Metabolic Engineering to Improve Sustainability of Agriculture
Agricultural crop production is facing many challenges – now and in the future. An anticipated increase in the demand for food and feed under changing climate conditions requires improvements to quality and quantity of production. Our research aims to understand the molecular mechanisms responsible for plant responses to nutrient limitations of nitrogen, phosphate and water. To improve sustainability of agricultural crop production, we have engineered new pathways into plants that improve their efficiency in photosynthetic CO2 fixation, reduce energy and carbon losses, and increase their nutrient use efficiency.
Metabolic Engineering to Increase Oil Seed Crop Yield
Camelina sativa is an excellent oil crop for feed and biofuel production because it grows with little water and fertilizer on marginal land. To improve camelina as a dedicated biofuel plant, we have increased its photosynthetic CO2-fixation rates by modifying CO2 transport, assimilation and allocation and reducing the cost of photorespiraton. To extend its agricultural range, we are improving its stress tolerance against heat and drought.
We are currently working on new technologies to modify the plastid genome and regenerate homoplasmic crops. This technology will enable the generation of crops with better pest-resistance and provide a platform for the fast and safe production of biopharmaceuticals.
Re-engineering Arbuscular Mycorrhizal Symbiosis Brassicaeceae
Plants have evolved to optimize growth and survival in their physical (abiotic) and biological (biotic) environment. An important interaction is the ability to build symbiotic relationships with fungi and bacteria that enable them to access essential nutrients like nitrogen, phosphate and water beyond the reach or ability of their roots. A symbiotic relationship has evolved between plant roots and specific fungi (e.g. Rhizophagus irregularis) which invade and form Arbuscular Mycorrhizae (AM). These fungal hyphae are thinner than plant roots and can therefore access nutrients and especially immobile phosphate in the soil in spaces the plant root cannot reach. AM fungi establishes an intracellular membrane system within host cells that enables the exchange of sugar and lipids from the plant for nutrients and water from the fungus. The great majority (~95%) of plant species on Earth form AM whereas, the agriculturally important Brassicaceae (e.g. rapeseed, mustards, cauliflower, cabbage) and Amaranthaceae (e.g. spinach, beets, quinoa) have lost the ability to establish this type of symbiosis with fungi. We have carried out comparative genome analysis of known symbiosis pathway elements and are transforming the “lost genes” into Camelina in an attempt to re-establish their ability to host AM.
Bigger and Better Sweet Potatoes
Sweet potato is ranked by the Food and Agricultural Organization (FAO) as the seventh most important food crop in the world (FAO, 2013). In Ghana, sweet potato has been ranked as the fourth most important crop. The crop is a rich source of important nutrients including beta carotene, and this makes sweet potato an important crop to alleviate malnutrition and vitamin A deficiency in the developing countries. North Carolina is the No.1 sweet potato producing US State and NCSU has the largest breeding project in the US. We are developing gene-editing technologies for sweet potato to further increase its yield and nutritional content.
- BIT 476/576 Applied Bioinformatics
- PB 751 Advanced Plant Physiology (Spring)
- PB 495/595 Innovation in Agricultural Biotechnology (Fall)
Ph.D. Biochemistry University of Goettingen, Germany 1993
M.S. Biochemistry University of Goettingen, Germany 1990
Area(s) of Expertise
Plant Physiology and Metabolic Engineering
- Gene sdaB Is Involved in the Nematocidal Activity of Enterobacter ludwigii AA4 Against the Pine Wood Nematode Bursaphelenchus xylophilus , FRONTIERS IN MICROBIOLOGY (2022)
- Organic solar powered greenhouse performance optimization and global economic opportunity , ENERGY & ENVIRONMENTAL SCIENCE (2022)
- An Overview of the Practices and Management Methods for Enhancing Seed Production in Conifer Plantations for Commercial Use , HORTICULTURAE (2021)
- Balancing crop production and energy harvesting in organic solar-powered greenhouses , CELL REPORTS PHYSICAL SCIENCE (2021)
- Epigenetic modification associated with climate regulates betulin biosynthesis in birch , JOURNAL OF FORESTRY RESEARCH (2021)
- Achieving Net Zero Energy Greenhouses by Integrating Semitransparent Organic Solar Cells , JOULE (2020)
- Microbial Interactions Within Multiple-Strain Biological Control Agents Impact Soil-Borne Plant Disease , FRONTIERS IN MICROBIOLOGY (2020)
- Qu-2, a robust poplar suspension cell line for molecular biology , JOURNAL OF FORESTRY RESEARCH (2020)
- One thousand plant transcriptomes and the phylogenomics of green plants , NATURE (2019)
- Relating nitrogen concentration and light intensity to the growth and lipid accumulation of Dunaliella viridis in a photobioreactor , Journal of Applied Phycology (2019)
One of the grand challenges facing humanity is to secure sufficient and healthy food for the increasing world population. This requires maintaining sustainable cultivation of crop plants under changing climate conditions. Plant roots and soil microbes have been associated since the emergence of plants on land. Nevertheless, the mechanisms that coevolved to control and regulate microbiota associations with healthy plants are largely unexplored. The photosynthetically active green leaf tissues supply assimilated carbon to roots for development and also to feed its associated microbes. To maintain balanced growth, plants have to integrate this underground demand and regulate the rate of photosynthetic CO2 fixation, and sugar allocation needs to be coordinated between root and shoot. Research on plants and their naturally associated microorganisms is therefore in a prime position to provide new perspectives and concepts for understanding plant function, plant performance and plant growth under limited input conditions with a reduced environmental footprint and could also define breeding targets and develop microbial interventions. InRoot aims to: 1. Disentangle the effects of climate and soil type from the impact of root-microbe interactions through transplantation experiments and exploit natural variation to identify the plant genetic components responsible for adaptation to the local microbiota. 2. Identify key bacterial taxa governing the establishment of host-driven microbial networks in the rhizosphere by analysing the microbe-microbe and microbe-host interactions established in tailored synthetic communities (SynComs) with direct consequences on host performance. 3. Define the plant genetic components that control infection of plant roots by ubiquitous and host-specific endophytes using advanced genetic screens and new methods for quantifying root cellular responses to microbes 4. Understand molecular mechanisms integrating root-microbe interactions into whole-plant physiology by investigating systemic physiological responses induced by SynComs using whole plant phenotyping. 5. Predict plant performance as a function of plant and microbiota genotypes by building multiscale models based on genotype, phenotype, and mechanistic data thereby providing knowledge for application. InRoot perspective: Provide knowledge and tools for science-based development of new crop varieties and associated microbial interventions that will improve productivity, reduce the need for fertilizers and pesticides, and alleviate negative environmental impact.
