(Adds fund manager's comment, details, and updates prices)
* TSX down 79.84 points, or 0.52 percent, at 15,306.93
* All 10 main index sectors lower
By Alastair Sharp
TORONTO, April 17 (Reuters) - Canada's main stock index was broadly lower on Friday as heavyweight oil and gas shares retreated on a drop in oil prices, while banks also took a hit.
Crude prices came under pressure from signs that supply is still growing, and the benchmark index's energy group retreated 0.4 percent.
In the group, Suncor Energy Inc fell 0.4 percent to C$39.92, and pipeline company Enbridge Inc declined 0.5 percent to C$64.08.
Oil has bounced off March lows below $45 a barrel but is still far cheaper than it was a year ago.
At 10:19 a.m. EDT (1419 GMT), the Toronto Stock Exchange's S&P/TSX composite index was off 79.84 points, or 0.52 percent, at 15,306.93. It hit its lowest level of the week earlier in the session, and looked on track for a 0.5 percent weekly loss. All 10 main index sectors were lower.
"Markets had a nice run here," said Irwin Michael, portfolio manager at ABC Funds. "Hopefully we don't have the 'sell in May, go away' concern."
The biggest weights on the index included Royal Bank of Canada, which fell 0.8 percent to C$80.57, and Toronto-Dominion Bank, which declined 0.7 percent to C$55.63.
The overall financials group retreated 0.6 percent after a recent rise.
The most influential gainers included Barrick Gold Corp , which rose 1.8 percent to C$15.66, and Goldcorp Inc , which advanced 0.8 percent to C$24.34.
$1=$1.22 Canadian Editing by Chizu Nomiyama; and Peter Galloway