Today, wheat is the grown on more land than any other crop
It provides 20% of global calories and protein. But improvements are difficult because wheat is so genetically complex – many species are polyploids with up to three sets of chromosomes as is the case with (hexaploid) bread wheat.
The Green Revolution of the 1940s-1960s introduced improvements such as dwarfing genes and shuttle breeding. However, to meet future demand, crop improvements must be achieved more rapidly.
The world must produce 60% more wheat by 2050, according to the Wheat Initiative, an international body coordinating wheat research. And with genetic improvements taking up to 20 years using current approaches the race is on.
Wheat – the past
Wheat is a grass, which was first cultivated 10-12,000 years ago in the Fertile Crescent from the Nile in Egypt to the Euphrates in modern Iraq.
The Green Revolution of the 1940s-1960s introduced improvements such as dwarfing genes which allowed resources to be diverted towards seed production and made plants more resistant to wind and rain.
Norman Borlaug, architect of the Green Revolution in wheat, introduced shuttle breeding techniques allowing breeders to grow two generations of wheat each year.
21st century solutions
Genomic and technological breakthroughs have delivered fresh impetus to wheat research. It means that instead of having to use simpler model species such as Arabidopsis thaliana, the wheat community can work directly with the crop.
- 2013: CRISPR/Cas9, or gene editing is first reported in the scientific literature
- 2014: Chromosome-based draft genome sequence of wheat published in the journal Science
- 2015: Open access genomics resources are published. These include PolyMarker, a web-based portal which designs specific genetic markers in wheat and is used by many UK and European molecular breeders
- 2015: Two free, open source resources draw together information. These are wheat-expression.com and wheat-training.com
- 2016: Approaches using mutant and natural populations allow speed cloning of genes from wheat and their wild relatives
- 2017: The most accurate and complete DNA sequence analysis of the wheat genome is published
- 2017: A free database of ten million mutations in bread and pasta wheat varieties is launched. The break-through mutant resource called Wheat TILLING speeds up the development of sought after traits
- 2017: Designing Future Wheat – A national UK wheat research program involving more than 25 groups of scientists is funded through the BBSRC’s Institute Strategic Programs for five years
- 2017: First version of chromosome-based reference sequence for wheat is made available
- 2018: Speed-breeding protocols are published. Up to six generations of wheat can be grown each year, compared to the usual two or three
- 2018: OpenWildWheat.org International consortium launches new genomic tool, a genetic directory including the sequences of 150 wild wheats belonging to a goat grass species called Aegilops tauschii ssp. strangulata. This will enable breeders to scan the genomes of wild relatives of modern wheat to find the disease-fighting properties lost during the process of domestication
- 2018: CRISPR/Cas9 has become the tool of choice for gene-editing in plants, not only to knock out genes but also to edit within genes
- 2018: Professor Graham Moore uses CRISPR/Cas9 derived mutants to introduce useful traits in to wheat