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United States Department of Agriculture

Agricultural Research Service

Donald Ort Lab
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Research Overview . Lab Personnel . Select Publications

Research Overview

The long range goal of my esearch program is to define how the component processes of photosynthesis integrate to determine photosynthetic performance under agronomically significant situations. With a small vigorous group of research associates and graduate students my lab will focus on the following specific goals over the next 5 years: Donald Ort

  • Over the past two decades, my research interests have focused on the effect that specific environmental factors and abiotic stresses have on the photosynthetic performance of crop plants. Currently my research team of post-doctoral associates and predoctoral graduate students are investigating the molecular and biochemical bases of the chilling sensitivity of warm climate crops and the interactions of crop plant photosynthesis with the rapid changes that are occurring in the atmosphere.

    Cool temperatures and warm climate crops. Many important agronomic species grown in temperate climates have been imported from warmer tropical and subtropical habitats (e.g., corn, soybean, cotton, tomato). Unlike native temperate climate species, most plants from warm climate evolutionary origins have very little capacity to acclimate to cool much less freezing temperatures. Because the cool temperature sensitivity of these crops plays a central role in determining the growing range as well as annual variations in their economic success, there is intense interest in discovering the mechanistic bases for low temperature sensitivity. It is hoped that by defining the primary chilling-induced lesions that cause the metabolic dysfunctions in warm climate plants that it will be possible to devise strategies to minimize the sensitivity. However, the relevant physiological bases of chilling sensitivity depends critically on the seasonal climatic conditions of the target growing region, whether the low temperature episodes occur at night or in the light, as well as on the species of warm climate plant under consideration. These issues are considered in devising a research strategy to understand the underlying mechanisms of chilling sensitivity.

    Impacts of increasing atmospheric carbon dioxide and tropospheric ozone on photosynthesis and productivity of soybean and corn. Corn-Soybean is the largest ecosystem in the US, dominating the Midwest. SoyFACE ( a unique open-air laboratory that uses fast-feedback control technology to treat large fully replicated areas with future carbon dioxide, ozone, and soil moisture. Multi-user training and research on topics from soil microbes and gene expression to regional economies, C-cycle and atmosphere. We are investigating the effects of atmospheric change on photosynthesis and canopy energy balance, as well as the interaction of increased atmospheric CO2 and drought.

    Genomic Ecology of Global Change. How ecosystems will respond to rapid changes in climate represents one of the great scientific challenges of this century. Human activities are altering the composition of our atmosphere (carbon dioxide and ozone), affecting the Earth’s climate system (elevated temperature and water deficits) and introducing invasive species, thus altering the capacity of native and agro-ecosystems to provide critical goods and services including food, fiber, fuel, clean air and water. Though the phenomenology of ecosystem responses to elements of global change is receiving considerable attention, it has been predominantly limited to descriptive research at the level of the individual. The U of I has established the only facility worldwide for studying the simultaneous effects of rising carbon dioxide, ozone, and drought on plants under completely open-air conditions. We are therefore in a unique position to establish an internationally unique research program to examine the effects of global atmospheric change on the transcriptome and proteome of agro-ecosystems. The aim of the Genomic Ecology of Global Change theme within the Institute of Genomic Biology is to produce the scientific foundation to use information obtainable at the level of genomes and proteomes of species and communities to predict the effect of environmental changes on the structure and function of ecosystems. Mathematical modeling and bioinformatics provide the conceptual foundation and data analysis tools for making sound scientific inference. To achieve this aim we have assembled an interdisciplinary team of eight faculty spanning molecular to ecological research, within an overarching link of mathematical modeling and informatics.


