May 19 (Reuters) - Wall Street’s main indexes opened lower on Wednesday on fears that rising inflation could force the U.S. Federal Reserve to pare back its support soon. The Dow Jones Industrial Average fell 114.9 points, or 0.34%, at the open to 33945.81. The S&P 500 dropped 29.4 points, or 0.71%, at the open to 4098.45, while the Nasdaq Composite was down 225.5 points, or 1.69%, to 13078.186 at the opening bell. (Reporting by Shashank Nayar in Bengaluru; Editing by Maju Samuel) Our Standards: The Thomson Reuters Trust Principles.