India, Aug. 21 -- Sugar prices have turned bitter as they are rising rapidly across the country, driven by speculation over record-low stocks and the approaching festive season. This prompted the Government to impose a stock limit on sugar for bulk consumers, including confectionery makers, soft drink manufacturers, food processing industries, sweetmeat sellers and other institutional buyers. Retail prices have risen by approximately 20 per cent since August 7 across major cities. The retail price of sugar has increased from '52 to around '62 over the past 12 days, representing a rise of 19-21 per cent. The all-India average ex-mill price rose to '5,400-5,500 a quintal on Tuesday, up from '3,900 a year earlier. Union Food Minister Pralhad...