COIMBATORE: A group of environmentalists and lawyers under the banner of Federation for Sustainable Development staged a demonstration here on Monday against the development of Bt brinjal varieties on the TNAU premises. The demonstrators shouted slogans just as Governor Surjit Singh Barnala was about to arrive at the university for its convocation ceremony, creating a flutter. The group, opposed to the genetically modified seeds, charged the TNAU with taking up research on Bt brinjal for commercial purpose, under the pressure of multinational firm Monsanto. Stating that Bt and GE crops would adversely affect the environment, the agitators asked the students not to accept the degree certificates during the convocation. The protestors were later dispersed by police.