Cotton farmers have earned an additional income of Rs 7,039 crore [1.27 bill EUR / 1.75 bill USD] in 2006 after a 50% increase in yield due to use of Bt cotton seed, a study conducted jointly by the Associated Chamber of Commerce & Industry (Assocham) and IMRB International has revealed. [...] Another study conducted by Assocham in collaboration with Indicus Analytics found are under Bt cotton increased to over 8 million acres with 2 million farmers cultivating it.