Even to the most orthodx Republican loyalist in California's farm-rich San Joaquin Valley, the Democratic National Committee was making an offer that could not be refused.

In exchange for campaign contributions, the DNC was saying, they could come to Washington, see the president, meet Cabinet officials, get to know their government better and talk about their problems.

As Berson (Burr) Frye, a Republican cotton merchant from Fresno, saw it, there was no mistaking the meaning.

"Regardless of the prevailing powers, we still have to deal with them. That's absolutely correct -- you are buying access. That's the way it is done," Frye said.

The merchandising of access -- bringing contributors together with administration officials -- figures prominently in the DNC's plans for building its 1980 campaign warchest.

Debbie Miller, director of the DNC's national finance council, said, "We will be doing it with more groups... Asian-Americans, Armenians. We want to give them access. But it's more of a social thing, parties which Cabinet secretaries attend, breakfasts."

Ursula Culver, assistant to DNC chairman John C. White, added: "There may be more, with other groups.The idea is to get people familiarized with government programs, get them to know government officials. I think it's a good idea for people to get involved, whether they are Democrats or Republicans."

Although the fine lines between "access" and "influence" often blur, White insisted recently that the DNC's new operations have nothing in common with practices during previous recent administrations.

Memberships in Lyndon B. Johnson's President's Club were sold for $1,000 and up, with government contracts frequently going to the more generous contributors. The Nixon administration was rocked by scandal over contributions by milk producers in return for higher government support prices.

The Carter White House also has been criticized. Last August, hours after an unannounced Oval Office meeting with the president, two California businessmen contributed $125,000 to the DNC. The Justice Department held that a law banning campaignfund solicitations in a federal building had not been violated:

Under the new DNC approach to providing access, about 90 contributore -- most of them Republicans with agribusiness interests in the Fresno area -- pointed up more than $50,000 to the DNC and flew here in January to meet high-level officials.

The Californians were eager because they had serious doubts about the administration's policies on water and reclamation land holdings -- policies that could cost them millions of dollars.

In Washington, they got a chance to shake the hands of President Carter and Vice President Mondale at a White House reception. They met with Agriculture Secretary Bob Bergland, Interior Secretary Cecil D. Andrus and other administration officials.

Less that three weeks later. the Interior Department announced it was waiving federal law and making federal water available for growing cotton on about 28,000 acres in the Westlands and San Luis water districts near Fresno.

Without the waiver from the 1960 San Luis water law, farmers in the valley could not have planted their cotton this year or last, when another waiver was granted.

The law prohibits the use of federal water for growing commodities declared in surplus by the Department of Agriculture -- which is the case with cotton.

There is no evidence of a cause-and-effect connection between Interior's decision and the Californians' visit to Washington bearing gifts for the Democratic Party.

Interior officials deny any likn between the events. Rep. Tony L. Coelho (D-Calif.), who represents Fresno County, claims credit for having persuaded Interior to go ahead with the waiver before his constituents made their contributions and came here.

"I raised the waiver issue with Bergland and Andrus in late December or early January," Coelho said. "It was resolved through my contacts with Guy Martin [an Interior assistant secretary] and Bergland. The group that came here wasn't aware of the waiver issue, but they did talk with Andrus about other reclamation maters."

But Rep. George Miller (D-Calif.), a critic of policies that have allowed agribusiness interests to accumulate illegal amounts of federally irrigated land in the valley, has asked for a General Accounting Office investigation of Interior's decision.

"You can't draw a 1-to-1 equation between their visit and that decision," Miller said, "but it's still the process of access. It's as clear as day -- they are paving the road to keeping their empire intact.

"The stakes are much higher than the cotton waiver. I have to ask to what extent the DNC will do their bidding when we come to dealing with the 160-acre landholding limit.

"It will not be just a congressional decision. A lot has to do with the White House. I fear they are merchandising their independence and it is a very bad mistake. There are other ways Demecrats can raise money."

The California contributors' comtacts with administration officials were not limited to the three-day Washington trip, arranged by Joseph Meredith, a DNC finance council member who lives in Fresno.

Some of them went to the Democratic midterm convention last year in Memphis and talked with Cabinet members. Others brunched with Andrus and Bergland earlier this month after the big DNC fund-raising dinner in Los Angeles.

"I want to have people interact with top policymakers," Meredith said. "You don't send a lawyer or a lobbyist to do that -- you send community leaders. The lobbyists will take over the country if we're not careful."

Among those with the most at stake over federal land and water policies are Paul and Octavia Diener, registered Republicans from Fresno County who farm more than 11,000 acres in the valley. The Dieners came to Washington with Meredith's group.

Diener said the Interior waiver would have little effect on the farmers who traveled here in January, but that there was good reason for conducting a "diologue" with federal executives.

"There is a lot of benefit in a dialogue between community leaders and government officials. It is good for government officials to know how we feel... They can't help but have a better understanding," Diener said. "Nobody's mind was changed radically, but we have to continue talking to them."