• Betsy Arnold (UA, Plant Sciences and Ecology & Evolutionary Biology)
  • Rachel Gallery (UA, Natural Resources and the Environment)
  • David Baltrus (UA, Plant Sciences)
  • Eric Lyons (UA, Plant Sciences)


One of the most profound insights of the past century is that no macroscopic organism exists in nature in the absence of microbes. Numbering far beyond the subset that cause disease, the diverse assemblage of microorganisms that occur within, around, and upon macroscopic organisms – that is, their microbiome — shapes all aspects of human health and sustainability. Microbiomes influence processes as diverse as our development and digestion, the nutritive enhancement and release of our food, the uptake of water by our crop plants, and the protection of diverse organisms against abiotic stress, aging, and disease. Among the most accessible and important microbiomes are those associated with plants – the bacteria, fungi, archaea, protists, and viruses that occur in plant tissues, on plant surfaces, and in soil. These diverse and often beneficial microbial communities represent genetic, taxonomic, and functional resources for crop improvement that are unmatched in terms of transformative potential. Wide-spread evidence points to the importance of plant microbiomes in influencing plant productivity, protecting plants against environmental stresses, and transferring phenotypic traits — such as drought-, salinity-, or heat tolerance – rapidly and reliably from one host plant to another. Recent advances in microbial ecology highlight the global uniqueness of Arizona’s plant-microbiome resources, and leaps forward in technology now permit the rapid discovery and application of these resources in innovative ways. As a diverse group of faculty in the College of Agriculture and Life Science at the University of Arizona we share common interests in discovering and translating arid-land plant microbiomes. Our collaboration brings together microbiology, genomics, biotechnology, crop science, nutritional science, bioengineering, plant ecology, and bioinformatics.