Traditional breeding involves crossing two varieties and selecting the best performing among the progeny. Predictive breeding is a more advanced technique where specific parts of the genome most likely to contain beneficial genes are identified.
Genomic sequencing and the availability of genetic linkage maps can play a major part in predictive breeding efforts by linking beneficial traits to specific parts of the genome. Researchers and breeders use genetic markers to construct linkage maps, which help to identify useful genes. They are also vital to marker-assisted crop breeding, where the maps and markers can greatly accelerate the breeding in of new improved traits.
However, for key crops such as bread wheat and oilseed rape, the use of this kind of genomics-based predictive crop breeding is severely hampered due to the complicated genomes that these species possess. Many important crop plants are polyploid, possessing several sets of chromosomes. Bread wheat, for example, contains three pairs of chromosomes derived from multiple hybridisation events that occurred between two other wheat species relatively recently in its ancestry. To try to overcome this problem, a team from the John Innes Centre and The Genome Analysis Centre (TGAC), which are strategically supported by the BBSRC, combined sequence data from different sources to construct genetic linkage maps.
The team led by Professor Ian Bancroft worked on oilseed rape, which as well as being an important oil crop also plays a key role in crop rotation strategies. Its oil has industrial applications and its straw can be used for biofuel production. Like bread wheat, oilseed rape (Brassica napus) has a complicated genome, having recently been formed from related species Brassica rapa and Brassica oleracea.
The strategy adopted by the group involves integrating the available sequence data for oilseed rape with that of its ancestral progenitors, and also that of a more distantly-related species for which high-quality genome sequence data is available, in this case the model plant Arabidopsis thaliana.
Instead of trying to sequence the DNA, the team focussed on the RNA transcribed from the DNA when the genetic code is expressed. The complete set of all of this transcribed RNA is known as the transcriptome.
TGAC used the Illumina GAII platform for the study, producing a series of consistently high quality sequence datasets from expressed genes.
The team analysed the transcriptome in juvenile leaves, which gives an overview of all of the genes that are expressed in that tissue. Using the sequence variation the researchers were able to construct genetic linkage maps in oilseed rape, eventually identifying over 23,000 markers. This allowed them to align the oilseed rape genome with that of Arabidopsis thaliana and also to sequence data from oilseed rape's two progenitor species.
This method of dissecting the genome of polyploid crops is likely to be equally applicable to other important crops. Bread wheat is a prime candidate for this, using the model grass Brachypodium distachyon in the place of Arabidopsis.
"Dissecting the genome of oilseed rape like this opens up the possibility of using predictive breeding techniques that will really help with the production of improved varieties" said Prof. Bancroft.
This study was published in Nature Biotechnology and funded by the BBSRC, the Department for Environment, Food and Rural Affairs and the China National Basic Research and Development Program.
Andrew Chapple | EurekAlert!
Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München
Second research flight into zero gravity
21.10.2016 | Universität Zürich
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences