The market share and the Herfindahl-Hirschman Index (HHI) werecalculated for the potential market of registered rice varieties from January 01, 1998 until July 05, 2012 and real market (rice varieties adopted by farmers). There are national and international companies on the Brazilian rice seed market. Among the national companies, there are public and private companies. In total, 254 rice varieties registered in Brazil by July 05, 2012
