Jump to content

Navel Oranges


DonRocks
 Share

Recommended Posts

I never knew that the Navel Orange (the "navel" is the protrusion which contains a second fruit) was the result of a mutation that occurred in Brazil around 1810-1820.

More importantly, all naval oranges are not only the same species, but the same individual.  In other words, genetically speaking, there is only one naval orange tree in the entire world -- all the "trees" that you see out there producing the fruit are clones from the same original individual.  There is no genetic diversity at all.   Among other things, this suggests that If some nasty pest were to suddenly show up and attack, the population of these orange trees would have essentially no genetic defenses, and would be subject to possibly being wiped out worldwide practically overnight.

Something similar to this is happening right now to bananas.  The world banana crop is mostly a single cloned variety, the Cavendish, which is being attacked by a new version of the Panama disease that wiped out the previous banana type, the Gros Michele (known affectionately in the business as the Big Mike), in the 50's.  The disease (Panama TR4) is certainly going to wipe out the Cavendish eventually, so the race is now on between the geneticists and the disease to see if the industry will be saved.  In a few years we'll know if we still have easy access to the big inexpensive bananas we are all accustomed to, or whether there will only be a few varieties of very expensive and small types available on the market.  The latter are often quite tasty, but very difficult to cultivate and transport, certainly on anything resembling a large scale.

Link to comment
Share on other sites

i think i remember reading the same thing about all red delicious apples--that all the trees that now exist are grafts of the original tree (or of its original grafts). The lack of genetic diversity is worrisome of course, but, to me at least, it's also amazing to realize that this whole crop came from one plant, and that all those trees out there are, in a way, the same tree. 

Link to comment
Share on other sites

i think i remember reading the same thing about all red delicious apples--that all the trees that now exist are grafts of the original tree (or of its original grafts). The lack of genetic diversity is worrisome of course, but, to me at least, it's also amazing to realize that this whole crop came from one plant, and that all those trees out there are, in a way, the same tree. 

If you red the Botany of Desire by Michael Pollan, he has 4 sections: Apples, Potatoes, Tulips, and Marijuana.  As mentioned in the banana thread, the potato famine according to the book was caused by lack of diversity and a blight which wiped out the particular variety which was common to Ireland.  With apples, all varieties are the result of a graft.  The seeds in all apples will grow a genetically different type of apple than the "parent".  So, all honeycrisps, granny smiths, red delicious, cameo, fuji, empire, etc. are the propagated through a graft.  I cannot recommend the book enough.  A very good read.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...