* TSX rises 61.39 points to 8,690.49
* Energy and gold-mining stocks surge
* Eighth straight higher close for index (Adds details, comments and official numbers)
By Frank Pingue
TORONTO, March 19 (Reuters) - Toronto's main stock index closed higher for an eighth straight session on Thursday as the U.S. Federal Reserve's plan to fight the recession boosted commodity prices and buoyed the resource-heavy index.
Energy and gold-mining companies headlined the rally, which was largely a continuation from Wednesday's surge after the Fed unexpectedly said it would buy long-term Treasury bonds in a bid to revive the recession-hit economy.
The key Toronto index is now up 16 percent from the five-year low hit two weeks ago and finished the session at its highest closing level since Feb. 11. It was also the first time since December 2004 that the TSX has risen in eight straight sessions.
"We were so oversold that any rebound would expect to be a pretty strong one," said Gavin Graham, director of Investments at BMO Asset Management.
"What's been impressive is the way that this continued, and unlike in the (United) States where you have had a couple down days, we haven't had that. We've seen the market keep going."
The S&P/TSX composite index .GSPTSE rose 61.39 points, or 0.71 percent, to 8,690.49. The index shot 2.5 percent higher right after the open but by midday had relinquished much of that gain, spending the afternoon in a fairly tight range.
$1=$1.24 Canadian Editing by Peter Galloway