Citrus is the most consumed fruit in the world.China is not only a large citrus growing country but also a large citrus consuming and exporting country.With a total growing area of 1.91 million hectares and an annual production of 20.59 million tons,China took the first place among the world citrus growing countries in 2007.Currently,citrus are cultivated in 20 provinces(municipalities or autonomous regions) in China.Citrus growing is the main source of income for farmers in mountainous areas of sou...