Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Map of Variation in Maize Genetics Holds Promise for Developing New Varieties

23.11.2009
A new study of maize has identified thousands of diverse genes in genetically inaccessible portions of the genome. New techniques may allow breeders and researchers to use this genetic variation to identify desirable traits and create new varieties that were not easily possible before.

Publishing in the Nov. 19 issue of Science, the researchers, whose senior and first author are at Cornell, have identified the first map of haplotypes – sets of closely linked gene variants known as alleles – in the maize genome. They have identified and mapped several million allele variants among 27 diverse inbred maize lines. The lines selected for study included a cross-section of maize types commonly used for breeding while also representing worldwide maize diversity.

The haplotype map “will help develop molecular markers and tools that breeders and geneticists around the world can use to study maize and improve maize varieties,” said Ed Buckler, the paper’s senior author, a USDA-ARS research geneticist in Cornell’s Institute for Genomic Diversity and an adjunct professor of plant breeding and genetics. Michael Gore, a graduate student in Buckler’s lab, is the paper’s lead author.

The other co-authors are affiliated with the U.S. Department of Agriculture’s Agricultural Research Service (USDA-ARS), Cold Spring Harbor Laboratory and University of California-Davis.

In the last century, maize breeders have found limitations in recombination (the ability to shuffle genetic variation), where large regions genetic material fail to recombine near the chromosome’s center, called the centromere. To overcome this, breeders have crossed two complementary lines, resulting in a new line with higher yields and vigor.

However, because large regions of the maize chromosome are less accessible, breeders cannot arrive at optimal genetic combinations. The study has revealed a great deal of genetic variation near the chromosomes’ centromeres, which resist recombining. Now, breeders can use molecular markers to identify desirable genetic variants and new genetic technologies to move the desired variation onto the same chromosomes and create new, more productive lines with desired traits.

The study revealed more than 100 large regions (selective sweeps) on the genome where breeders selected for a gene during domestication. In doing so, genetic diversity was lost around those genes.

The study also identified regions of genes shared by all maize species as well as regions that are different based on the geographic adaptations of lines of plants. For example, the study identified almost 200 highly differentiated regions that result from adaptations in tropical and temperate maize.

“This survey of genetic diversity provides a foundation for uniting breeding efforts across the world and for dissecting complex traits through genomewide association studies,” said Buckler.

The first complete sequence of the maize genome appears in the same issue of Science.

The haplotype study was funded by the National Science Foundation and the USDA-ARS.

Blaine Friedlander | Newswise Science News
Further information:
http://www.cornell.edu

More articles from Agricultural and Forestry Science:

nachricht Kakao in Monokultur verträgt Trockenheit besser als Kakao in Mischsystemen
18.09.2017 | Georg-August-Universität Göttingen

nachricht Ultrasound sensors make forage harvesters more reliable
28.08.2017 | Fraunhofer-Institut für Zerstörungsfreie Prüfverfahren IZFP

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: LaserTAB: More efficient and precise contacts thanks to human-robot collaboration

At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.

Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Fraunhofer ISE Pushes World Record for Multicrystalline Silicon Solar Cells to 22.3 Percent

25.09.2017 | Power and Electrical Engineering

Usher syndrome: Gene therapy restores hearing and balance

25.09.2017 | Health and Medicine

An international team of physicists a coherent amplification effect in laser excited dielectrics

25.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>