to say anything about whether Panama agrees that the treaty provisions of "expeditious passage" for U.S. ships mean that they "go to the head of the line" in passing through the canal.

These points were hammered at by Dole, who, in his testimony, said they prove the need for the Senate to amend the treaties in ways that will leave no doubt about their meaning. Dole has introduced six proposed amendments and two so-called "reservations" that he says should be tacked onto the treaties to increase protection of U.S. interests.

The administration is on record as opposing any amendments or reservations because such changes would require new negotiations with Panama to obtain its consent. In his testimony, Dole conceded that the State Department had informed him it found all of his proposed changes unacceptable.