Hindu: The global food crisis reached the U.S. on Wednesday as big retailers began rationing sales of rice in response to bulk purchases by customers alarmed by rocketing prices of staple foods. Wal-Mart’s cash and carry division, Sam’s Club, announced it would sell a maximum of four bags of rice a person to prevent supplies from running short. Its decision followed sporadic caps placed on purchases of rice and flour by some store managers at a rival bulk chain, Costco, in parts of …