TORONTO, July 6 (Reuters) - Toronto's main stock index fell early on Friday, led by energy and mining shares, in the wake of tepid jobs data in Canada and the United States and after the head of the International Monetary Fund expressed concern about the global economy. The Toronto Stock Exchange's S&P/TSX composite index was down 85.35 points, or 0.7 percent, at 11,731.68 shortly after the open.