(Updates prices, adds sector details) April 8 (Reuters) - Canada’s main stock index opened higher on Thursday as investors bet on a faster global economic rebound, while a jump in gold and copper prices helped mining stocks. The materials sector, which includes precious and base metals miners and fertilizer companies, added 1.3% as gold futures rose 0.5% to $1,748.7 an ounce to hit a three-week peak. * At 9:37 a.m. ET (13:37 GMT), the Toronto Stock Exchange’s S&P/TSX composite index was up 8.37 points, or 0.04%, at 19,137.44. * Canada’s Canopy Growth Corp said on Thursday it will buy rival Supreme Cannabis Co Inc for C$323.3 million ($256.85 million), as the world’s biggest cannabis producer bolsters its portfolio to tap surging demand. * The energy sector dropped 1.1% as U.S. crude prices were down 0.9% a barrel, while Brent crude lost 0.6%. * The financials sector slipped 0.7%. The industrials sector fell 0.2%. * On the TSX, 119 issues were higher, while 99 issues declined for a 1.20-to-1 ratio favouring gainers, with 12.09 million shares traded. * The largest percentage gainers on the TSX were Osisko Mining Inc, which jumped 4.8% and Endeavour Silver , which rose 4.5%. * Air Canada fell 2.3%, the most on the TSX, while the second-biggest decliner was Vermilion Energy, down 2.3%. * The most heavily traded shares by volume were Supreme Cannabis Co, up 52.8%, Bombardier, down 2%, and Suncor Energy, down 1.3%. * The TSX posted nine new 52-week highs and no new lows. * Across all Canadian issues, there were 84 new 52-week highs and five new lows, with total volume of 48.34 million shares.