Skip to comments.Maize Reveals Traces Of Old Breeding Project
Posted on 12/02/2004 11:37:33 AM PST by blam
Maize reveals traces of old breeding project
Gene suggests ancient culture selected patterns in its corn.
Teosinte grass (left) compared to "reconstructed" primitive maize, created by crossing teosinte with Argentine pop corn.
© The Doebley Lab
The people of Mesoamerica are largely responsible for the golden corn we grow today, having domesticated tough teosinte grass thousands of years ago and bred it into modern maize.
Researchers have now located the gene responsible for some of the traits that the Mesoamericans were selecting. The discovery should help scientists understand how plants develop, and reveals just how strict the ancient breeding regime for maize (Zea mays) must have been.
Robert Schmidt, a maize researcher at the University of California, San Diego, and his colleagues were intrigued by a mutant maize that was found in South America in the 1920s. The mutant is unable to grow branches or flowers, and happens to resemble a particular rice mutant in this respect. Because the sequence of the gene that causes the effect is known for rice, Schmidt and his team were able to pin down the sequence in maize.
They called the mutated gene barren stalk1 and were able to show that the normal version of barren stalk1 regulates how the maize plants branch. They report their results in this week's Nature1.
Perhaps by having fewer branches you get bigger seeds. We don't know.
Robert Schmidt University of California, San Diego
But not only does barren stalk1 regulate branching, it is also located within one of five regions that maize researchers have identified as targets of domestication. So, was it one of the genes that the Mesoamericans unknowingly selected for as they tamed teosinte (Zea mexicana)?
To investigate further, the researchers compared the number of variants of the barrenstalk1 gene in teosinte, which still grows wild in Mexico's Sierra Madre, with the number in modern maize.
In teosinte, there are about a dozen common variants of the gene, all of which probably produced subtly different branching patterns in the plants. It is common for this number of variants to be present in a particular species of plant. But in modern maize, only one variant exists, suggesting that the others must have been eliminated by rigorous selective breeding.
"It's a really impressive paper," says Phillip SanMiguel, geneticist at Purdue University in West Lafayette, Indiana, who works with maize.
Why did the Mesoamericans plump so strongly for one branching pattern rather than another? Schmidt's team has not nailed this down yet. But presumably there was something about the branching of maize with that particular variant that was useful.
"In combination with other genes it probably had some impact on the architecture that was important to the Mesoamericans," suggests Schmidt. "Perhaps by having fewer branches you get bigger seeds. We don't know."
The next step will be to paste all the variants of the barren stalk1 that exist in teosinte into modern maize, Schimdt's team says. Once you see what the differences are in maize, it will be easier to guess why a particular variant was chosen.
Yes, just one more societal improvement "stolen by evil Europeans and claimed as their own...blah, blah, blah"
Wow. Bitter much? ;0)
Willie Maize was one of my favorite baseball players.
The secret is in the walls at Macchu Picchu:
Please FREEPMAIL me if you want on, off, or alter the "Gods, Graves, Glyphs" PING list --
Archaeology/Anthropology/Ancient Cultures/Artifacts/Antiquities, etc.
The GGG Digest -- Gods, Graves, Glyphs (alpha order)
Hmm. Here we have fireweed and diamond willow. Maybe we can get something like a silk apple tree by crossing them, something that would thrive in the harsh subarctic growing conditions and feed the moose even better than fireweed and diamond willow by themselves.
Genetic Engineering is much faster....Mmmmm, yummy GMOs.....
"The discovery of a tomb filled with decapitated bodies suggests Mexico's 2,000 year-old 'Pyramid of the Moon' may have been the site of horrifically gory sacrifices, archeologists said on December 2, 2004. The tomb at Teotihuacan, the first major city built in the Americas, whose origins are one of history's great mysteries, also held the bound carcasses of eagles, dogs and other animals. The Pyramid is seen in this September 2 file photo. (Henry Romero/Reuters)"
Thu Dec 2, 5:03 PM ET
pong for litter
So, was it one of the genes that the Mesoamericans unknowingly selected for as they tamed teosinte (Zea mexicana)?
The arrogance and self-importance of IV tower "intellectuals" is staggering in its delusions of grandeur and import.
I have read somewhere that it has fairly ancient origins and was a staple throughout Mexico and the American Southwest..
Hope = Hopi..
I recall reading (probably 10 or 15 years ago) about the (figurative) shootout between the alleged dean of corn genetics ("Teosinte", from Wisconsin I think) and someone who was apparently at that time the lone advocate for the third model shown here.Early plant domestication in MesoamericaReferring to these mysterious origins, Kent Flannery (1986) has called maize the "most controversial and most enigmatic of any major cultivated plant." All specimens of primitive maize known from archaeological sites are domesticated forms. Maize is not included in the taxa considered above under "wild-food production," nor does it appear on the list of the earliest cultigens. This is because it simply wasn't there. Identifying the wild progenitor(s?) of maize means reconstructing genetic events with little material corroboration, and so has been the subject of much speculation and debate for at least 100 years. Opinions are numerous, but currently the three leading hypotheses are: the Wild Maize Hypothesis, the Orthodox Teosinte Theory, and the Catastrophic Sexual Transmutation Theory (as shown in Benz and Iltis 1992).
Athena Review Vol.2, no.1
FR Lexicon·Posting Guidelines·Excerpt, or Link only?·Ultimate Sidebar Management·Headlines
PDF to HTML translation·Translation page·Wayback Machine·My Links·FreeMail Me
Gods, Graves, Glyphs topic·and group·Books, Magazines, Movies, Music
But in modern maize, only one variant exists, suggesting that the others must have been eliminated by rigorous selective breeding.
Ok im getting a freaking migraine here trying to figure this out.Does anyone on this thread know exactly how in the hell you can unknowingly rigorously selectively breed a plant ?Am i missing something?
I understood it to mean that they were rigorously selecting for one trait and because of the genetic connection unknowingly selected for another trait as well. These things are not very clear sometimes.
ok that makes more sense now and my migraine is gone :-)
I get those. Turns my brain to rummy.
|GGG managers are SunkenCiv, StayAt HomeMother & Ernest_at_the_Beach|
Just updating the GGG info, not sending a general distribution.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.