UPDATE 2-Toronto stocks turn lower, oil offsets materials
* Oil and gas sector turns negative after initial charge
* Gold miners shine, subindex up 4.3 percent
* RBC cuts share-price targets on five banks, Manulife
TORONTO, Oct 7 (Reuters) - The Toronto Stock Exchange's main index was lower on Tuesday morning, after soaring at the open, as strength in gold miners and other materials shares was not enough to offset weakness in oil companies.
The index jumped nearly 300 points shortly after market open, turned negative, then kept swinging erratically in nervous dealings.
The oil and gas sector led the initial charge higher, as oil prices CLc1 rose from the eight-month lows hit on Monday but then fell back below $90 a barrel. The index's energy group, which was battered in the previous session, was up more than 10 percent at the open but swiftly cut gains.
Canadian Natural Resources CNQ.TO rose 0.2 percent to C$58.48, but Suncor SU.TO was down 4.6 percent at C$30.06.
Shortly after 11:15 a.m. (1515 GMT), the S&P/TSX composite index .GSPTSE was down 60.40 points, or 0.59 percent, at 10,170.03. Eight of the index's 10 main groups were in negative territory. Continued...