HARVEST OF SUBPOENAS

WHISTLE-BLOWERS COME IN ALL different styles, but they don't tend to be the boss's choice to inherit the top job. Mark Whitacre, 38, was just such a favorite at giant Archer Daniels Midland, the company that calls itself "supermarket to the world" because its products range from flour to vegetable oil. So close was Whitacre to ADM chairman Dwayne Andreas that the older man regarded the younger as a "second son." And as if to emulate his mentor, Whitacre lived in a colonial-style mansion in Moweaqua, Illinois, that Andreas once owned.

But the heir apparent was leading a double life. To his colleagues, Whitacre was a dedicated company man who supervised a fast-growing division that extracts profitable nutrients like vitamins from grain. But he also served as an FBI mole in an investigation of possible price-fixing at the firm. According to a story broken last week by the Wall Street Journal, Whitacre alerted federal authorities to possible collusion between ADM and other companies in 1992, and was outfitted with a briefcase with a hidden recorder. Since then, the Journal said, the FBI has collected audio- and videotapes of hundreds of meetings between ADM and other firms in hotels in cities from Los Angeles to Tokyo.

Just as corporate executives across America were digesting the idea that a major U.S. company could be infiltrated at the highest level by the FBI another tantalizing aspect to the case emerged. Howard Buffett, ADM vice president for public affairs and son of billionaire investor Warren Buffett, had quit a week earlier, apparently distressed about the investigation and the company's handling of it.

Little is known about the alleged price-fixing scheme. But a federal grand jury in Chicago has cast a wide net to determine who might have participated. In recent weeks, the grand jury has subpoenaed possible evidence of collusion from agribusiness behemoths Cargill, CPC International and A.E. Staley. The products in question: high-fructose corn syrup, a sweetener found in everything from Coca-Cola to cake; lysine, an amino acid used in feeding poultry and hogs; and citric acid, which adds tartness to jams and jellies, among many other uses. Some experts speculated that investigators are focusing on the possibility that ADM set predatory--meaning artificially low--prices on lysine, which Whitacre's BioProducts Division produces. That might help explain how ADM grabbed a 50% share of the worldwide market for lysine.

The probe put an uncomfortable spotlight on Andreas, 77, who for the past three decades has cultivated Presidents and putative Presidents by heaping money on them. According to Common Cause, Andreas, his wife and ADM have given a total of $1.4 million in so-called soft, or unrestricted, funds to the Republican Party since 1991, as well as $759,000 to the Democrats. In return for his largese, Andreas has often seemed to reap what he has sown. For example, ADM profits handsomely from federal programs that raise U.S. sugar prices above the world level, at an estimated cost to consumers of $1.4 billion a year. That creates a market for cheaper high-fructose corn syrup, which has all but replaced sugar as an ingredient in soft drinks. Such a sweet deal made the head of a Chicago commodities firm wonder last week: "If ADM owns the markets and laws, why would it need to fix prices?"

The 5-ft. 4-in. Andreas remained feisty throughout the week, privately telling friends that "no one is cowed or bowed" at ADM and publicly pledging the company's cooperation with the FBI. The scrutiny of ADM has prompted a sense of poetic justice in some members of the Chicago Board of Trade, as ADM helped FBI agents launch a 1989 sting that led to several commodities traders being convicted on fraud and racketeering. "There is a lot of snickering because ADM has finally got its ass caught in a sling," said a board member of the Board of Trade. "There is just this whole sweet irony of their getting stung after initiating a sting on us."

As for Whitacre, colleagues wondered last week why he would risk his shot at the top and a well-ordered life of small-town philanthropy--he gave $2,000 a year in college scholarships to graduating Moweaqua seniors--to spy on his own company. They were still wondering as Whitacre continued to report to work last week at his second-floor office in ADM headquarters.