(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 .GSPTSE 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 BB.TO 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 CCA.TO rose 4 percent to C$90.53 and Dream Office Real Estate Investment Trust D_u.TO declined 3.3 percent to C$21.74 after TD Securities upgraded Cogeco and downgraded Dream Office.
* Cable and telecom company Quebecor Inc QBRb.TO rose 1.9 percent to C$23.94 after Desjardins raised it to a "buy".
* Paramount Resources Ltd POU.TO rose 4 percent to C$18.83 after announcing a share buyback plan.