Petrochemicals stocks led the Saudi bourse lower after concerns that Europe's debt woes will curb energy demand growth drag down oil prices to three-month lows. The Saudi stock market benchmark Tadawul All-Share Index (TASI) declined 2.28 percent to 6,539.36 points after the heavyweight petrochemicals index shed 4.4 percent. Accounting for almost a third of the day's traded turnover, petrochemical giants Saudi Basic Industries Corp (SABIC) and its affiliate Kayan shed respectively 5.1 and 5.7 percent. Of 138 listed firms, 125 ended lower while insurance stocks dominated gaining stocks. US oil futures dropped for a fourth straight session to a three