New in February, 2014 - Recent Publications, Grants Awarded, Honors and Awards Received, Outreach, Non-technical Articles, Critical and Emerging Issues
Recent Publications -
Norton, G.J., Douglas, A., Lahner, B. Yakubova, E., Guerinot, M.L., Pinson, S.R.M., Tarpley, L., Eizenga, G.C., McGrath, S.P., Zhao, F.-J.,. Islam, M.R., Islam, S., Duan, G., Zhu, Y., Salt, D.E., Meharg, A.A., and Price, A.H. 2014. Genome wide association mapping of grain arsenic, copper, molybdenum and zinc in rice (Oryza sativa L.) grown at four international field sites. PLoS One 9(2): e89685. doi:10.1371/journal.pone.0089685
A number of elements, such as zinc, are required within the human diet, while some elements are toxic to humans, like arsenic. An important first step toward breeding new rice varieties with enhanced grain nutritional value is the identification of genes controlling how much of an element is taken up by the plant from the soil and ultimately accumulated in the grain. In this study, we identified several chromosomal regions containing genes affecting grain concentrations of arsenic, copper, molybdenum and zinc. Of particular interest are six regions known to contain genes affecting metal transporters, factors that control the movement of metal ions through cell membranes.
Li, J., Lu, L., Jia, Y., and Li, C. 2014. Effectiveness and durability of the rice Pi-ta gene in Yunnan province of China. Phytopathology http//dx.doi.org/10.1094/PHYTO-11-13-0302-R
Development of diseases in plants is a result of the interaction of genes in the plant with genes in the pathogen. The AVR-Pita1 gene in the fungus Magnaporthe oryzae, which causes rice blast disease, determines how effective the resistance gene (Pi-ta) is in the rice plant. The goals of this study were to determine the feasibility of the Pi-ta gene for preventing blast disease and to understand the genetic basis of disease susceptibility. Field isolates of the pathogen were collected from several rice production regions in Yunnan province, China. The presence of the AVR-Pita1 was determined in the isolates using molecular markers and methods developed by USDA Agriculture Research Service. Approximately 50 % of the blast isolates contained AVR-Pita1 and were found to be non-infectious to rice plants with Pi-ta. This suggests that Pi-ta is useful in managing blast disease in the rice production areas where blast fungi were isolated. However, changes in the DNA sequence of the protein coding region of AVR-Pita1 in disease-causing isolates demonstrated that genetic changes of blast fungi are the major causes of instability in rice blast resistance.
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Grants Awarded - none to report.
Special invited presentations given, or honors and awards received -
February 18 - ARS scientists, Yulin Jia, Anna McClung, and Georgia Eizenga and NPL, Jack Okumura attended the Rice Blast Symposium in New Orleans, LA . Jia and McClung presented an update on blast resistance research conducted at ARS for the symposium. This was the first symposium funded by a USDA-NIFA project entitled ‘Novel Strategies for Managing Blast Diseases on Rice and Wheat”. There were a total of 54 participants, including representatives from Rice Tec, Inc., Rice Researchers, Inc., DuPont Crop Protection, Syngenta, Mars Foods, Bayer Crop Science, and Rice Technical Solutions, Inc.
February 19-20 - Several of the DBNRRC staff attended the biannual Rice Technical Working Group meeting held in New Orleans, LA which was attended by some 400 rice researchers and stakeholders. The DBNRRC staff made 15 oral presentations and 7 poster presentations in the areas of genetics, grain quality, disease resistance, organic culture, and greenhouse gas emissions mitigation.
February 20 - Dr. Bob Fjellstrom, DBNRRC Molecular Geneticist, was presented with the Distinguished Service Award by his peers at the Rice Technical Working Group meeting held in New Orleans, LA for his research which has facilitated the adoption of molecular markers for use in breeding by public and private US research programs.
February 20, - Dr. Ming-Hsuan Chen, DBNRRC Research Chemist, was elected to be the next panel chair for the Processing, Storage and Quality area for RTWG 2016.
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Public Outreach/Stakeholder and Collaborator Contacts -
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February 7 – Several of the DBNRRC staff met with three educators from the University of Arkansas at Stuttgart community college to discuss plans for DBNRRC staff to serve as mentors and tutors for new college students in the area of science and math.
February 10 - Dr. David Gealy consulted with Mason Wallace, RiceTec, Inc., Harrisburg, AR, and provided seed of several US red rice cultivars from the USDA-ARS GRIN collection for use in hybrid rice research.
