NEW YORK — Irene Rosenfeld, chairman and chief executive officer of Kraft Foods Inc., has moved up to No. 1 in Fortune magazine’s annual ranking of America’s leading businesswomen. Ms. Rosenfeld, who ranked No. 2 in 2010, displaced Indra Nooyi, chairman and c.e.o. of PepsiCo, Inc., who fell to No. 2. “Rosenfeld made a big show of power this year with her decision to split Kraft into two companies, a reversal of her previous strategy of expanding through acquisitions (like the 2010 purchase of Cadbury),” Fortune said. “Her new role hasn’t been decided but she plans to remain c.e.o. until the deal’s expected close in 2012.” Patricia Woertz, chairman, c.e.o. and president of Archer Daniels Midland Co., maintained her position at No. 3. Jan Fields, president of McDonald’s USA, moved up to No. 17 from No. 25 in 2010, while Denise Morrison, c.e.o. and president of Campbell Soup Co., and Ilene Gordon, chairman, c.e.o. and president of Corn Products International, Inc., moved into the rankings for the first time at Nos. 21 and 42, respectively.