Tamilnad Mercantile Bank has increased the base rate (BR) and prime lending rate (PLR) by 50 basis points with effect from January 1. The bank has revised the base rate from 9 per cent to 9.50 per cent and prime lending rate from 14.50 per cent to 15 per cent. S. Selvan Rajadurai, General Manager, Business Development of the bank said in a statement here on Thursday. — Staff Reporter