Emeritus Research Professor
University of Missouri Research Reactor and Department of Chemistry
Biochemistry, Environmental Interactions, Plant Physiology,
Research
Building an Integrative Imaging Platform in Plant Science A Grand Challenge in Sustainable Cropping
Agriculture in the 21st century faces formidable challenges: on the one hand, it has to produce more food and fiber to feed a growing population, while on the other it has to increase biomass feedstocks for an increasing bioenergy and chemical commodities market. Projections show that feeding a world population of 9.1 billion people in 2050 will require raising overall food production by more than 50 percent. Production in developing countries will need to almost double. To meet the rising challenge in global food security alone, agriculture will need to adopt more efficient and sustainable crop management practices that will enable farmers to produce higher yields from the same acreage of arable land. Amidst this global agricultural crisis, farmers are also facing many other challenges that can severely impact daily crop performance. For example, plant stress and underperformance can manifest from a number of environmental influences including; nutrient starvation due to lack of inputs or competition belowground with the microbiome, extreme changes in climatic conditions (e.g. heat, cold, drought, flooding), and predatory attack by herbivores.
The relationship between plants, microbes and their surrounding environment is highly complex since each can exert an influence on the other. For example, the exchange of carbon and nitrogen resources between plants and the soil microbiome can accelerate plant root development, thereby providing plants with better access to nutrients and water and reducing the need for irrigation and soil amendments. These relationships can also help mitigate plant stress to climatic extremes. Understanding these relationships is not only critical to stabilizing our future global food securities, but is also critical to improving our environment through improved terrestrial carbon cycling, and/or the development and management of renewable energy resources that could offset global reliance on fossil fuels.
Furthermore, the relationships and chemical dynamics responsible for the flow of information and materials that occurs at the interface between plants and microbes and their environment can encompass enormous spatial and temporal scales. Their exploration and integration from subcellular through to whole ecosystem levels requires a multitude of imaging technologies.
Accordingly, my vision to establish a multidisciplinary imaging platform that will integrate radiochemical imaging technologies including PET and SPECT with mass spectrometric imaging (MSI) technologies including NanoSIMS, MALDI MS and LA-ICP-MS. When utilized in concert, researchers will be uniquely positioned to examine the exchange of plant resources, including metabolites, hormones and inorganic ions both at the root-soil interface and between the plant root and shoot systems. Key advantages of utilizing PET and SPECT imaging is that they can provide dynamic information on resource exchange non-destructively and repeatedly in the same organism enabling researchers to examine changes of physiological responses across scales of time as a function of treatment or as a function of the plant’s natural development. However, these instruments track the movement of the radioactive isotopes, and hence do not provide identifying information on the nature of the substrates to which they are bound. Mass spectrometric imaging (MSI) is a developing research technology applied first for biomedical problems; it is now being adopted by plant biologists to measure the distribution of a wide variety of biomolecules in plant tissues. Spatially resolved chemical structural information (at a spatial resolution of 10-15 µm) revealed through MSI is directly relevant to the elucidation of regulation, function and allelic variation of plant genes controlling biomolecule synthesis, enabling the development of molecular markers for plant breeding. MSI is being used for numerous plant biology studies, including biosynthesis of natural products and metabolites in specialized groups of cells, mechanisms of response to biotic and abiotic stresses, plant microbe interactions, N2 fixation and nutrient cycling. We expect that MS imaging technologies using stable isotope tagging will complement the dynamic radiochemical imaging technologies by providing high resolution snapshots with chemical identifying information. Taken together, these tools will provide a deeper understanding of the chemical and biological mechanisms and interactions among the root, rhizosphere, and soil microorganisms and the impacts these have on the entire plant that will be the targets of plant breeding for crops with more active and vigorous root systems that are more efficient at capturing and acquiring water and mineral nutrients.
The Critical Role of Chemistry in this Challenge:
Imaging technologies enabling visualization of dynamic intracellular processes, as well as functional characterization from subcellular to cellular scales will rely heavily on spectroscopic methods, stable isotopic labeling, isotope production and radiochemistry. Success here will be determined by the willingness and determination of chemists to design and synthesize unique molecular probes suitable for use with this instrumentation.
Broader Impact: Through the integration of imaging technologies that will be supported by my research initiative, researchers in agriculture will be uniquely positioned to leverage an array of powerful technologies for spatially and temporally resolving biological functions across multiple scales of life. Ultimately, the biological data that comes out of this effort will provide new insights on mechanisms for crop tolerance and sustainability that can aid breeders in marker assisted selection, geneticist in engineering metabolism, or alternate `green farming’ strategies that rely on growth promoting rhizobacteria. In the end, my goal is to provide the imaging tools for guiding the next generation of feedstocks serving both agriculture and energy needs worldwide.
Awards & Honors
- Senior Research Faculty Professor, MURR (June 2016)
- Director, DOE Radiochemistry SFA Program (June 2014-2016)
- Co-PI Director, DOE Mesoscale Project (April 2014-present)
- U. Missouri NSF EPSCor Program Advisory Committee (2013-present)
- Adjunct Faculty, University Missouri (Columbia), Chemistry Department, 2009-present
- Secretary, BNL Council (2013-2015) BNL Life Sciences Quality Assurance Committee Chair (2006-2012)
- Adjunct Faculty Montclair State University, Environmental Sciences, (2011-2014)
- Scientist with Tenure, Brookhaven National Laboratory, 2009
- Site Director, DOE Nuclear and Radiochemisty Summer School, 2006-2011
- Chair, Life Science Quality Assurance Committee, 2007-2008
- Chair, BNL Institutional Review Board, 2007
- Deputy Chair, BNL Institutional Review Board, 2001-2006
- Supervisor of Operations, BNL PET Radiotracer Laboratory, 1994 - 2006
- Chemist (BNL Scientific staff with continuing appt.), 1988
- Visiting Scientist, Chemistry Dept., UC Berkeley1986-1987
- Associate Chemist, Chemistry Dept., BNL, 1983-1986
- Assistant Chemist, Chemistry Dept., BNL, 1981-1982
