* TSX falls 145.47 points, or 1.20 percent, to 11,974.05 * Nine of 10 main index sectors decline * First Quantum sheds 8.7 percent, erasing Tuesday's gains By John Tilak TORONTO, April 17 (Reuters) - Canada's main stock index fell more than 1 percent on Wednesday with almost every major sector declining as worries mounted about global economic growth and weak U.S. earnings reports. Oil prices also tumbled on demand concerns, and weighed on oil and gas shares. Investors were disappointed by U.S. quarterly reports from companies such as Bank of America Corp and Yahoo Inc and by a cut in global economic growth forecasts by the International Monetary Fund. The Bank of Canada chopped its economic growth forecast for the country and left interest rates unchanged, but still insisted its next rate move would likely be a hike. Toronto stocks are down about 4 percent this year as weak commodity prices have weighed on resource shares, which make up about 40 percent of the index. "We're certainly in some form of correction," said Michael Sprung, president of Sprung Investment Management. "The market was ahead of itself, and we're taking a definite setback." "The overall recovery is quite fragile. We're likely to see very low GDP growth for the foreseeable future." The Toronto Stock Exchange's S&P/TSX composite index was down 145.47 points, or 1.20 percent, at 11,974.05 in midmorning trade. Nine of the 10 main sectors on the index were in the red. Energy shares declined the most, slipping 1.8 percent. The materials sector gave back 1.1 percent, mainly due to a 5.3 percent decline in mining stocks. Miner First Quantum Minerals Ltd shed 8.7 percent to C$15.55, erasing almost all the gains it made the previous day. It played the biggest role of any single stock in leading the index lower. Financials, the index's most heavily weighted sector, lost 0.7 percent.