Posts Tagged: wheat
Growing cereal crops with less fertilizer
Discovery could reduce nitrogen pollution, save farmers billions
Researchers at the University of California, Davis, have found a way to reduce the amount of nitrogen fertilizers needed to grow cereal crops. The discovery could save farmers in the United States billions of dollars annually in fertilizer costs while also benefiting the environment.
The research comes out of the lab of Eduardo Blumwald, a distinguished professor of plant sciences, who has found a new pathway for cereals to capture the nitrogen they need to grow.
The discovery could also help the environment by reducing nitrogen pollution, which can lead to contaminated water resources, increased greenhouse gas emissions and human health issues. The study was published in the journal Plant Biotechnology.
Nitrogen is key to plant growth, and agricultural operations depend on chemical fertilizers to increase productivity. But much of what is applied is lost, leaching into soils and groundwater. Blumwald's research could create a sustainable alternative.
“Nitrogen fertilizers are very, very expensive,” Blumwald said. “Anything you can do to eliminate that cost is important. The problem is money on one side, but there are also the harmful effects of nitrogen on the environment.”
A new pathway to natural fertilizer
Blumwald's research centers on increasing the conversion of nitrogen gas in the air into ammonium by soil bacteria — a process known as nitrogen fixation.
Legumes such as peanuts and soybeans have root nodules that can use nitrogen-fixing bacteria to provide ammonium to the plants. Cereal plants like rice and wheat don't have that capability and must rely on taking in inorganic nitrogen, such as ammonia and nitrate, from fertilizers in the soil.
“If a plant can produce chemicals that make soil bacteria fix atmospheric nitrogen gas, we could modify the plants to produce more of these chemicals,” Blumwald said. “These chemicals will induce soil bacterial nitrogen fixation and the plants will use the ammonium formed, reducing the amount of fertilizer used.”
Blumwald's team used chemical screening and genomics to identify compounds in rice plants that enhanced the nitrogen-fixing activity of the bacteria.
Then they identified the pathways generating the chemicals and used gene editing technology to increase the production of compounds that stimulated the formation of biofilms. Those biofilms contain bacteria that enhanced nitrogen conversion. As a result, nitrogen-fixing activity of the bacteria increased, as did the amount of ammonium in the soil for the plants.
“Plants are incredible chemical factories,” he said. “What this could do is provide a sustainable alternative agricultural practice that reduces the use of excessive nitrogen fertilizers.”
The pathway could also be used by other plants. A patent application on the technique has been filed by the University of California and is pending.
Dawei Yan, Hiromi Tajima, Howard-Yana Shapiro, Reedmond Fong and Javier Ottaviani from UC Davis contributed to the research paper, as did Lauren Cline from Bayer Crop Science. Ottaviani is also a research associate at Mars Edge.
The research was funded by the Will W. Lester Endowment. Bayer Crop Science is supporting further research on the topic.
Editor's note: Blumwald is affiliated with UC Agriculture and Natural Resources through the Agricultural Experiment Station at UC Davis.
/h3>/h3>UC Davis to lead $15 million research into climate-change resistant wheat
The project will also train plant breeders for the future
Wheat products account for roughly 20% of what people eat every day around the globe. As climate changes, wheat crops must adapt to new weather patterns to keep up with demand.
The University of California, Davis, is leading a five-year, $15 million research project to accelerate wheat breeding to meet those new climate realities, as well as to train a new generation of plant breeders.
“Everything is less stable,” said Jorge Dubcovsky, a plant sciences distinguished professor who is leading the grant research. “Everything is changing so you need to be fast. You need to be able to adapt fast.”
The grant from the U.S. Department of Agriculture's National Institute of Food and Agriculture will create a coordinated consortium of 41 wheat breeders and researchers from 22 institutions in 20 states. Researchers from Mexico and the United Kingdom are also participating.
Breeding needs to speed up
“Breeding crops for the future will require new traits, breeding platforms built for quick transfer of traits to elite cultivars, coordination of breeding efforts in public and private domains, and training for current and future plant breeders and researchers,” NIFA said in an announcement about this grant and others related to breeding.
The program involves on-the-ground research, identifying molecular markers and data analysis from multiple institutions to determine genes that will help wheat crops mitigate the effects of climate change. Plant breeding will follow to prove out those findings.
