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Banana to be Sequenced
GodsMadClown writes "New Scientist
reports
that a global consortium plans to sequence the genetic code of a wild banana from east Asia. Because bananas are triploidal instead of diploidal, they are only able to reproduce asexually, which means that it adapts slower than organisms reproducing sexually. 'One rule of joining the consortium is that any invention developed through the project and protected [by patent] will be made available to smallholders through a royalty-free license,' says Emile Frison, director of the International Network for the Improvement of Banana and Plantain."
Actually the banana plant is the worlds largest herb... the banana is still fruit ;)
And they cross breed bananas all the time. You can buy Apple Bananas which are smaller, fatter and sweeter... Ahh the knowledge I have gained from having a dad who sells bananas :)
SA
The Banana is a strange thing cos its both, a banana (the yellow thing you peel and eat) is undoubtedly a fruit (containing the seeds of the plant), though since commercially grown banana plants are sterile, the seeds are reduced to little specks.
However, the banana plant, though it is called a 'banana-tree' in popular usage, is technically regarded as a herbaceous plant (or `herb'), not a tree, because the stem does not contain true woody tissue.
What crazy westerner decided that everyone prefers the typical banana? I happily munched wild bananas while trekking in Northern Thailand and goddam they're like a different fruit. Unimaginably sweet, fragrant...amazing - like nectar. Not the bland lumps sold in UK supermarkets. They are small (offending western male self-perception) and probably don't travel well so thank-you evil corporations for 'deciding' that we prefer this genetically weak alternative so they can make a buck. I hope they DO die out and we 'stuck' with REAL bananas. Zu.
It is not simply true that triploidal plants and animals have to replicate asexual. Cultivated bananas indeed do have 3 chromosomes of each of the 11 different chromosomes available. During meiosis, when two possible parent plants are creating gametes (think of sperm and eggs) by splitting cells with 3 chromosomes of each type into cells with either 1 or 2 of the 3 chromomes.
In the next step, such gametes need to be fertilized, i.e., 2 cells, just like a sperm cell and egg cell, need to be fertilized and merged together. If this results in a cell with 3 chromosomes of each chromosome type, a new banana child can grow from this. But since gametes contain 1 or 2 of each type of chromosome, and they have 11 such types, there is only a 1/2^11 change that this sexual reproduction is succesful.
Note that this only applies to the cultivated banana, as we know it from the super market. And you've probably never eaten a banana with pits in it. Bananas with pits exist, but there's only one in about 2048. These bananas can be used to create new banana trees, and they're different from their not-succesful bananas in that they are a lot smaller, and not edible, if compared to common cultivated bananas.
--- Sigmentation Fault - Comments Dumped
Of course, if they sequence the genome, they may in the future be able to create a much safer, if rather boring, version of Jurassic Park, where we can all "see this astonishing 20th-century fruit(/herb) restored to to life in it's natural environment!!"
"The Milliard Gargantubrain? A mere abacus - mention it not."
In his book, The Botany of Desire , Michael Pollan devotes a chapter to the apple and discusses at some length a similar problem. Apple trees are grown from cuttings from older trees already known to produce tasty apples. (The seeds in any given apple are all completely genetically different from the apple they came from and will not produce a tree of similarly-tasty fruit.)
Almost all the apple varieties we consume here in the States (Delicious, Gala, Fuji, and several other I can't remember) can trace their genes back to one tree from the 1800s. Whole industries are based upon this rather homogenous crop, and disease could be devasting. The current answer is heavy spraying of pesticides. Diversification of profitable appple varieties would be better though.
Some of the pages from this apple chapter can be read online at Amazon (but not the most interesting ones, of course).
I can't imagine a world without bananas.