(Adds details, analyst's comment)
TORONTO, Feb 26 (Reuters) - The Toronto Stock Exchange's main index was lower on Tuesday morning, knocked down by profit-taking in the materials and energy sectors, which mirrored a decline in key commodity prices.
The index had risen in nine of the previous 12 trading days, led by commodities prices. But soft crude oil, spot gold and most base metals prices weighed on Tuesday.
Also, shares of Cott Corp (BCB.TO) shed 26 percent of their value after the soft-drink maker said a shelf-reduction move by Wal-Mart would have a "significant" impact on its business.
The resource-heavy S&P/TSX composite index .GSPTSE was down 62.91 points, or 0.46 percent, at 13,634.54. It rose more than 110 points on Monday.
The materials and energy sectors slid 1.1 percent and 0.5 percent, respectively.
Research In Motion RIM.TO, the BlackBerry maker, was the biggest weighted decliner, down C$2.75 at C$105.70.
Sal Masionis, stock broker at Brant Securities, said the TSX was also under pressure from data that showed U.S. producer prices jumped last month, stoking worries that inflation pressure might dissuade the U.S. Federal Reserve from chopping interest rates aggressively.
"The costs of anything you touch -- food, energy -- are way up so obviously this throws a bit of a monkey wrench into the market, which hates surprises," Masionis said.
Cott confirmed a report that retail giant Wal-Mart (WMT.N) has given it notice it would reduce the shelf space devoted to Cott's Sam's Choice soft drinks. For details, see: [nN26313169]
Cott's shares were down C$1.04, or 26 percent, at C$2.96.
On the upside, financial shares added 0.4 percent, with Canadian Imperial Bank of Commerce (CM.TO) rising 73 Canadian cents to C$68.83.
Later in the day, investors will eye Canada's federal budget for news on the capital gains tax or relief for Central Canada's beleaguered auto industry.
$1=$0.99 Canadian Reporting by Jonathan Spicer; Editing by Peter Galloway