Wheat is unlike other crops in that 60% of the plant varieties — generating about $4 billion in annual production — are developed by public breeding programs rather than private corporations. In many states, wheat growers tax themselves to support basic breeding efforts at public institutions like UC Davis.
Increased coordinated research
The NIFA grant money will lead to more coordinated, sophisticated research. “This grant allows us to do breeding at a level that a good, modern company would do,” Dubcovsky said. “This grant is essential to maintain modern and effective public breeding programs in the U.S.”
The consortium will bring together data and research from across institutions, allowing for more expansive analysis while reducing redundancies. “We can take advantage of the data from everybody,” he said. “By doing that we don't need to duplicate efforts.”
A team in Texas will analyze plant images taken from drones at each institution to extract information about plant growth, water use, nitrogen levels and other data. “Using technology, we can see beyond our human capabilities,” Dubcovsky said. “You can extract a huge amount of information from every plant variety.”
The data from those images will allow researchers to document the plants throughout the life cycle and determine which plants fare better under certain conditions. Genotyping will help researchers obtain information about the plant genome. The combination of these two types of data could speed up breeding cycles, helping wheat crops adapt to a changing environment.
“If we can breed fast, we can adapt to change,” Dubcovsky said. “We are trying to make sustainable improvements in time.”
Training the next generation
The project will also train a cohort of 20 plant Ph.D. students in active breeding programs where they will participate in fieldwork, collect data from drones and DNA samples, and learn to integrate that information to accelerate wheat breeding. The students will participate in online and face-to-face workshops, as well as educational events and national scientific conferences.
Colorado State University, Cornell University, Kansas State University, Michigan State University, Montana State University, Oklahoma State University, Purdue University, South Dakota State University, Texas A&M University, University of Idaho, University of Illinois, University of Minnesota, University of Nebraska, University of Wisconsin, Utah State University, Virginia Tech, Washington State University, and U.S. Department of Agriculture Agricultural Research Service branches in North Dakota, Washington, Kansas and North Carolina are also participating in the consortium.
/h3>/h3>/h3>/h2>UC Davis team identifies wheat gene that increases yield
The findings could help growers produce more wheat without expanding operation
A team of scientists from University of California, Davis, have identified a new gene variant in wheat that can increase the amount of the grain produced, new research published in the journal PLOS Genetics finds.
Wheat is a staple of food diets worldwide and the gene discovery could allow farmers to grow more food without increasing land use. Increased yield could also lower consumer prices, making the crop more accessible.
“We have a growing human population that likes to eat every day,” said Jorge Dubcovsky, a plant sciences distinguished professor who led the research. “We need to produce more wheat in the same space so we need plants that are more productive.”
The researchers found a gene – WAPO1 – that controls the maximum number of grains in a wheat spike. Breeding the beneficial gene variant into the plants could delay the formation of the terminal spikelet, providing room for more grains to grow in each spike rather than ending production of grain.
WAPO1 is one of the first genes discovered that can affect wheat yield. “We are trying to make more productive wheat varieties and we are starting to understand how that trait is controlled,” Dubcovsky said.
Pasta wheat lacking the gene
The gene variant for high grain number is found frequently in bread wheats but not in pasta wheats. By breeding the beneficial gene variant into those pasta wheat varieties, growers could increase yield by 4% to 5% in cultivars that have the biomass capacity to fill the extra grains.
“We developed molecular markers to select for the form of that gene to produce increased yield,” Dubcovsky said. “It's a significant step forward.”
Previous research by the team mapped the gene and identified others that could affect yield. This research confirmed those findings for WAPO1.
Discovery on path to future yield increases
The WAPO1 gene is part of a network of genes that work together to control yield, and researchers need to identify the best variant combinations to maximize yield. Solving this puzzle can lead to better production rates.
“We will continue to try to understand the network of genes that control the yield of wheat,” he said.
Saarah Kuzay, Huiqiong Lin, Chengxia Li, Shisheng Chen, Daniel P. Woods and Junli Zhang from UC Davis also contributed to the research, as did scientists from Howard Hughes Medical Institute, Heinrich Heine University and Peking University Institute of Advanced Agricultural Sciences.
Funding was provided by USDAs National Institute of Food and Agriculture's Food Research Initiative, the International Wheat Yield Partnership and Howard Hughes Medical Institute.
/h3>/h3>/h2>New ‘big data’ tools help California wheat farmers reduce fertilizer guesswork
Growers in California grapple with plenty of climate uncertainty – but a new set of tools can help wheat farmers make crucial fertilizer decisions with more precision and confidence.
