(Adds strategist comment, update prices to close)
* TSX ends down 71.28 points, or 0.51 percent, to 13,791.88
* Six of the TSX's 10 main groups fall
By Alastair Sharp and John Tilak
TORONTO, Oct 29 (Reuters) - Canada's main stock index fell on Thursday, with sliding commodity prices hurting miners, while Bombardier Inc plunged after reporting a massive quarterly loss and Potash Corp fell on trimmed earnings and sales forecasts.
The losses were offset by gains in the heavyweight energy sector amid volatile oil market trade.
Bombardier shed 15.5 percent to C$1.36 after the Montreal-based plane and train maker said the Quebec government will invest $1 billion in its long-delayed CSeries jet program and announced a $4.6 billion third-quarter loss.
The decline came a day after the market jumped following the U.S. Federal Reserve's decision to hold interest rates steady.
"It was a consolidation day," said Colin Cieszynski, chief market strategist at CMC Markets. "The Street was basically digesting the big moves yesterday," he said, adding that investors are coming around to the reality of an eventual Fed hike.
The Toronto Stock Exchange's S&P/TSX composite index ended down 71.28 points, or 0.51 percent, at 13,791.88.
There were 135 declining issues versus 101 gainers.
Goldcorp Inc lost 10.2 percent to C$17.32 as the price of gold fell for a second day, reaching its lowest level in three weeks.
Potash Corp fell 3 percent to C$27.32 after the world's biggest fertilizer company by capacity said it was cutting production as economic pressures weigh on demand for potash, a crop nutrient.
First Quantum Minerals Ltd shed 10.7 percent to C$6.66.
Copper prices hit a three-week low, hurt by data pointing to weaker U.S. economic growth.
On the positive side, Suncor Energy Inc gained 3.4 percent to C$38.81 and Cenovus Energy added 2.8 percent to C$19.78, while the overall energy group rose 0.6 percent.
U.S. crude prices were up 1.4 percent to $46.56 a barrel, while Brent added 0.3 percent to $49.20.
The financial sector slipped 0.4 percent, with insurer Manulife Financial off 1.5 percent at C$22.23 and Bank of Montreal slipping 1 percent to C$76.93. (Reporting by Alastair Sharp; Editing by Dan Grebler)