(fxcue news) - After nine successive days of gains, the Canadian market turned weak on Monday, as stocks, particularly in the technology sector, tumbled on sustained selling pressure. Energy and materials stocks fell on weak commodity prices. Tech stocks declined amid concerns about the impact of China's low-cost startup DeepSeek's emergence as a powerful AI model. The mood was cautious with investors awaiting monetary policy announcements from the Bank of Canada, the Federal Reserve and the European Central Bank this week. The benchmark S&P/TSX Composite Index, which opened with a big negative gap at 25,347.93 and slid to 25,204.06 subsequently, ended the session with a loss of 179.34 points or 0.7% at 25,289.15. The Information Technology Index slid 3.44%. Celestica tanked 28%. Celestica is deeply invested in AI for various applications, including energy delivery, as well offering products that are used in major energy-consumer data centers. Bitfarms (BITF.TO) plunged 13.7%, while Converge Technology Solutions (CTS.TO), Dye & Durham (DND.TO), Lightspeed Commerce (LSPD.TO), Descartes Systems Group (DSG.TO), BlackBerry (BB.TO) and Kinaxis Inc (KXS.TO) lost 1 to 4%. Energy stocks Enerflex (EFX.TO) and Terravest Capital (TVK.TO) ended lower by 7.6% and 6.8%, respectively. Arc Resources (ARX.TO), Tourmaline Oil Corp (TOU.TO), Precision Drilling Corporation (PD.TO), Topaz Energy (TPZ.TO) and Vermilion Energy (VET.TO) lost 1.7 to 4%. Among materials shares, First Majestic Silver (AG.TO), Aya Gold & Silver (AYA.TO), Iamgold Corp (IMG.TO), Ssr Mining (SSRM.TO), Ivanhoe Mines (IVN.TO), MAG Silver Corp (MAG.TO), Ero Copper (ERO.TO), Silvercrest Metals (SIL.TO), Seabridge Gold (SEA.TO) and First Quantum Minerals (FM.TO) lost 4 to 6%. Telus Corp (T.TO), BCE Inc (BCE.TO), Riocan REIT (REI.UN.TO), Colliers International (CIGI.TO), TFI International (TFII.TO) and GFL Environmental (GFL.TO) moved higher, gaining 1.3 to 4%. In economic news, wholesale sales in Canada increased by 0.1% month-over-month in December after a 0.2% decline in November, according to preliminary estimates.