An interactive website integrates these tools – developed or adapted by researchers at the University of California, Davis and University of California Cooperative Extension – that provide farmers with recommendations for applying nitrogen fertilizers, specific to their own sites and conditions.
While factoring in those weather variables, the management tool also draws data from two indicators of nitrogen sufficiency or deficiency: the results of a soil nitrate quick test (a simple test previously used in vegetable crop systems along the coast), and comparisons of plant health in the broader field to that in a “nitrogen-rich reference zone” (a practice originally developed in the Midwest).
Using them in tandem, in the context of California wheat growing, is a novel approach. In a Nov. 4 webinar, Lundy will introduce the use of the nitrogen-rich reference zone, a small area in a field where extra fertilizer is added at the beginning of the season.
“This project is a unique example of digital agriculture at work in an applied setting,” he explained. “We are integrating ‘big data' sources like site-specific soil and weather data, as well as satellite, drone and other sensor measurements into an interactive web interface. This allows users to receive straightforward yet highly customized recommendations from somewhat complex agronomic models.”
The team conducted 11 on-farm demonstrations in fields representing a wide range of agroecosystems, including the Sacramento Valley, San Joaquin Valley, Delta region, and Tulelake Basin.
Fritz Durst, a western Yolo County-based grower who participated in one of the case studies, said that the process of gathering the data was “actually pretty simple” and the tool “eliminates much of the guesswork” for managing nitrogen fertilizers.
“This tool is extremely helpful for me to make decisions about the most efficient and cost-effective method for applying nitrogen to my wheat,” Durst said.
In addition to potentially increasing crop productivity and farmer net-income, the tool can benefit the environment by reducing the amount of nitrate leaching from fertilizer applications, according to Lundy.
“It's not only trying to say how much fertilizer to put down, sometimes it's trying to confirm you don't really need any fertilizer,” he said.
More resources and events related to the Nitrogen Fertilizer Management Tool for California Wheat – including demonstration activities – will appear on the UC Small Grains blog.
Pasta salad - more nutritious than ever
The ever popular pasta salad is sturdy and economical, but is it nutritious?
It sure can be, and research from UC Davis Department of Plant Sciences professor Jorge Dubcovsky is helping to make that so. Dubcovsky’s team discovered a gene in domesticated wheat that had been damaged, a gene that controls the distribution of nutrients to the grains in healthy grain plants. What’s more, they discovered a copy of that damaged gene in wild wheat, enabling them (and others) to breed new varieties with substantially increased levels of protein, iron and zinc.

Wheat provides about 20 percent of all the calories people consume worldwide. In other words, we eat a lot of it – it’s second only to rice as a human source of calories. Sometime during its domestication (some 10,000 years ago) wheat underwent a change that lowered the protein, zinc and iron content in its grain.
In 2006, after years of mapping, Dubcovsky and his team discovered the culprit - a mutation in a gene called NAM-B1. In healthy grain plants, NAM-B1 controls the remobilizing and distribution of nutrients to the grains when the leaves die off. Without a working copy of the gene, cultivated wheat is not a good processor of its nutrients, so large amounts of protein, iron and zinc are left in its straw.
Dubcovsky’s team then examined the ancestors of commercial wheat and found, amazingly enough, a fully functional NAM-B1 gene within the genome of wild emmer wheat. Emmer wheat can be freely crossed with domestic wheat using conventional means, so no controversial genetic engineering methods were needed to restore the lost gene.
The University of California has already released one variety – Lassik - with the increased nutritional punch. Lassik also is genetically improved for stronger gluten and resistance to both stripe-rust and leaf-rust disease. And because the new strains were bred from widely used commercial varieties, the new variety retains its farmer-friendly characteristics such as high yield and consumer-friendly trait like excellent taste.
The new plants are in the public domain, distributed to breeders across the globe. Some 2 billion people around the world lack adequate micronutrients, so more nutritious wheat could make a big difference in fighting world hunger.
So when friends ask, “What’s the secret to your fantastic pasta salad?” you know what to say:
“Protein, iron and zinc.”
For more on what the UC Davis Department of Plant Sciences is doing to make our salads more tasty, nutritious, safe and affordable, see The Spring 2010 Leaflet
Wild wheat, Triticum turgidum ssp. dicoccoides