Lumia (citrus)
A recent genomic analysis of several species commonly called 'lemons' or 'limes' revealed that the various individual lumias have different genetic backgrounds. The 'Hybride Fourny' was found to be an F1 hybrid of a citron- pomelo cross, while the 'Jaffa lemon' was a more complex cross between the two species, perhaps an F2 hybrid. The Pomme d'Adam arose from a citron-micrantha cross, while two other lumias, the ‘Borneo’ and ‘Barum’ lemons, were found to be citron-pomelo-micrantha mixes.
Economic botany
Citrus has been a major commercial product in Florida since the 19th century. Florida produces over 70% of the U.S. citrus supply. The color of oranges is not related to ripening, but is a serious component for sales. The orange color only develops in areas with cool nighttime temperatures. In tropical climates, growers often expose the fruit to ethylene, to promote the loss of chlorophyll and expose the beta-carotenes (the orange color).