Navigation Links
The amazing maze of maize evolution
Date:10/2/2009

Understanding the evolution and domestication of maize has been a holy grail for many researchers. As one of the most important crops worldwide and as a crop that appears very different from its wild relatives as a result of domestication, understanding exactly how maize has evolved has many practical benefits and may help to improve crop yields.

In the October issue of the American Journal of Botany (www.amjbot.org/cgi/content/full/96/10/1798), Dr. Marina Dermastia and colleagues published their research comparing corn kernel development to its closest wild relative: teosinte. This research overturns some commonly held beliefs on the domestication of maize because, unexpectedly, many traits seen in the cellular development of maize kernels that were previously attributed to the process of domestication were observed in the development of the teosinte kernels by Dermastia and her colleagues. "Although the teosinte kernels are morphologically so different from that of maize, their inside is not, Dermastia said. "Although we did not expect fundamental differences between maize and teosinte, the similarities were striking."

Some of the traits thought to be unique to maize but now also found in teosinte include an early programmed cell death for cells in part of the kernel and accumulation of phenolic and flavonoid compounds in the walls of these cells. These developmental changes strengthen the cells, protect them against decay and disease, and increase water conductance. According to Dermastia, "We suggested previously that this process was important for the establishment of the water and assimilate flow to the developing maize kernelin the teosinte kernel, we not only detected programmed cell deathbut also all other phenomena described as related to the transport into the maize kernel." The presence of these traits in teosinte kernels suggests that they are not a consequence of maize domestication.

Other developmental traits they observed in the teosinte kernels included the presence of an enzyme that controls the flow of sugar in the developing seed, which appears to be a common mechanism for sugar uptake in both maize and teosinte.

Dermastia and her colleagues did observe one difference between seed development in teosinte and maize. Endoreduplication, the process of a cell duplicating its DNA without subsequent cell division, is a phenomenon that occurs in the endosperm of cereals, which is the nutritious part of the seed. An increasing rate of endoreduplication results in cells with greater DNA content and, subsequently, increased gene expression and greater sink capacity for the developing seed. Dermastia and her colleagues observed that the distribution of cells with high DNA content in maize differs from that of teosinte. In maize, these cells are found in the upper part of the endosperm, while in teosinte they are distributed throughout the endosperm. The researchers hypothesize that this difference may be related to more efficient starch deposition in maize as a result of domestication.

"Our study indicates that the main differences, beside the teosinte fruitcase and its absence in maize, might lay in the process of endoreduplication in endosperm, Dermastia said. "Knowing the process in more depth might be an important step in improving a most important crop."


'/>"/>

Contact: Richard Hund
rhund@botany.org
314-577-9557
American Journal of Botany
Source:Eurekalert

Related biology news :

1. Researchers find the earliest evidence of domesticated maize
2. Early origins of maize in Mexico
3. Ancient Mexican maize varieties
4. Team finds an economical way to boost the vitamin A content of maize
5. If corn is biofuels king, tropical maize may be emperor
6. Simulating kernel production influences maize model accuracy
7. Transgenic maize is more susceptible to aphids
8. First all-African GM crop is resistant to maize streak virus
9. Genetic conflict in fish led to evolution of new sex chromosomes
10. Frozen assets: NIAID researchers turn to unique resource for clues to norovirus evolution
11. UAB professors book promises solution for teaching evolution without conflict
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/22/2017)... March 21, 2017   Neurotechnology , a ... technologies, today announced the release of the ... provides improved facial recognition using up to 10 ... single computer. The new version uses deep neural-network-based ... and it utilizes a Graphing Processing Unit (GPU) ...
(Date:3/20/2017)... -- At this year,s CeBIT Chancellor Dr. Angela Merkel ... Chancellor came to the DERMALOG stand together with the Japanese Prime Minster ... country. At the largest German biometrics company the two government leaders could ... recognition as well as DERMALOGĀ“s multi-biometrics system.   ... ...
(Date:3/13/2017)... Future of security: Biometric Face Matching software  Continue ... ... to match face pictures against each other or against large databases. The recognition ... ... software for biometric Face Matching on the market. The speed is at 100 ...
Breaking Biology News(10 mins):
(Date:3/24/2017)... Md. , March 24, 2017  Infectex Ltd., ... (MBVF), today announced positive results of a Phase 2b-3 ... therapy regimen in patients with multidrug-resistant pulmonary tuberculosis (MDR-TB). ... scientists at Sequella, Inc. ( USA ) ... A total of 140 patients were enrolled in ...
(Date:3/24/2017)... , March 24, 2017 Agenus Inc. ... immune checkpoint antibodies and cancer vaccines, today announced participation ... 7 th  Annual William Blair and Maidstone Life Sciences ... Alexandria Center in New York, NY ... March 29 at 9:40 am: Robert B. ...
(Date:3/23/2017)... Mass. , March 23, 2017 /PRNewswire/ ... partner to global in vitro diagnostics manufacturers ... of the industry,s first multiplexed Inherited ... disease testing by next-generation sequencing (NGS). The ... were developed with input from industry experts ...
(Date:3/23/2017)... YORK , March 23, 2017 ... ... of death, putting significant strain on health care systems, in ... cancer diagnoses rises, so too does the development of innovative ... minimum side effects. Among the many types of cancer treatments, ...
Breaking Biology Technology: