The orange is the fruit of the citrus species. Originating in Southeast Asia, oranges already were cultivated in China as far back as 2500 BC. Between the late fifteenth century and the beginnings of the sixteenth century, Italian and Portuguese merchants brought orange trees in the Mediterranean area. The Spanish introduced the sweet orange to the American continent in the mid-1500s. Orange trees are widely grown in tropical and subtropical climates for their sweet fruit, which can be eaten fresh or processed to obtain juice, and for the fragrant peel. They have been the most cultivated tree fruit in the world since 1987 and sweet oranges account for approximately 70% of the citrus production. In 2010, 68.3 million tonnes of oranges were grown worldwide, particularly in Brazil and in the US states of California and Florida.