(Adds details on specific stocks, updates prices)
* TSX down 15.51 points, or 0.1 percent, at 16,144.16
* Six of the TSX's 10 main groups move lower
TORONTO, Dec 21 (Reuters) - Canada's main stock index was slightly lower in morning trade on Thursday, with natural resource stocks weighing and BlackBerry pulling back after a sharp jump, while rising banks limited the overall fall.
* At 9:55 a.m. ET (1455 GMT), the Toronto Stock Exchange's S&P/TSX composite index was down 15.51 points, or 0.1 percent, to 16,144.16.
* Six of its 10 main groups lost ground, with decliners outnumbering advancers by a 1.6-to-1 ratio.
* The energy group retreated 0.3 percent as the country's producers struggle to get their product to market, with pipeline operator Enbridge Inc down 0.8 percent to C$49.025.
* The materials group, which includes precious and base metals miners and fertilizer companies, lost 0.4 percent.
* BlackBerry Ltd fell 2.1 percent to C$15.27 a day after surging on the back of its quarterly earnings.
* The financials group gained 0.3 percent, as bonds yields rose after strong inflation and retail sales data.
* Cogeco Communications Inc rose 4 percent to C$90.53 and Dream Office Real Estate Investment Trust declined 3.3 percent to C$21.74 after TD Securities upgraded Cogeco and downgraded Dream Office.
* Cable and telecom company Quebecor Inc rose 1.9 percent to C$23.94 after Desjardins raised it to a "buy".
* Paramount Resources Ltd rose 4 percent to C$18.83 after announcing a share buyback plan. (Reporting by Alastair Sharp; Editing by David Gregorio)