August 1 (Reuters) - Canada's main stock index opened lower on Wednesday, pressured by escalating trade tensions and losses in energy shares after oil prices fell.
* At 9:30 a.m. ET (13:30 GMT), the Toronto Stock Exchange's S&P/TSX Composite index .GSPTSE was down 43.28 points, or 0.26 percent, at 16,390.73.