The species of yeasts that colonize floral nectar face two major challenges: high osmotic pressure caused by excessive carbon supply and strong resource competition caused by low nitrogen availability. This project is aimed at identifying the genes and pathways that enable nectar yeasts to grow in the carbon- and nitrogen-stressed environment. Nectar yeasts have presumably…
Gene Atlases of Grass-Microbe Interactions
Grasses comprise key food crops, as well as bioenergy feedstock. However, their productivity and biomass is greatly hindered by viral, fungal, and bacterial infections, which cause yield losses of up to 60 percent. This proposal seeks to build comprehensive gene atlas maps for diverse bioenergy grass-microbe interactions, including pathogenic and beneficial interactions in two grass…
Shaping the Brachypodium Polyploid Model
Polyploid plants are often larger than their diploid progenitors and can be more stress tolerant. Some of the world’s most important crops are polyploid. This project uses three small grasses with compact genomes and traits that make them easy to manipulate in the laboratory. Brachypodium hybridum is an allotetraploid formed by interspecifc hybridization between the…
Improving Crop Productivity Strategies
The sustainable production of biofuels from energy crops could greatly benefit from strategies that increase crop productivity in existing agricultural lands. Application of rare earth enzymes (REE) increases crop yields but the molecular mechanisms by which REE increase plant productivity are not well understood. As REE affect the metabolism of methylotrophs, a predominant member of…
Impact of Plant Cell Wall Modification
ORNL researchers are testing the hypothesis that genetic modification of plant cell wall has cascading and quantifiable impacts on its secondary metabolome and the associated functional microbiome. The hypothesis is based on the team’s recent finding that modification of a plant cell wall pathway gene, PdKOR, an endoglucanase, in Populus can impact its ability to…
Phenomics of the Model Alga Chlamydomonas reinhardtii
Heat stress impairs plant growth and reduces crop yield. In nature, temperature and day length are linked together; longer days tend to have higher temperatures than shorter days. Little is known about how photosynthetic organisms regulate and integrate their responses to high temperature and day length to optimize growth. The team will use green alga…
Metabolic Diversity of Sorghum and Maize
Leveraging genetic and biochemical approaches with JGI contributions, researchers aim to better understand the metabolic diversity of sorghum and maize, how that metabolic diversity is generated, and how specific metabolites and pathways mediate plant interactions with the microbial community. Together these resources and knowledge are anticipated to guide development of next generation Poaceous fuel crops…
Molecular Mechanisms of Parasitic Chytrids
Chytrids hinder algal biofuel cultivation by causing population crashes, but little is understood about how and under what conditions chytrids infect algae. Recently, researchers have found that the chytrid Paraphysoderma sedebokerense is a facultative algal parasite of Haematococcus pluvialis, whose trophic strategy is regulated by dissolved organic carbon availability. The molecular changes underlying its switch…
Bacteria and Fungi in Native Prairies
Despite the persistent presence of potentially harmful fungi and bacteria, America’s native prairies are healthy, thriving communities of perennial herbaceous plants. How do these communities maintain a balance with these microbes? Bacteria and fungi found in native prairie soil, are mutually antagonist and thus may keep each other in check. Each produces antibiotic compounds when…
Dynamics of Wetland Mangrove Ecosystems
Wetland mangroves are among the most productive ecosystems on the planet, generating a substantial amount of methane each year. Researchers know very little about how the microbial communities responsible for methanogenesis respond to climatic shifts. Since these communities experience strong subtropical seasonal and diurnal changes in light and temperature, the team aims to track temporal…