Whitman Corporation (NYSE: WH) and PepsiAmericas (NYSE: PAS), the second and third largest U.S. based Pepsi Bottlers, today announced plans to merge later this year.Under an agreement approved by the companies' boards of directors, PepsiAmericas will become a wholly-owned subsidiary of Whitman. The merger is intended to make Whitman a larger, stronger, and more competitive bottler, with annual sales of approximately $3.