March 29, 2013
Dr. David Marshall has been awarded the 2012 USDA-Foreign Agriculture Service, Honor Award for his Cross-Agency Team out of the Office of Agricultural Affairs in Pakistan. The USDA Honor Awards are the highest awards bestowed upon USDA employees and private citizens. The Pakistan project is called the Wheat Productivity Enhancement Project (WPEP), and its goal is to develop and distribute disease resistant, high yielding wheat varieties for Pakistan’s wheat farmers.
November 28, 2012
In 2011, the NCSU Small Grains Extension program, led by Dr. Randy Weisz, started providing very short video “crop alerts” that can be accessed using mobile devices. Building on that effort, Weisz and USDA-ARS Small Grains Pathologist Christina Cowger worked with the North Carolina Small Grain Growers Association and professional videographers to film a series of 4- to 6-minute videos on topics related to small grains production. The videos are targeted to small-grain producers and their advisors. The first set of videos went up on Dr. Weisz’s web site in July 2012: http://www.smallgrains.ncsu.edu/video-library.html
Dr. Weisz reports that visits to his web site increased by five to eight times when he began issuing the video alerts. People watched the alerts on their mobile devices, and then accessed his web site for more information. Cowger is featured in videos on identification and management of four common and damaging diseases in Mid-Atlantic wheat production: powdery mildew, leaf rust, Stagonospora nodorum blotch, and Fusarium head blight (scab).
Powdery Mildew Identification & Management
Leaf Rust Identification & Management
SNB Identification & Management
Head Scab Identification & Management
August 18, 2012
The Maize Genetic Diversity Research Group, whose members include Jim Holland, Ed Buckler, Mike McMullen, Sherri Flint-Garcia, Peter Bradbury, and Doreen Ware, won the 2012 Secretary’s Honor Award, the highest Award given by USDA.
Congratulations to Jim and the Group.
May 11, 2011
Researchers at the USDA-ARS Plant Science Research Unit have found a specific gene in corn that appears to be associated with resistance to three important plant leaf diseases.
In a paper published this week in Proceedings of the National Academy of Sciences, ARS plant pathologists and crop scientists pinpoint the gene – glutathione S-transferase – that seems to confer resistance to Southern leaf blight, gray leaf spot and Northern leaf blight, a trio of diseases that cripple corn plants worldwide.
Finding out more about the mechanisms behind complex traits like disease resistance can potentially help plant breeders build the best traits into tomorrow’s corn plants, says paper co-author Dr. Peter Balint-Kurti, a research plant pathologist and geneticist for the U.S. Department of Agriculture-Agriculture Research Service (USDA-ARS) who works in NC State’s plant pathology and crop science departments.
ARS researchers joined lead author Dr. Randy Wisser, an assistant professor at the University of Delaware, and other researchers from the University of Delaware, Cornell University and Kansas State University in examining 300 diverse maize varieties from across the globe which are, on average, as different from one another as humans are from chimpanzees. Using these diverse varieties of corn allowed the researchers to zero in on the regions of the genome responsible for conferring resistance to the three diseases – and thus to varieties that are very resistant to disease.
“We tested the lines for resistance to these three diseases and found that if a line is resistant to one disease, chances are it’s also resistant to the other two,” Balint-Kurti says.
Southern corn leaf blight is a moderate problem in the southeastern United States, Balint-Kurti says, and can be a significant problem in Southeast Asia, southern Europe and parts of Africa. Prevalent in hot, humid climates across the globe, it causes small brown spots on leaves. The spots get larger and eventually spread to the whole plant. Severe infections can cause major corn yield losses. Northern leaf blight can be found in the Midwestern corn belt; it causes cigar-shaped lesions on leaves. Gray leaf spot – which produces an eponymous effect – is found both in the Midwest and Southeast. All three pathogens are so-called necrotrophic fungi, or fungi that kill what they eat.
Balint-Kurti says the study provides “one of the most comprehensive analyses of multiple disease resistance in plants.”
, , , , , , , and Multivariate analysis of maize disease resistances suggests a pleiotropic genetic basis and implicates a GST gene. PNAS 2011 108 (18) 7339-7344.
National Association of Wheat Growers (NAWG) meeting
Dave Marshall presentation
USDA-ARS researchers used an interesting technique to sift through the set of all genes in corn and point out the best candidate areas controlling a specific type of disease resistance. The results may help breeders create a better corn plant.
In a paper published online this week in Nature Genetics, USDA-ARS crop scientists and plant pathologists sifted through millions of genetic sequence variations in the set of all genes in maize (corn) to identify 51 gene regions associated with resistance to Southern corn leaf blight disease – an important plant pathogen.
Finding out more about the mechanisms behind complex traits like disease resistance has the potential to help plant breeders build the best traits into tomorrow’s corn plants, including resistance to some diseases, says Dr. Jim Holland, NC State professor of crop science, research geneticist for USDA-ARS and the corresponding author of the paper.
Holland and study co-authors Dr. Peter Balint-Kurti, a USDA-ARS research plant pathologist and geneticist and Kristen Kump, an NC State graduate student, joined researchers from Cornell University, the University of Delaware and the University of Missouri to examine a set of 5,000 maize varieties called the maize nested association mapping population. Using this population allowed the researchers to zero in on the parts of the genome responsible for conferring resistance.
Holland and Balint-Kurti hope to build upon these results to learn more about how genes confer disease resistance to Southern corn leaf blight and whether they may also provide resistance to other similar types of diseases in corn and other plant species.
NCSU Press Release, January 10, 2011
Kristen Kump, James Holland, Peter Balint-Kurti, Araby Belcher, Marco Oropeza-Rosas, John Zwonitzer, Peter Bradbury, Edward Buckler, Stephen Kresovich, Doreen Ware, Randall Wisser, Michael McMullen. 2011. Genomewide association study of quantitative resistance to Southern leaf blight in the maize nested association mapping population. Nature Genetics.
Mid-Atlantic wheat growers aren’t likely to get any economic benefit by applying fungicides to wheat fields that aren’t infected with fungal diseases. That’s the conclusion of scientists with USDA-ARS and NC State University who conducted the study. The scientists reviewed 42 publicly sponsored tests of strobilurin- and triazole-containing fungicides on soft red winter wheat in experimental plots in North Carolina and Virginia from 1994 to 2010. They found that while the fungicides make economic sense when fungal disease is present, they don’t if there’s no disease.
The scientists’ review was made public earlier this month through the journal Phytopathology’s website at http://apsjournals.apsnet.org/doi/pdf/10.1094/PHYTO-03-10-0096.
NCSU Press Release, Nov. 19, 2010
Best Expert Review Article 2009, Journal of Integrative Plant Biology
Researchers at the ARS Plant Science Research Unit in Raleigh were recognized for their review article published in the Journal of Integrative Plant Biology, issue 4, 2009: "The Ozone Component of Global Change: Potential Effects on Agricultural and Horticultural Plant Yield, Product Quality and Interactions with Invasive Species." The paper, co-authored by Fitzgerald Booker, Kent Burkey and Edwin Fiscus, among others, was selected by the editorial board as the Best Expert Review Article 2009.
ARS Scientists Participate in Bread Flour Project
Researchers at the ARS Plant Science Research Unit in Raleigh, NC, are collaborating on the North Carolina Organic Bread Flour Project. This project aims to link the farmer, the baker, and the miller in North Carolina with the goal of providing a viable market for organic hard and soft wheat and other small grains.
ARS scientists, led by Research Leader David Marshall, are developing the wheat varieties needed to make this collaboration possible. This project is turning into a very effective research and technology transfer program for the agency.
In addition, a Field Day was held on June 17, 2010, where local bakers in the Asheville, NC, area formed a co-op and purchased a stone mill for milling and producing local flour from two new ARS-developed wheat varieties—NuEast and Appalachian White.
ARS & You, August 2010
More Food From Marginal Lands? Perennial Grains Hold Promise Where Annuals Lag
The world needs more food for its growing population, but risks overtaxing the croplands where much of the world’s food is grown. How then to provide more food while keeping a fragile ecosystem safe?
A “Policy Forum” paper in the June 25 edition of the journal Science, co-authored by a crop scientist from North Carolina State University, proposes one way of achieving these seemingly divergent goals: utilizing recent discoveries in genomics to help breed perennial grain plants for use on lands traditionally inhospitable to annual grain crop production.
“Places with food security issues are usually places where cropland is marginal,” says paper co-author Dr. James Holland, a professor of crop science at NC State and research geneticist with the U.S. Dept. of Agriculture who studies genetic variation in corn. “It may be possible to grow perennial rice and wheat in places where annual rice and wheat don’t grow.”
Mick Kulikowski, NCSU NewsRoom Press Release, 06.28.2010
Last year, the U.S. Department of Agriculture’s (USDA) Agricultural Research Service (ARS) created some optimism among millers up and down the East Coast when it announced the release of “NuEast” (a hard red winter wheat) and “Appalachian White” (a hard white winter wheat).
“Millers and bakers in North Carolina as well as on the Eastern seaboard have always been interested in being able to purchase hard wheat varieties from more local sources,” explains David Marshall, USDA/ARS research leader, who is based at North Carolina State University (NCSU), Raleigh.
