CIUDAD OBREGÓN, MEXICO Ravi Singh compares plots of wheat lines growing in the fields of Obregón to determine which lines have potential as new varieties. Relying on reams of statistical breeding data and an experienced eye, the head of bread wheat improvement at the International Maize and Wheat Improvement Center (CIMMYT) evaluates plants for resistance to rusts and other diseases, height, tillering ability, grain fill or the mass and size of the spikes, and general vigor or robustness. After detailed evaluation, the fate of the plant is determined: it is selected for advancement and harvested for seed for a yield trial, or it is passed over. With his team, Singh surveys tens of thousands of small wheat plots each season.
Posts Tagged ‘breeding’
As part of varied approaches at the International Maize and Wheat Improvement Center (CIMMYT) to unleash the power of wheat biodiversity, researchers from India and Mexico have been mobilizing native diversity from ancestral versions of wheat and related grasses to heighten the crop’s resilience to dryness and heat—conditions that have held back wheat yields for several decades and will worsen as earth’s climate changes. Now their results are beginning to reach breeders worldwide.
by Rajv Sharma & Zaki Afshar / February 17, 2017
KABUL (CIMMYT)- Inadequate access to new disease-resistant varieties and short supplies of certified seed are holding back wheat output and contributing to rising food insecurity in Afghanistan, according to more than 50 national and international wheat experts.
Wheat scientists and policymakers discussed challenges to the country’s most-produced crop during a two-day meeting at Agricultural Research Institute of Afghanistan (ARIA) headquarters in Kabul, as part of the 5th Annual Wheat Researchers’ Workshop in November 2016. They took stock of constraints to the 2017 winter wheat crop, including dry autumn weather and rapidly-evolving strains of the deadly wheat disease known as yellow rust.
EL BATAN, Mexico (CIMMYT)—Scientists from two of the world’s leading agricultural research institutes will embark on joint research to boost global food security, mitigate environmental damage from farming, and help to reduce food grain imports by developing countries.
At a recent meeting, 30 scientists from the International Maize and Wheat Improvement Center (CIMMYT) and Rothamsted Research, a UK-based independent science institute, agreed to pool expertise in research to develop higher-yielding, more disease resistant and nutritious wheat varieties for use in more productive, climate-resilient farming systems.
Just published by CIMMYT and WHEAT, the report “Impacts of International Wheat Improvement Research 1994-2014,” shows that varieties on nearly half the world’s wheat lands overall — as well as 70 to 80 percent of all wheat varieties released in our primary target regions (South Asia, Central and West Asia and North Africa) — are CGIAR related. Other key findings include the following:
- Fully 63 percent of the varieties featured CGIAR genetic contributions. This means they are either direct releases of breeding lines from CIMMYT and ICARDA or have a CGIAR line as a parent or more distant ancestor.
- Yearly economic benefits of CGIAR wheat breeding research ranged from $2.2 to $3.1 billion (in 2010 dollars), and resulted from annual funding of just $30 million, representing a benefit-cost ratio of between 73:1 and 103:1, even by conservative estimates.
- In South Asia, for example, which is home to more than 300 million undernourished people and whose inhabitants consume over 100 million tons of wheat a year, 92 percent of the varieties carried CGIAR ancestry.
By Mike Listman
In early outcomes, partners in the International Wheat Yield Partnership (IWYP) are finding evidence that increased photosynthesis, through high biomass, improvements in photosynthetic efficiency, and improved plant architecture, can help make wheat more productive, as the Partnership progresses toward meeting its aim of raising the crop’s genetic yield potential by up to 50% over the next 20 years.
This and other work, and particularly partners’ roles and operating arrangements, were considered at the first official annual IWYP Program Conference. This was held at the Norman E. Borlaug Experiment Station near Ciudad Obregón, Mexico, 8-10 March 2016, following the funding and commencement of the Partnership’s first eight projects, according to Jeff Gwyn, IWYP Program Director.
“The aim of the conference was for participants to learn about everyone else’s work and to integrate efforts to realize synergies and added value,” said Gwyn, noting that some 35 specialists from nearly 20 public and private organizations of the Americas, Europe, Oceania, and South Asia took part.
