Archer Daniels Midland Co. said yesterday it has agreed to pay $100 million, the largest criminal antitrust fine in history, to the U.S. Treasury and to plead guilty to fixing the prices of two little-known ingredients that are widely used in modern food production.

The agreement marks the culmination of a global four-year Justice Department investigation into ADM, a giant agricultural company that has come to represent America's contribution to feeding the masses by billing itself as the "Supermarket to the World."

As part of the investigation, a top official in the company tape-recorded conversations for the FBI, and the Justice Department mobilized dozens of investigators around the world. The probe reached from the headquarters of the giant grain company in Decatur, Ill., to the Cayman Islands and beyond.

The agreement will resolve all pending criminal investigations of the company by the government, the company said. But the plea agreement is by no means the final chapter in the ADM affair. Two of the company's senior executives still are grand jury targets, according to the company. One of the targets is Terrance Wilson, 59, the head of ADM's corn processing division. But the central figure is Michael D. Andreas, 47, the company's vice chairman and once heir apparent to his father, company chairman and powerful political insider Dwayne O. Andreas, who has contributed millions of dollars to Republicans and Democrats alike and has cultivated foreign heads of state in his worldwide travels. {Related story on Page A7.}

Several large institutional investors yesterday called for the resignation of Dwayne Andreas, 78, who has ruled the company with an iron hand for nearly 26 years. Dwayne Andreas is not a target of the investigation.

"Dwayne, obviously, should go," said Patricia Macht, spokesman for the California Public Employees Retirement System, known as Calpers, which holds 3.6 million shares of ADM stock. "It's a lot like an apple -- if it's blemished on the outside, it's rotten at the core."

ADM did not comment about suggestions of such changes at the company, which some critics have said has been run like a family fiefdom by Dwayne Andreas and a board consisting of his friends or relatives.

ADM's products, from ethanol for automotive fuel to additives for animal feed and syrup for soft drinks, are ubiquitous and produced $13.3 billion in sales last year. Food products that use one or more ingredients from ADM include Doritos corn snacks, SnackWells cookies, Coca-Cola, Kellogg's Pop-Tarts, Ragu spaghetti sauce, Hamburger Helper and Premium Saltines. The company has more processing capacity than any agricultural company in the world.

Several antitrust experts said they were startled that the company agreed to such a large fine while two of its top officials are still in the Justice Department's sights. But criminal defense attorneys not involved in the case said the company had little choice. The government's evidence included not only tape recordings of international meetings with ADM's competitors during which prices and volumes of the products were set, but in addition, two international competitors recently pleaded guilty to price-fixing and agreed to cooperate in the case -- giving the government both the tapes and the co-conspirators in the crime.

Now ADM is in the awkward position of having to cooperate with the government in the investigation of its own chairman's son. Because of that relationship, the plea agreement was announced not by Dwayne Andreas, but by a special committee of the board of directors.

An attorney for Michael Andreas declined to comment on the case.

"I believe that when the dust settles, it will be clear that ADM and my client tried to bust open these international cartels, not fix them, and, in the process, saved American consumers millions," said Reid Weingarten, an attorney for Wilson, the head of ADM's corn processing division who also is a government target.

The fate of the government's mole, Mark Whitacre, is still to be determined. After ADM found that Whitacre, a top official in its bioproducts division, had taped hundreds of meetings with ADM executives, including Michael Andreas and Wilson, and the company's competitors, it accused Whitacre of embezzling $9 million from the company. The Justice Department began a separate investigation of Whitacre, who is expected to plead guilty to tax evasion and shareholder fraud soon. Prosecutors and defense experts said Whitacre is unlikely to be called as a witness if Michael Andreas and Wilson are charged and go to trial.

Justice officials declined to comment on ADM's announcement, which came on a day when federal offices were closed for the Columbus Day holiday. But sources close to the case said the Justice Department should consider the agreement -- which will be filed in a Chicago federal court today for its approval -- a victory.

"It's a significant milestone for the Justice Department," said Mark Gidley, a Washington antitrust attorney. "It's a whole new plateau for antitrust cases."

The largest fine Justice had previously leveled was for $15 million last year in a price-fixing case involving commercial explosives.

"Wow. They must have been really guilty if they're settling for that much," said Steven Kaplan, professor of finance at the University of Chicago's Graduate School of Business.

The antitrust investigation focused on whether ADM had illegally agreed to set certain prices and volumes for three major products made by Archer Daniels Midland and distributed internationally. The products are lysine, an animal feed additive that spurs the growth of poultry and pigs, and citric acid, a food additive that is used in soft drinks and as a preservative in prepared foods. ADM will pay a fine of $70 million for lysine and $30 million for citric acid. In addition, the company had previously settled civil lawsuits brought by the company's customers for $90 million.

