Joseph P. Yeldell, whose testimony in his first bribery and conspiracy trial last year was seen as critically damaging to his defense, declined to take the witness stand today -- thus abruptly ending the defense case in this retrial of the charges.

Yeldell's failure to testify, coupled with the absence of several expert witnesses who testified for the defense in the first trial of the case last October, showed a marked shift in the strategy of the attorneys defending the former D. C. Human Resources chief and his codefendant, multimillionaire developer Dominic F. Antonelli.

In the last trial, defense attorneys met many of the prosecution's allegations head-on, trying to refute them. That trial ended with guilty verdicts against both defendants. Both verdicts later were overturned.

In this retrial, defense attorneys Edward Bennett Williams and John A. Shorter Jr. abandoned this combative approach, leaving many of the prosecution's arguments uncontested, while trying to show that Antonelli's and Yeldell's actions were justifiable.

The surprisingly swift end of the testimony in the retrial of Antonelli, 57, and Yeldell, 47, means the jury deliberations could begin Wednesday, after the attorneys' closing arguments and the judge's explanation of the laws involved in the case.

Yeldell's decision not to take the witness stand resolved the only major question mark of these proceedings, which otherwise have been a streamlined replay of the first case.

Many observers of that trial felt that Yeldell's combative, often contradictory testimony was a major setback for the defense, and questioned whether his attorneys would risk a repetition of that performance.

That question was answered at 11:32 this morning when Yeldell's attorney, Shorter, walked to the lectern in front of U.S. District Court Judge Gerhard A. Gesell and said quietly, "Your Honor, the defendant Joseph P. Yeldell . . . rests." Shorter had not called a single witness in Yeldell's defense.

The new, low-key version of the defense case now depends heavily on how the jurors received the testimony of Antonelli, who remained quiet and unruffled during much of his six hours on the witness stand yesterday and today.

Repeatedly, Antonelli testified that there was no connection between the financial favors he had done for Yeldell, including a $33,000 secret loan that he gave the then-DHR director in 1976, and Yeldell's efforts in facilitating a $5.6 million, 20-year District of Columbia government lease on property controlled by Antonelli.

As Assistant U.S. Attorney Richard L. Beizer strode back and forth in front of Antonelli, firing a steady tattoo of questions on cross-examinations, Antonelli kept his head erect and answered every query in quiet, even tones.

"Each one of these two events (the loan and the lease) had a life of its own. They weren't intermingled at all," Antonelli said.

Later he reiterated, "one thing had nothing to do with the other."

Only when Beizer's cross-examination was nearing its end this morning did Antonelli appear disconcerted. At the time, the prosecurtor was standing at a large easel set up by the jury box and leading Antonelli through a line-by-line comparison of several rival lease offers the D.C. government was considering in the fall of 1975.

The leasing comparison was a key element in the prosecution's contention that Yeldell's interest in office space at 60 Florida Ave. NE was dependent on Antonelli's purchase of the property.

Several District of Columbia officials testified earlier in the trial that, when another potential purchaser of the run-down, two-story office building offered to lease it to the D.C. government, Yeldell's interest in the lease immediately evaporated.

Beizer set up his easel this morning in an effort to force Antonelli to testify that the rival offer-- which Yeldell spurned-- would have cost the city less money than Antonelli's lease.

As Beizer bent over to write down various numbers for the jury, Antonelli-- calculator in hand-- was adding up the cost of such items as maintenance and engineering costs, then giving these figures to his adversary across the room.

Throughout the calculations Antonelli maintained that his offer was the least expensive lease the District government could have obtained. When the figures on Beizer's easel contradicted that assertion, Antonelli first started to shuffle through the documents in front of him, then said the presecutor had made a mistake in setting up his calculations.

Much of the prosecutor's case against the two defendants is circumstantial, based on a series of coincidences in the timing of the leasing arrangement and of the financial aid that Antonelli gave Yeldell. The former DHR director had been left with large debts after the failure of a travel agency he had founded.

Antonelli first came to the aid of Yeldell's floundering business in 1973, guaranteeing $21,500 worth of loans for Yeldell at the Madison National Bank, which Antonelli had helped found and where he served on the board of directors.

In 1976, after Yeldell approached Antonelli asking for information about where he could obtain a second mortage on his house, Antonelli decided to loan Yeldell $33,000 himself, but concealed the source of the money.

"I didn't uant Mr. Yeldell to know I had advanced him the loan . . . I didn't want him to feel obligated," Antonelli said.

Closing arguments in the case are set to begin Wednesday at 9 a.m.