In a ceremony on 13 February 2016, scientist Ravi Singh will be named become a Fellow of the American Association for the Advancement of Science (AAAS) for “distinguished contributions to the field of agricultural research and development, particularly in wheat genetics, pathology and breeding.” Singh leads wheat improvement and rust disease resistance research at CIMMYT.
Additionally, two CIMMYT scientists will speak at an AAAS session on 14 February titled “Pathogens Without Borders.” The session will highlight the work of David Hodson and Jessica Rutkoski who, like Singh, are researchers in the Durable Rust Resistance in Wheat (DRRW) project – part of the Borlaug Global Rust Initiative at Cornell University.
To read the complete story on the Thompson-Reuters Foundation News page that describes the event and global efforts to stop wheat rust disease, click here.
A recent study by a global team of researchers from CIMMYT, ICARDA, and the Global Crop Diversity Trust has uncovered a treasure trove of wheat genetic diversity to address drought and rising temperatures—constraints that cut harvests for millions of farmers worldwide and which are growing more severe with each passing year.
The team studied the molecular diversity of 1,423 spring bread wheat accessions that represent major global production environments, using high quality genotyping-by-sequencing (GBS) loci and gene-based markers for various adaptive and quality traits.
They discovered thousands of new DNA marker variations in landraces known to be adapted to drought (1,273 novel GBS SNPs) and heat (4,473 novel GBS SNPs), opening the potential to enrich elite breeding lines with novel alleles for drought and heat tolerance. New allelic variation for vernalization and glutenin genes was also identified in 47 landraces from Afghanistan, India, Iran, Iraq, Pakistan, Turkmenistan, and Uzbekistan.
Mean diversity index (DI) estimates revealed that synthetic hexaploids—created by crossing wheat’s wild grass ancestor Aegilops tauschii with durum wheat—are genetically more diverse than elite lines (DI = 0.267) or landraces (DI = 0.245). Lines derived from such crosses are already playing an increasingly important role in global and national breeding programs.
Identifying and mobilizing useful genetic variation from germplasm banks to breeding programs is key to sustaining crop genetic improvement. The results have already been used to select 200 diverse germplasm bank accessions for pre-breeding and allele mining of candidate genes associated with drought and heat stress tolerance, thus channeling novel variation into breeding pipelines.
Published in the paper Exploring and Mobilizing the Gene Bank Biodiversity for Wheat Improvement, the research is part of CIMMYT’s ongoing Seeds of Discovery project visioning towards the development of high yielding wheat varieties that address future challenges from climate change.
By Mike Listman
Scientists have sequenced and described a gene that can help wheat to resist four serious fungal diseases, potentially saving billions of dollars in yearly grain
losses and reducing the need for farmers to use costly fungicides, once the gene is bred into high-yielding varieties.
A global research team isolated the wheat gene Lr67, revealing how it hampers fungal pathogen growth through a novel mechanism.
The study, which was published in Nature Genetics on 9 November, involved scientists from the International Maize and Wheat Improvement Center (CIMMYT), the Chinese Academy of Agricultural Sciences (CAAS), Mexico’s National Institute of Forestry, Agriculture, and Livestock Research (INIFAP), the Norwegian University of Life Sciences and scientists from Australia, including the Commonwealth Scientific and Industrial Research Organisation (CSIRO), the University of Newcastle, and the University of Sydney.
According to Ravi Singh, CIMMYT distinguished scientist, wheat breeder, and co-author of the new study, Lr67 belongs to a group of three currently-known “magic” genes that help wheat to resist all three wheat rusts and powdery mildew, a disease that attacks wheat in humid temperate regions. The genes act in different ways but all slow — rather than totally stopping — disease development. When combined with other such partial resistance genes through breeding, they provide a strong, longer-lasting protection for plants, boosting food security.
To read more about Lr67‘s cloning and resistance type, click here.
The International Wheat Yield Partnership (IWYP) will recommend around US $20 million in grants awards from its funders for a selection of 8 research projects by leading institutes to increase wheat’s photosynthetic and energy-use efficiency and harness the genetics behind key components of yield.
Resulting from a January 2015 call for competitive research proposals, the projects fit the IWYP goal of raising the genetic yield potential of wheat by up to 50% in the coming 20 years.
To read more about the projects, IWYP, and the Initiative’s funders, click here.