As part of the criminal deal, Justice will not pursue charges that the company fixed prices in the third product, high-fructose corn syrup, a sweetener used in soft drinks such as Coke and Pepsi. HFCS, as it is known, is by far the product with the largest dollar market of the three products.

Because ADM supplies ingredients that are only one part of a final consumer product -- whether soft drinks or chicken legs -- it is difficult to determine what effect, if any, the settlement will have on consumer prices, said Tom Pirko, president of BevMark Inc., a New York beverage consulting firm. But consumers ultimately will benefit from the message that the government will not tolerate companies that conspire to fix prices, he said.

Corporate experts and Wall Street seemed to agree that ADM's deal was a good one for the company. The $100 million fine, while a record, will hardly make a dent in the bottom line of ADM, given its $13.3 billion in sales this year, they said. The company's stock was up to a 52-week high following yesterday's announcement, closing at $21.75, up $1.12 1/2. In shareholder terms, the fine represents a cost of less than 19 cents a share, according to several experts.

The deal is positive for the company in part because it will allow Dwayne Andreas to announce at the annual shareholders meeting Thursday that ADM's troubles are behind it, said John C. Coffee Jr., a law professor at Columbia University.

"It's fair to say the company faced overwhelming evidence of its guilt," Coffee said. "The urgency was spin control before the annual meeting. . . . . Now, the question is: Is the board so weak and passive that it will forget about this when there's reason to believe the vice chairman of the board and the head of a division will soon be indicted?"

If the government doesn't indict Michael Andreas and Wilson, he said, "it will look like the company paid $100 million to buy off the chairman's son."

While the government and the company might both think the deal is a good one, the group that suffers most is shareholders, said Sarah B. Teslik, executive director of the Council of Institutional Investors. "We have a situation where we {the shareholders} pay the government and the wrongdoers don't suffer," said Teslik, whose group is not calling for the resignation of the chairman. "What's so disturbing about corporate crime is that the individuals don't pay."

Powerful institutional shareholders, who control millions of shares of the company's stock, have been struggling for years to get the company to nominate directors who are outsiders -- those who owe allegiance only to the shareholders and not to Dwayne Andreas or the company. The current 12-member slate shareholders will vote on Thursday includes Washington lawyer Robert S. Strauss, former Canadian prime minister M. Brian Mulroney and F. Ross Johnson, chairman and chief executive of RJM Group Inc.

Analysts and corporate governance experts have said that the only way the company can truly repair its image after more than a year of high-profile charges and bad publicity would be for Dwayne Andreas and his top lieutenant, James Randall, 71, to resign. To put a good face on the move, it could be attributed to the ages of the two men, who are well past traditional retirement ages for executives, experts said.

The globe-trotting Andreas said in a telephone interview with The Washington Post earlier this year that he had no intention of retiring.

Michael Andreas, son of the chairman and vice chairman of the board, was long expected to succeed his father at the head of the company. But the investigations took him out of the running for the job, leaving the line of succession in question. CAPTION: ADM IN PROFILE A LOOK AT THE COMPANY AT THE CENTER OF THE PRICE-FIXING CASE WHAT IS ADM? Archer Daniels Midland Co., headquartered in Decatur, Ill., buys, stores, processes and sells agricultural products. In the 1996 fiscal year, it sold $13.3 billion worth of products. WHAT DOES ADM MAKE? ADM products include various oils and oilseed products, ethanol for automotive fuel, additives for animal feed and syrup for soft drinks. WHAT FOODS CONTAIN ADM PRODUCTS? Products that use one or more ingredients from ADM include Doritos corn snacks, SnackWells' cookies, Coca-Cola, Kellogg's Pop-Tarts, Ragu spaghetti sauce, Hamburger Helper and Premium Saltines. WHAT DOES THE COMPANY DO BESIDES SELL AGRICULTURAL PRODUCTS? The self-described "Supermarket to the World" has more processing capacity than any other agricultural company in the world. Every day it operates 165 plants, 300 grain elevators, 10,000 railroad cars, 15,000 trucks and 2,000 barges. WHO RUNS ADM? Dwayne O. Andreas, 78, the powerful, globe-trotting friend of politicians, has run ADM for almost 26 years. The board of directors includes such well-known figures as Washington lawyer Robert S. Strauss, former Canadian prime minister Brian Mulroney, Mrs. Nelson A. "Happy" Rockefeller and F. Ross Johnson, chairman and chief executive of RJM Group Inc. CAPTION: Andreas