The key Indian equity indices traded on a positive note on Tuesday morning, with the BSE Sensex surging over 300 points. Healthy buying was witnessed in banking and finance stocks. Further, gains in the Asian markets also supported the domestic indices, analysts said. Sensex was trading at 37,270.13, higher by 330.53 points or 0.89 per cent from the previous close of 36,939.60. It opened at 37,092.86 and has so far ...