CANADA STOCKS-TSX falls as drop in commodity prices pressures resource shares

TORONTO, March 7 (Reuters) - Canada's main stock index fell on Wednesday as a drop in commodity prices weighed on resource shares, while steel producer Stelco Holdings Inc rallied on prospects for Canada to be exempted from proposed U.S. metals tariffs.

The Toronto Stock Exchange's S&P/TSX composite index unofficially closed down 72.58 points, or 0.47 percent, at 15,472.61. Eight of the index's 10 main groups ended lower. (Reporting by Fergal Smith; editing by Diane Craft)