* TSX ends down 133.18 points at 12,602.23
* Main index touches 5-week low during session
* Strong U.S. dollar drags down oil, metals prices
* Materials, energy groups lead retreat
* Nine of 10 main sectors lower (Adds details, quote)
By Jennifer Kwan
TORONTO, Nov 16 (Reuters) - Toronto's main stock index fell to its lowest in five weeks on Tuesday before recovering some ground as global economic woes boosted the U.S. dollar, weighing on commodity prices and the hefty resource sectors.
A strong U.S. dollar, lifted in part by concerns about sovereign debt problems in Ireland and other European economies, helped drag oil prices down more than 3 percent to below $83 a barrel as investors cut their exposure to commodities. [O/R]
Canadian Natural Resources CNQ.TO fell 2.2 percent to C$38.70, while Suncor Energy SU.TO retreated 2.2 percent at C$33.67. TransCanada Corp TRP.TO sank 2.6 percent to C$36.00.
The three big energy companies were the most influential movers on the downside. The broader energy group was down 1.8 percent.
"The market has become somewhat jittery that what happened to Greece might happen to Ireland, too. The market is basically telling us we don't like these uncertainties," said Sid Mokhtari, director of institutional equity research at CIBC World Markets in Toronto.
In May, Greece agreed to implement economic policy changes in exchange in emergency funding to avoid default. [ID:nLDE69B1I0]
The Toronto Stock Exchange's S&P/TSX composite index .GSPTSE finished the day down 133.18 points, or 1.05 percent, at 12,602.23. Nine of the index's 10 main groups were lower, with telecoms the lone sector in the black. It was up 0.5 percent.
The main index slid to a low of 12,501.82, its weakest since mid-October and near its 50-day moving average, a key technical level that, if breached, could signal further losses, said Mokhtari.
"From a technical perspective the level of overbought conditions of the market was at elevated readings. We were overbought," he said.
In addition to the worries about euro zone debt, investor sentiment soured on worries that China might further tighten monetary policy to control inflation, a move that could hurt the global economic recovery. [ID:nL3E6MG081] [MKTS/GLOB]
In the United States, core producer prices recorded their largest drop in more than four years in October and industrial output was little changed. The PPI reading underscored concerns at the Federal Reserve that low inflation could spiral into a damaging bout of deflation, analysts said. [ID:nN16103144]
Telecommunications stocks rose, with BCE Inc BCE.TO up 0.8 percent to C$33.34, and Telus Corp T.TO up 1.5 percent at C$45.74.
The blue chip S&P/TSX 60 index .TSE60 closed 7.10 points lower, or 0.97 percent, at 723.14.
The materials group, home to mining and fertilizer companies, was down 1.6 percent. Cameco Corp CCO.TO, slumped 4.5 percent to C$34.30, while Teck Resources TCKb.TO was off 2.4 percent at C$48.16. NovaGold Resources Inc NG.TO tumbled 3.6 percent to C$13.76.
Copper prices skidded 5 percent on euro zone jitters and China tightening fears, while gold tumbled on a rallying greenback. [MET/L] [GOL/]
In company news, Nexen Inc NXY.TO sank 3.7 percent to C$21.55 after it said output at its C$6.1 billion Long Lake oil sands project will remain below its design rate through 2011 as the company works the bugs out of the project. [ID:nN16114618]
($1=$1.02 Canadian) (Editing by Frank McGurty)