Oranges, Lemons and Grapefruits
During tours — yes, the citrus station does draw in the curious — visitors learn that lemons weren't always small and cute. Long before grocers began stocking the fist-sized variety popular today, citrus growers fumbled with its ancestor, a lumpy 5-pound fruit the size of a Nerf football.It's a reminder that the vast majority of the fruit and vegetable varieties in the grocery store were either created by hundreds - sometimes thousands - of years of intensive plant breeding and human selection or by chance mutation. For example, the navel orange (called the Washington or Bahia navel) that is the foundation of the Southern California citrus industry was apparently a "single mutation in 1820 in an orchard of sweet oranges planted at a monastery in Brazil".
Growers in India are believed to have produced what is now considered the modern lemon about AD 100, after decades of crossing it with smaller citrus varieties.
In more modern times, UC Riverside scientists have developed some best-selling fruits, including the Oroblanco grapefruit-pummelo hybrid, with its surprisingly sweet taste, and the tangy Gold Nugget mandarin.
So the next time you read about a new "eat like a 'cave man' diet" or hear someone complaining about "unnatural" fruit varieties, remember what we eat today is a product of human intervention, not "nature", and we would likely find true wild varieties unappetizing.
(The graphic is from the web site of Professor Mikeal Roose. There is a more schematic version in the LA Times article (free registration or bugmenot to read).
The tree is the parent navel orange tree in Riverside, "the source of all of California's multi-million dollar navel orange industry".)
Tags: orange, plant breeding