UPDATE 3-Wal-Mart's Sam's Club limits rice purchases

On Tuesday, Tim Johnson, president-CEO of California Rice Commission, which represents growers and millers of rice in the state, said: "Bottom line, there is no rice shortage in the United States. We have supplies."

Wal-Mart shares were up 0.4 percent to $56.80 in afternoon trading, while Costco shares rose 1.7 percent to $69.26. (Reporting by Nicole Maestri, editing by Jeffrey Benkoe and Tim Dobbyn)