The biggest drag on the market was integrated energy company Suncor Energy Inc (>> Suncor Energy Inc.), which fell 2.3 percent to C$31.07. Other big energy losses included TransCanada Corp's (>> TransCanada Corporation), 1.5 percent fall to C$46.12.

Nine of the 10 main subgroups of the TSX index ended the day down.

The wide selloff was sparked by the Bank of Japan, which did not to take any fresh measures on Tuesday to tackle rising government bond yields, which threaten to thwart its $1.4 trillion stimulus program.

That announcement followed recent remarks by U.S. Federal Reserve Chairman Ben Bernanke that signaled a possible slowdown in the Fed's asset-buying program in the coming months.

"The selloff today is a reflection of concerns around reducing monetary policy stimulus around the world," said Craig Fehr, Canadian market strategist at Missouri-based investment firm Edward Jones. "It's more about rhetoric than action, there isn't a tremendous amount of economic data. We're just seeing knee-jerk reactions from the market."

The Toronto Stock Exchange's S&P/TSX composite index <.GSPTSE> ended the day down 159.10 points, or 1.28 percent, at 12,223.57.

The decline was mirrored by equity markets globally, along with falls in the price of commodities and the value of the U.S. dollar.

The TSX index's materials group was hit by weakness in the gold sector. Barrick Gold Corp (>> Barrick Gold Corp.) dropped 3.9 percent to C$19.99, and Goldcorp Inc (>> Goldcorp Inc.) fell 3.1 percent to C$28.27.

Kinross Gold Corp (>> Kinross Gold Corporation) was down 6.4 percent at C$6.03 after the company announced it had halted development at a gold project in Ecuador.

Shares in financial firms also swooned in the wake of the Bank of Japan announcement, with shares in the Royal Bank of Canada (>> Royal Bank of Canada) showing the biggest drop, 1.2 percent, to C$59.42. Toronto-Dominion Bank (>> Toronto-Dominion Bank) lost nearly 1 percent to close at C$81.67, while Bank of Nova Scotia (>> The Bank of Nova Scotia) lost 0.9 percent to C$56.86.

Yogawear maker Lululemon Athletica Inc (>> Lululemon Athletica Inc) fell more than 17.6 percent after saying its chief executive was stepping down. It closed at C$69.22.

One bright spot was Catamaran Corp (>> Centenario Copper), a pharmacy benefits manager. Shares in the company surged more than 10 percent to C$54.91 after major U.S. health insurer Cigna Corp (>> CIGNA Corporation) said the pair had signed a 10-year agreement.

($1=$1.02 Canadian)

(Editing by Jeffrey Hodgson; and Peter Galloway)

By Peter N Henderson