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Lab Personnel

Kevin Hollis Graduate Student
Ping Gong Graduate Student
Elie Schwartz

Graduate Student

Andrew Leakey Research Associate
Aleel Grennan Assistant to the Editor

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Select Publications

  1. Hutchison RS, Groom Q, Ort DR (2000) Differential effects of chilling-induced photooxidation on the redox regulation of photosynthetic enzymes. Biochemistry 39, 6679-6688
  2. Singsaas E, Ort DR, DeLucia E (2000) Variation in measured values of photosynthetic quantum yield in ecophysiological studies. Oecologia 128, 15-23 Ort DR (2001) When there is too much light. Plant Physiol. 125, 29-32
  3. Allen DJ, Ort DR (2001) Impacts of chilling temperatures on photosynthesis in warm-climate crops. Trends Plant Sci 6, 36-42
  4. Ort DR (2002) Chilling-induced limitations on photosynthesis in warm climate plants: Contrasting mechanisms. Environ Control Biol. 40, 7-18
  5. Tucker DE, Ort DR (2002) Low temperature induces expression of nitrate reductase in tomato that temporarily overrides circadian regulation of activity. Photosynth Res: 72: 285-293
  6. Ort DR, Baker NR (2002) Photoprotection: The role of electron sinks. Curr Opin Plant Biol 5: 193-198
  7. Ort D.R. and Long S.P. (2003) Converting Solar Energy into Crop Production. (eds M.J. Chrispeels and D.E. Sadava), pp. 240-269. American Society of Plant Biologists/Jones and Bartlett, Boston
  8. Ort DR (2003) Contrasting mechanisms responsible for chilling-induced inhibition of photosynthesis in warm climate crops. Indian J Plant Physiol 2003 (Special Issue), 1-10
  9. Singsaas E, Ort DR, DeLucia E (2004) Elevated CO2 effects on mesophyll conductance and its consequences for interpreting photosynthetic physiology. Plant Cell Environ 27, 41-50
  10. Tucker DE, Allen DJ, Ort DR (2004) Control of nitrate reductase circadian and diurnal rhythms in tomato. Planta, 219, 277-285
  11. Rogers A, Allen DJ, Davey PA, Morgan PB, Ainsworth EA, Bernacchi CJ, Cornic G, Dermody O, Heaton A, Mahoney J, Zhu X-H, DeLucia E, Ort DR, Long SP (2004) Leaf photosynthesis and carbohydrate dynamics of soybeans grown throughout their life-cycle under Free-Air Carbon dioxide Enrichment. Plant Cell Environ. 27, 449-458
  12. Schrader SM, Wise RR, Wacholtz WF, Ort DR, Sharkey TD (2004) High leaf temperature limits photosynthesis in Pima cotton II. Thylakoid membrane responses to moderate heat stress. Plant Cell Environ 27, 725-7351
  13. Leakey ADB. Bernacchi CJ, Dohleman FG, Long SP, Ort DR (2004) Will photosynthesis of maize (Zea mays) in the U.S. Corn Belt increase in future [CO2] rich atmospheres? An analysis of diurnal courses of CO2 uptake under Free-Air Concentration Enrichment (FACE). Global Change Biol. 10, 951-962
  14. Long SP, Ainsworth EA, Rogers A, Ort DR (2004) Rising Atmospheric Carbon Dioxide: Plants FACE the future. Annual Reviews Plant Biol. 55, 591-628
  15. Baker NR, Ort DR, Harbinson J, Whitmarsh, J (2004) Light processing: Chloroplats to leaf. In Photosynthetic Adaptation Chloroplast to Landscape (Smith WK, Vogelman TC, Critchley, C, eds) Springer, pp 89-104
  16. Loreto F, Baker NR, Ort DR (2004) Environmental constraints: Chloroplast to leaf. In: Photosynthetic Adaptation Chloroplast to Landscape (Smith WK, Vogelman TC, Critchley, C, eds) Springer, pp 231-261
  17. Zhu X-G, Ort DR, Whitmarsh J, Long SP (2004) The slow reversibility of photosystem II thermal energy dissipation on transfer from high to low light may cause large losses in carbon gain by crop canopies. A theoretical analysis. J Exp Bot, 55, 1167-1175
  18. Morgan PB, Bernacchi CJ, Ort DR, Long SP (2004) An in vivo analysis of the effect of season-long open-air elevation of ozone to anticipated 2050 levels on photosynthesis in soybean. Plant Physiol 135, 2348-2357
  19. Bernacchi CJ, Morgan PB, Long SP, Ort DR (2005) The growth of soybean under free air concentration enrichment (FACE) stimulates photosynthesis while decreasing apparent in vivo Rubisco capacity. Planta 220, 434-446
  20. Zuniga-Feest A, Ort DR, Gutierrezc A, Gidekel M, Bravo LA, Corcuera JL (2005) regulation of sucrose-phosphate synthase acitivity in the grass Deschampsia antarctica. Photosyn Res 83,75-86
  21. Long SP, Zhu X-G, Naidu SL, Raines CA, Ort DR (2005) Limits on the efficiencies of primary production - constraints and opportunities. In: Yields of farmed species: Constrains and opportunities in the 21st century. Eds. Sylvester Bradley R, Wiseman, J. Nottingham University Press (In press)
  22. Zhu X-G, Govindjee, Baker NR, De Sturler E, Ort DR, Long SP (2005) Chlorophyll a fluorescence induction kinetics in leaves predicited from a model describing each discrete step of excitation energy and electron transfer associated with photosystem II. Planta (in press)

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For additional information, please visit Dr. Ort's other lab page.

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Last Modified: 12/24/2008
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