The Senate Judiciary Committee yesterday approved President Carter's nominations of two black U.S. district court judges, including the first to be named in the South.

The names of Robert F. Collins, a New Orleans magistrate, and Jack Tanner, a Tacoma, Wash., attorney, will now go to the Senate floor for confirmation.

Collins was approved 13 to 1 after Sen. Russell B. Long (D-La.) appeared before the committee and urged members to "measure up to the challenge and consider this man the way you would any other nominee."

It was the committee's second vote on the Collins nomination. The first vote resulted in a tie.

Sen. Dennis DeConcini (D-Ariz), who presided at closed hearings in February, said the panel heard allegations that Collins had misused his office for personal favors and charges of "involvement of substantial amounts of money in political campaign."

"I determined there was no basis for either of the charges," DeConcini said.

The Arzizona senators told the committee he nevertheless voted against confirmation of Collins the first time because "having seenthe man and talked to him, I couldn't in conscience vote for him on grounds of competence and capacity."

DeConcini was the only senator to vote no yesterday.