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Mark Williams

Mark Williams
220 Ag Quad Lane
301 Latham Hall
Blacksburg, VA 24060


Dr. Williams's research is focused on understanding how microbial communities assemble and function in ecosystems, soil, the root-zone, and other numerous habitats found in nature (e.g. honeybee gut). His studies reflect on the mutualistic nature of plant-microbial feedbacks that are a major driver of ecosystems and the global biosphere. 

Using next-gen sequencing, LC and GC- mass spectrometry, and tried and true plant, microbial, and soil techniques his lab answers questions about the distribution and function of microbial communities from the scale of the root-zone to the biogeochemical cycles of earth. The lab studies native, remnant and human-managed ecosystems.

Research Interests

  • Microbial ecology
  • Plant growth promotion
  • Rhizobium spp.
  • Mycorrhizae 
  • Land management
  • Natural ecosystems

Current And Evolving Projects

  • Developing a new plant-microbial breeding platformVirginia Soybean Board, Submitted to NSF.
  • Assessing the potential for nitrogen fixation bacteria to supply agronomically signficant amounts of N to maize.   Submitted to Virginia Corn Board
  • Microbial functional changes and soil protein accrual during soil pedogenesis. USDA-NIFA, Microbial communities in soil, air, and water. 
  • Using a microbiome approach to reducing the resistome in poultry litter amended soils.  USDA-NIFA.  
  • Alternative fertilizer recommendations that support helper soil microbial communities in high-density apple orchards  USDA-Sustainabale Agricutural Research and Education Program and Virginia Dep of Agricutlural Resarch and Consumer Services Collaborator Greg Peck, Cornell University

Completed Projects

  • Microbial community responses to water stress in soil. USDA-NRI
  • Impact of agricultural land management on microbial communities. USDA-NRI
  • N-fixation associated with feedstock grasses. DOE
  • Microbial community change during vegetative succession and soil-ecosystem development. National Science Foundation
  • Developing sustainable plant-microbial interactomes to feed an impoverished world: exploiting gene diversity for Fe and Zn accumulation in tubers of potato and its interaction with helper microbes. Gates Foundation and Institute for Critical Technologies and Applied Sciences Based Spectroscopy. National Science Foundation
  • Fall, Soil Microbiology 4064/5064G
  • Spring, Ecology of Plant-Microbial Interactions  5914