Kolkata, March 27 : The defeat in the recent bypoll to the Sagardighi Assembly constituency in Murshidabad district, which hinted at substantial erosion of a dedicated vote-bank in the minority-dominated erstwhile Trinamool Congress stronghold, has prompted Chief Minister Mamata Banerjee to replace the minister in charge of minority affairs and madrasa education and take charge of the same herself. The decision to remove Ghulam Rabbani as the minority affairs minister was announced on Monday, when it was also said that the affairs of the department will now be under the purview of the Chief Minister. Rabbani has been transferred to the horticulture department. The current minister of state in charge of MSMEs and textiles department, Chandranath Sinha, has been given the additional charge of minister of state for minority affairs and madrasa education. In the Sagardighi bypoll, Left Front supported Congress candidate Bayron Biswas had defeated Trinamool's Debashis Banerjee by a margin of 22,980 votes. The result came as a shocker for Trinamool, as Sagardighi -- a minority-dominated constituency -- was a traditional stronghold of the ruling party, where it won by big margins since 2011. Recently, Trinamool had also reshuffled the party's minority cell. Now the Chief Minister herself taking charge of the minority affairs and madrasa education department becomes significant in West Bengal's evolving political situation. /IANS