Looking to build on its dominant position in the U.S. fertilizer business, IMC Global Inc. plans to acquire competitor Freeport-McMoRan Inc. for about $800 million in stock. "This merger will represent a major step in IMC Global's growth strategy and reaffirms our commitment to being the world's leading, low-cost supplier of agricultural products and services," said Robert E. Fowler Jr., president and chief executive of IMC. While competitors, the two companies are well-acquainted with each other. IMC and Freeport-McMoRan have been partners in a fertilizer-producing venture since 1993. Terms of the deal call for IMC Global, based in Northbrook, Ill., to issue 0.9 share of its own stock for each share of Freeport, as well as a warrant granting the right to buy one-third of a share of IMC at a price equal to $44.50 a share up to three years after the merger. Shares of New Orleans-based Freeport-McMoRan gained $4.63 to close at $31.19 on the New York Stock Exchange. IMC shares lost 63 cents to close at $33.13.