February 11 - Drs. Anna McClung and David Gealy gave presentations at a meeting with some 25 Arkansas rice growers that have interest in organic rice production. The meeting was organized by Stephen Hilsdon, Specialty Rice, Inc., Brinkley, AR which markets organic and aromatic rice in the US.
February 13 - Dr. Brett Savory, Dr. Jay Xu and graduate student Ningning Zhang, all of Arkansas State University, Jonesboro, visited with Drs. Anna McClung and Ming-Hsuan Chen to discuss research plans for the recently funded USDA-AFRI grant “Establishing the function and availability of bioactive components from whole-grain rice varieties for colon-specific health benefits."
February 14 - Dr. David Gealy consulted with Scot Aker, US National Arboretum, Washington, DC regarding use of new weed-suppressive rice germplasm in a future display of ‘agronomic grasses’ at the Arboretum.
February 18 - Drs. Georgia Eizenga and Anna McClung participated in the annual Rice Crop Germplasm Committee meeting held at New Orleans, LA. The purpose of the committee is to serve as a liaison between the research community and the National Plant Germplasm System. Discussions included an overview of the Rice Diversity Panel 2 (RDP2), developed by IRRI, which consists of 1,311 global rice accessions which have been genotyped with some 300,000 SNP markers. The RDP2 is currently being brought through quarantine as a result of a collaboration between ARS, APHIS, and university researchers. Over the last two years, ARS, APHIS, and the University of Arkansas have successfully brought through quarantine the Brazilian rice core collection. The possible introduction of an additional 3,000 global accessions being re-sequenced in China was also discussed. Other topics included a request to APHIS to import large quantities of rice seed from Argentina and the fact that the PVP office is now allowing marker data to document the uniqueness of new varieties. The DBNRRC efforts to continue to “fill-in” missing descriptor information on rice accessions in GRIN was commended by the panel.
February 19 - Dr. David Gealy consulted with Dr. Reid Smeda, University of Missouri, Columbia, MO, and provided seed of several US red rice cultivars from the USDA-ARS GRIN collection for use in rice allelopathy research.
February 20 - Dr. Yulin Jia consulted with Dr. Kirk Johnson, Hybrid Rice Breeding Manager, and Dr. Qiming Shao, Hybrid Rice Breeder, of Bayer Crop Sciences, El Campo, TX, and provided them with 20 rice cultivars from the USDA core collection with the molecular markers tagging two major resistance genes to rice blast disease.
February 23 - Dr. David Gealy provided panicles of rice to Gina Gorman at Ferguson & Katzman Inc., St. Louis, MO, to be used in a photo-shoot for pet food advertisements.
February 24 - Drs. Ming-Hsuan Chen, Rolfe Bryant, and Anna McClung met with Eric Jackson of General Mills to discuss the potential for utilizing genomic data for grain quality assessment in rice.
February 27 - Drs. Rolfe Bryant and Anna McClung discussed with Joe Kepiro of Rice Researchers, Inc., Glenn, CA, analytical methods to assess rice cooking quality.
February 28 - Dr. David Gealy provided information on carbon-12:carbon-13 isotope ratios in rice to Dr. Michael Trinkley, Chicora Foundation, Columbia, SC, for use in dietary analysis evaluation of historic human skeletal remains.
Non-technical Articles Published - none to report
Critical or Emerging Issues
A fungicide resistant form of the pathogen Rhizoctonia solani, which causes sheath blight disease in rice (and many other diseases in other crops) was found in a few Louisiana rice fields a couple of years ago. Since then it has spread some 20 miles from the original site. The resistance is due to a mutation that has occurred in the pathogen. However, other fungicides are available that attack a different pathway in the fungus.
Rice millers indicate that the number one complaint concerning US rice in the export market is due to high levels of chalk in the milled grain. Other concerns include shorter than desired grain length and grain fissuring that occurs during shipping.
Researchers from Mississippi report that in 2014 five percent of all agricultural irrigation wells will be required to be metered in an effort to reduce water usage. Forty percent of the Mississippi alluvial aquifer is now showing signs of depletion.
Arkansas is 4th in the US in irrigated acreage and 2nd in the nation in the volume of water applied, largely due to rice production. Eighty percent of this water comes from underground aquifers.
Most rice producing states are predicting an increase in acreage for rice production in 2014 as a result of declining prices for corn. However, Texas and California are currently experiencing drought conditions and acreage is not expected to increase in these states.
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For more information, please contact Anna McClung, Research Leader, email@example.com.