Virginia Republican Wyatt B. Durrette, trying to shake off reports of dissension in his campaign for governor, said today that his race "is the next watershed" test for the GOP in the South.

It was the first time that Durrette has attempted to link his campaign with the national effort by Republicans to cut deeper into the traditional Democratic base in the South.

"It's going to be a test of whether or not Virginia and the South will continue their march to conservative principles," Durrette declared in his stump speech at the 9th Annual Atoka Country Supper here on the rolling estate of Sen. John W. Warner (R-Va.)

President Reagan's chief of staff, Donald T. Regan, guest speaker at the event, joined Durrette in placing a national focus on the Virginia elections. Regan said that the state's Nov. 5 balloting, coupled with the 1986 congressional elections, will be a "crucial test of our efforts in the White House."

"The president is going to be looking very closely at these elections," Regan told the crowd, estimated at between 2,000 and 3,000. He urged them to "win one, not only for the Gipper, but for Virginia and American's future."

Durrette previously had played down attempts to cast his race against Democrat Gerald L. Baliles, a former state attorney general, as a referendum on Reagan's presidency.

Despite Durrette's upbeat message today, several Republicans said they are worried that the pace and strategy of his campaign have failed to excite the party.

"I want them to throw some passes," said state Senate Minority Leader William Truban (R-Shenandoah), who said that the GOP campaign has been moving slowly.

Durrette's forces have been dogged in recent days by grumbling over their failure to agree on a precise strategy to employ against Baliles, and disputes over advertising and campaign fund-raising plans, but Durrette sought to brush off the complaining.

"I wouldn't define it as a problem," he said. "The people who advise me have different opinions."

Much of the day's events on Warner's farm centered on an old-fashioned picnic that featured barbequed chicken, cole slaw, pork and beans, and corn on the cob, while Dixieland and square dance music filled the cool air.

An indication of how serious these Republicans take their state politics came during the annual auction to raise money for the Federation of Republican Women. An American flag, flown over the U.S. Capitol on July 4, went for $100, but a Virginia state flag that flew over the state Capitol in Richmond sold for $140.

But the event drew a smaller crowd and raised less money -- about $57,350 -- than in recent years, according to spokeswoman Carolyn Peterson.

"It's safe to say that when Elizabeth Warner's former wife, Elizabeth Taylor was here, there was a certain magnet to draw people," Durrette acknowledged.

Several guests, appearing a little embarrassed, walked to Warner's large red barn and peeked inside. Many seemed surprised to find an oversized swimming pool, instead of horses and cows.

Most of the milling crowd missed one of the best shows that Atoka offers every year: the frantic efforts to keep dozens of officials and candidates for public office in order as they lined up in front of Warner's farm home to walk through the house and be announced to the crowd on the other side.