CANADA STOCKS-TSX turns negative as resource stocks drag

TORONTO Jan 9 (Reuters) - Canada's main stock index turned negative on Wednesday, as investor caution and weakness among resource stocks offset earnings optimism following Alcoa Inc's outlook and a rise in TransCanada Corp shares after the company won a large contract.

The Toronto Stock Exchange's S&P/TSX composite index was down 0.49 of a point at 12,504.32. Five of the index's 10 main groups were in negative territory.