India has overtaken the US to become the second largest cotton producing country in the world, after China, a study by International Service For the Acquisition of Agri-biotech Application(ISAAA) said. India, which was having one of the lowest cotton yields in the world, has become a net cotton exporter, potentially five million bales in 2007-08, the study said. Bt cton was a major factor contributing to higher rate of production from 15.8 million bales in 2001-02 to31millionbalesin2007-08,itsaid.