The problem has been that developing high-quality hard wheats with the desired disease and pest resistance hasn’t been easy due to the typical high-humidity or rainy conditions of the East Coast. This also causes poor pollination.
“Presently, we aren’t looking at these varieties to go full-scale into the commodity channels,” adds Marshall. “These varieties are intended more for the niche markets, such as organic flours that capitalize on the locally grown appeal.”
Marshall and his team have been working with the North Carolina Organic Bread Flour Project. The project has been examining the qualities of these varieties—grown organically and conventionally. “We’ve approached this breeding program essentially at the grassroots level by trying to get millers and bakers together and seeking their input and involvement as to what they’re looking for in terms of better varieties for the East Coast region,” explains Marshall.
Shown here in Kenya, David Marshall, wheat pathologist and breeder, USDA/ARS, also helps coordinate screening of all United States wheat and barley germplasm for Ug99 stemrust.
Two New Hard Winter Wheat Varieties: NuEast and Appalacian White
When grown in North Carolina, NuEast produced a good, hard red winter wheat quality grain and flour, according to Marshall. NuEast grain and the quality of flour produced from it performed consistently and equally as well as the Hondo, Jagger, and TAM 303 varieties in field trials conducted in Georgia, North Carolina, Kentucky and Virginia. Hondo is an adapted hard red winter wheat variety for the Mid-Atlantic states.
The test weight of Appalachian White in North Caroina was good and the same as Lakin, another popular hard white winter wheat variety. The same was true in other field trials located in Georgia, Kentucky, Virginia, Maryland and Delaware. Appalachian White produced grain with significantly higher hardness scores and significantly higher flour protein levels than Lakin in trials spanning from 2007 to 2009.
Karl Ohm, associate editor, Milling Journal, Second Quarter 2010.
ARS and international cooperators have established the Winter Wheat Stem Rust Resistance Nursery in Ankara, Turkey, to propagate and distribute winter wheat varieties that have been identified as resistant to Ug99.
Read moreabout this research in the February 2010 issue of Agricultural Researchmagazine.
Nursery is New Tool in Fight against Ug99 Wheat Stem Rust
By Stephanie Yao
February 26, 2010
The first Winter Wheat Stem Rust Resistance Nursery, a key tool in the fight against the rust strain Ug99, has been established by the Agricultural Research Service(ARS) and international cooperators.
The nursery, established by ARS and the International Maize and Wheat Improvement Center(CIMMYT), is located in Ankara, Turkey, where CIMMYT coordinates its global winter wheat breeding program. It is the first of its kind for winter wheats, and is a joint effort to distribute 100 lines that have been identified by international scientists as having resistance to the deadly Ug99 stem rust and its descendants.
Thirty of the 100 lines in the nursery were developed by ARS scientists and contain resistance to stem rust races in Kenya and the United States. The lines developed by ARS focus on the use of four or five resistance genes that have been incorporated into various combinations in winter wheat lines.
According to David Marshall, research leader of the ARS Plant Science Research Unitin Raleigh, N.C., and coordinator of the wheat screening conducted in Kenya, multiple genes for resistance will slow the pathogen’s ability to readily overcome the new wheat varieties that breeders develop. The amount of time these genes can remain effective is key to maintaining resistance to stem rust in the United States.
Ug99, Puccinia graminis f. sp. tritici, is the most virulent race of stem rust fungus yet to emerge. First discovered in Uganda in 1999, the fungus has spread across Africa, Asia and the Middle East. Ug99 has been able to overcome most of the stem-rust-resistant wheat varieties developed during the past several decades. While other rusts only partially affect crop yields, Ug99 can wipe out entire wheat fields, resulting in 100 percent crop loss.
Read moreabout this research in the February 2010 issue of Agricultural Researchmagazine.
In Njoro, Kenya, a barley infected with stem rust.
In Njoro, Kenya, a barley that is resistant to stem rust.
The Njoro Research Center of the Kenya Agricultural Research Institute (KARI) has been a hotbed of activity these past few years. Since 2005, plant scientists from research organizations around the world, including the Agricultural Research Service, have been sending their countries’ top wheat cultivars and experimental lines to Njoro for testing against Ug99, Puccinia graminis f. sp. tritici,the most virulent race of the stem rust fungus yet to emerge.
“We have molecular markers that allow us to predict the presence of some resistance genes. But the resistance must be confirmed in the field in Kenya or at other locations where the pathogen exists,” says David Marshall, research leader of the ARS Plant Science Research Unit in Raleigh, North Carolina, and coordinator of the screening conducted at KARI.