Consensus documents contain information for use during the regulatory assessment of a particular product. This Consensus Document addresses the biology of rice (Oryza sativa). It contains a general description of rice as a crop plant, its taxonomy, centre of origin/diversity, identification methods, reproductive biology, crosses and ecology. However, its ecology in regard to specific geographic regions is not presented, since this will vary. For intraspecific and interspecific crosses, emphasis has been placed on detailing potential hybridisation between the cultivated species and their close relatives. Emphasis has also been placed on the recent contributions of biotechnology to knowledge of rice biology, including identification and transformation methods. These reflect progress in biotechnology, particularly with respect to rice among monocot crop plants.