Challenges at the FEW nexus are not simply technological, but convergent in the sense of spanning technical, ecological, social, political, and ethical issues. The field of biotechnology is evolving rapidly - and with it, the potential for creating a diverse array of powerful future products that could intentionally and unintentionally impact FEW systems. Depending on what products are developed and how those products are deployed, biotechnology could have a positive or negative impact on all 3 of these systems. Wise decisions will require leaders who can integrate knowledge from engineering, design, natural sciences, and social sciences. We will train STEM graduate students to respond to these challenges by conducting convergent research aimed at development, and assessment of biotechnologies to improve services provided by FEW systems. We will train our students to engage with non-scientists to elevate societal discourse about biotechnology. We will recruit 3 cohorts with emphasis on students who have shown a passion for crossing between natural and social sciences. We will work with the NCSU Initiative for Maximizing Student Diversity in recruiting students from underrepresented minority groups. Cohorts will have 6 students who will take a minor in Genetic Engineering and Society (GES). They will receive PhDs in established graduate programs such as Plant Biol, Chem & Biomol Engr, Econ, Public Adm, Entomol, Plant Path, Communication, Rhetoric & Digital Media, Forestry & Environ Res, Crop & Soil Sci, and Genetics. For students in natural science PhD programs, at least 1 thesis committee member will be from a social sciences program and vice versa for students in social sciences. For all students, at least 1 thesis chapter will demonstrate scholarship across natural and social sciences. The disciplinary breadth of our proposed NRT is very broad, so we will focus student projects narrowly on a specific biotechnology product that impact FEW systems. When they first arrive at NCSU, cohorts will participate in a training program off campus where they will be exposed to the issues they will address. Students will carry out a group project in the focus area of the cohort to continue team development. To fulfill the GES minor, students will take 3 specially designed courses: Plant Genetics & Physiology, Science Communication & Engagement, Policy & Systems Modeling. There are no NRT-eligible institutions partnering on this project outside of an evaluation role.
The NCSU Phytotron is a premier growth facility that serves the NCSU community, as well as other NC academic institutions and NC companies of various sizes. The Phytotron has always maintained a high-level of precision in regulating environmental conditions. The facility is now more than 50 years old and after many years of heavy use, it has required major renovations and upgrades to keep up with research needs. We were able to conduct an extensive energy conservation project with the NCSU Facilities group to upgrade the growth chambers, as well as the heating, cooling and electrical systems of the Phytotron. During the renovation process we lost precision in controlling the environmental variables of the Phytotron greenhouses. Facilities with a high level of precision in environmental control are necessary for securing research funds, conducting repeatable experiments and enhance graduate student performance. We seek to install a state-of-the-art control system that can be used to not only allow us to precisely control the environmental conditions of the greenhouses but would also increase our capabilities including use of the specialized moisture sensing and weighing system that was donated by Syngenta to the NCSU Horticultural Science Department and requires an Argus system to function. The Argus system that we are requesting would provide state-of-the-art environmental control that is not currently available in any of other plant growth areas at NCSU and would provide the Phytotron with a system similar to the ones used at state-of-the-art growth facilities in RTP. It would also allow connectivity between the Phytotron and the new Plant Sciences building that is being constructed on NCSUÃƒÂ¢Ã¢â€šÂ¬Ã¢â€žÂ¢s Centennial Campus.
The objective of this research is to develop semi-transparent organic solar modules integrated with greenhouses along with engineered plant photo-action spectra that synergistically provide food and energy sources while conserving water for a new food-energy-water paradigm.
The United States Agency for International Development (USAID), in partnership with the Association of Public and Land-grant Universities (APLU) and the International Maize and Wheat Improvement Center (CIMMYT) in Mexico, selected Michigan State University (MSU) to implement the Feed the Future Borlaug Higher Education for Agricultural Research and Development (BHEARD) Program. The goal of this project is to increase the number of agricultural scientists working in the developing world and to strengthen scientific institutions in developing countries. To do this, the BHEARD program plans support long-term training of agricultural researchers at the masterÃƒÂ¢Ã¢â€šÂ¬Ã¢â€žÂ¢s and doctoral levels through linkages in the scientific and higher education communities in Feed the Future countries and the United States. During Fall 2015 a BHEARD Expression of Interest was sent to APLU members to solicit mentors for students selected for this program. Drs. Yencho and Sederoff were selected as a good match for Mr. Samuel Acheampong, who is interested in working in sweetpotato biotechnology. Yencho and Sederoff are working with Jose Cisneros, Director of CALS International Programs to implement this training.