ALLIACEA PRODUCTION SYSTEMS IN THE IBERIAN PENINSULA: FACTS AND FIGURES OF POTENTIAL INTEREST FOR A WORLDWIDE R & D NETWORK
As a commodity for internal and international trade, onion is a traditional crop in the Valencia district due to the mild weather conditions, medium and fine textured soils, and a strong tradition with the farmers. Usually, Valencia represents 25–30% of the total national area for the crop, and 30–40% of total production. Although area and production declined in recent years, Valencia has been the basis of international trade with more than 11 000 tons exported in 1888 and more than 100 000 tons in 1903. In 1940, Valencia was responsible for 95–98% of Spanish exports.
Total exports are still heavily weighted by Valencian onion varieties, whose cultivation has spread across Spain due to high yields and bulb quality for which selection has been exercised for more than 500 years.