Most actively traded companies on the TSX, TSX Venture Exchange markets

TORONTO - Some of the most active companies traded Wednesday on the Toronto Stock Exchange and the TSX Venture Exchange:

Toronto Stock Exchange (12,486.64 down 95.11 points):

Potash Corp. of Saskatchewan (TSX:POT). Fertilizer producer. Down $2.86, or 8.76 per cent, at $29.80 on 13.72 million shares. The fertilizer giant's stock continued to slide a day after a Russian rival OAO Uralkali announced it will stop its export sales through the Belarusian Potash Company and direct all export volumes through its own Uralkali Trading. The move will weaken the price of the mineral and potentially impact Saskatchewan's economy.

Bombardier Inc. (TSX:BBD.B). Transportation equipment. Down 17 cents, or 3.31 per cent, at $4.96 on 12.14 million shares.

Connacher Oil and Gas Ltd. (TSX:CLL). Oil and gas. Up four cents, or 17.39 per cent, at 27 cents on 7.58 million shares.

TORC Oil and Gas Ltd. (TSX:TOG). Oil and gas. Up three cents, or 2.01 per cent, at $1.52 on 7.41 million shares.

Barrick Gold Corp. (TSX:ABX). Miner. Down 72 cents, or 4.06 per cent, at $17 on 5.37 million shares. The world's biggest gold miner is reporting its second-quarter results Thursday. Analysts are expecting earnings of 56 cents US per share on average and revenue of $3.14 billion.

Toronto Venture Exchange (917.34 up 2.94 points):

Border Petroleum Corp. (TSXV:BOR). Oil and gas. Down half a cent, or 25 per cent, at 1.5 cents on 8.48 million shares.

Alberta Oilsands Inc. (TSXV:AOS). Oilsands explorer. Down three cents, or 17.65 per cent, at 14 cents on 5.75 million shares.

Company reporting major news:

Canadian Natural Resources Ltd. (TSX:CNQ). Oil and gas. Up 17 cents, or 0.54 per cent, at $31.83 on 3.11 million shares. The Calgary-based company says that damage at its oilsands project in northeastern Alberta has been contained and the cleanup is proceeding well. Canadian Natural blames a "mechanical failure" at an old well behind the ongoing bitumen seepage at its oilsands project on the Cold Lake Air Weapons Range.

CGI Group (TSX:GIB.A). Information technology. Up $3.17, or 9.81 per cent, at $35.50 on 3.15 million shares. Shares closed at its highest level after the company announced it's looking for potential U.S. acquisitions and reported solid second-quarter results. Net profit more than doubled to $178.2 million while revenue soared 141 per cent.

RioCan Real Estate Investment Trust (TSX:REI.UN). Retail real estate. Down 21 cents, or 0.86 per cent, at $24.34 on 772,723 shares. Second-quarter net earnings attributable to unitholders fell nearly 65 per cent due to adjustments to the fair value of its holdings. The weaker results were also due to the vacancies of nine Zellers locations, but the trust says it is on its way to replacing the lost rental income.

Torstar Corp. (TSX:TS.B). Publisher. Down 30 cents, or 5.04 per cent, at $5.65 on 124,345 shares. Second-quarter profits dropped 44 per cent as newspaper revenues declined and sales at its Harlequin book publishing operations slumped on a slowdown overseas. The results fell short of analyst expectations. Revenue slipped 7.5 per cent to $354.9 million.