CANADA STOCKS-TSX volatile as crude whips energy stocks

(Adds analyst comment, details, market reactions)

* TSX down 46.43 points, or 0.34 percent at 13,435.47

* Six of the TSX’s 10 main groups were up

TORONTO, Sept 2 (Reuters) - Canada’s main stock index seesawed on Wednesday in extremely choppy trading as energy stocks beset by volatile crude oil prices capped gains in other sectors.

The index gyrated between positive and negative territory throughout the morning after initially rallying more than 1 percent on China’s latest effort to soothe investors’ anxiety. Markets are concerned about the country’s slowing growth and what that means for the global economy.

“Volatility continues to rule the day, both to the upside and the downside,” said Craig Fehr, Canadian market strategist at Edward Jones in St. Louis. ” ... It partly reflects markets trying to digest what the bigger trend is in China.”

“On-the-fly” policy reactions out of Beijing are contributing to the dramatic daily swings, Fehr added.

The focus on China, the fluctuation in commodity prices and uncertainty around the U.S. Federal Reserve’s decision on interest rates will keep markets on edge, he said.

Fundamentals, including growth in Canada, the United States and Europe were bright spots, however.

“As we look out a little bit further, I think the backdrop is set for equity markets ... to inch higher,” Fehr said.

At 12:06 p.m. EDT (1606 GMT), the Toronto Stock Exchange’s S&P/TSX composite index was down 46.43 points, or 0.34 percent, at 13,435.47 after touching a session high of 13,553.31.

Of the index’s 10 main groups, six were positive.

But energy stocks gave up 2.2 percent, hurt by U.S. crude prices that swung between gains of 2 percent and losses of nearly 4 percent.

Seventeen of the top 20 biggest drags on the index were oil and gas companies. Suncor Energy Inc fell 1.8 percent to C$35.11, followed by Canadian Natural Resources, which declined 1.6 percent to C$27.90. MEG Energy Corp plunged 9.7 percent to C$9.65.

Materials, home to mining companies, retreated 0.4 percent.

Offsetting declines was a 1.9 percent advance to C$301.81 by the influential Valeant Pharmaceuticals International Inc . The overall healthcare group was up 3.6 percent.

Alimentation Couche-Tard, which reported robust U.S. growth on Tuesday, rallied 4.1 percent to C$59.04.

Fehr said the market’s recent declines made for a good buying opportunity for investors, but those eyeing energy or materials stocks needed to be patient.

Declining issues outnumbered advancing ones on the TSX by 163 to 80, for a 2.04-to-1 ratio on the downside. (Reporting by Solarina Ho; Editing by Lisa Von Ahn)