The Sweet Orange (Citrus sinensis, Rutaceae) is an ancient hybrid between pomelo (C. maxima) and tangerine (C. reticulata). Orange fruits are widely grown in warm climates worldwide, and commonly eaten fresh, or squeezed for their juice. Orange trees are widely cultivated in tropical and subtropical climates.
The Orange section is part of the Fruit Crop Category of Pomology.org and currently contains 59 resources. One of the most popular entries is an article on “Partial Purification of a Growth Factor from Orange Juice Which Affects Citrus Tissue Culture and Its Replacement by Citric Acid” which was published in the science journal “Plant Physiology” in 1975.
The authors conclude that citric acid as a natural component of citrus juice is responsible for the growth-promoting activity of orange juice. The growth-promoting activity of juice involves both cell division and cell enlargement. Another popular article from the same journal covers “Endogenous Abscisic Acid in Relation to Bud Growth in Alternate Bearing ‘Valencia’ Orange”.
