Research

Rewilding Microbiomes And Rootstocks Towards Nitrogen-Smart Hemp Production Practices

Hemp (Cannabis sativa L.) is a versatile alternative crop that can help build more sustainable agricultural systems. Since the 2018 Farm Bill, there has been renewed interest in hemp, however the high carbon footprint of modern production has led to questions about how to maintain or enhance product yields while minimizing negative environmental impacts. To develop sustainable hemp production practices, examining symbiotic associations and traits that were diminished during its domestication is a promising avenue to establish indicators and targets for future management and breeding efforts. The goals of this project are to inform and improve sustainable hemp production by examining the microbiome, plant, and soil impacts of hemp domestication, and to explore the potential for hemp “rewilding” to improve plant and soil quality while reducing fertilizer demand. We hypothesize that incorporating feral rootstocks and their associated microbiomes to domesticated hemp systems will enhance soil and plant quality, especially in nutrient deficient conditions. To test our hypothesis, we will i) assess how hemp domestication has influenced rhizosphere and endophytic microbiome composition and soil function, ii) evaluate how the introduction of feral rootstocks and microbiomes can moderate the microbial, soil, and plant response to N deficiency, and iii) identify key microbial taxa, functional guilds, functional processes, and root traits that are associated with ecologically and economically important plant and soil characteristics. Together, this project will identify empirically grounded hemp-specific soil and plant health targets to inform nitrogen-smart production practices and will improve mechanistic understanding of plant-soil-microbe interactions mediating sustainable hemp production.

Funding: United States Department of Agriculture

Predicting environmentally-important soil microbial functions across scales with novel soil sensing technology

Soil represents the second largest pool of carbon on Earth, and soil microbes like fungi and bacteria are key determinants of the amount of carbon sequestered in soil. Because relatively small changes in the amount of carbon sequestered can affect the amount of carbon dioxide in the atmosphere, soil microbes have the potential to mitigate or exacerbate climate change. Current biogeochemical models of carbon sequestration do not adequately incorporate soil microbial activity and this research team will use recently developed sensors to explore the role of soil microbes to carbon dynamics in diverse ecosystems. More specifically, this project will implement novel low-cost and efficient soil sensing platforms to facilitate the rapid estimation of microbial functions from thousands of samples collected across space and time in the continental US to improve predictions of future storage of soil carbon. Additional broader impacts of this project include experiential learning opportunities in soil ecology for high school students across Wisconsin as well as opportunities for young scholars in computer science to develop interactive games about soil sensing, microbial functions, and biogeochemical modeling.

Funding: National Science Foundation

Determining the microbial consequences of novel trait breeding in plants

Organic growers need vegetable varieties that are adapted to organic growing conditions and have market qualities demanded by organic consumers. In carrots, weed competition, nutrient acquisition, nematodes, and disease pressure are particularly critical challenges to both fresh market carrots and carrot seed production, while flavor, appearance, and nutrition are key market qualities. This project will deliver improved carrot varieties for organic producers and consumers; advance farmer participatory testing and breeding networks; improve understanding of how carrot genotypes interact with the root microbiome to access nutrients, prevent diseases, and alter the nutritional quality and storage potential of roots; and a breeding model that leverages
participatory field selection and marker assisted selection for organic cultivar development.

Funding: U.S. Department of Agriculture

Leveraging the soil microbiome to enhance the sustainability of bioproduct agroecosystems in low-fertility soils

Due to the increasing need to feed a growing human population, growing crops for bioproducts (like bioenergy, adhesives, resins, among others) on high-fertility agricultural lands has become a less viable practice. Consequently, developing innovative management practices to efficiently grow bioproduct crops on lands with poor quality soils is imperative. Crops like giant miscanthus (Miscanthus × giganteus), hybrid willow (Salix spp.), and switchgrass (Panicum virgatum) are a low-input bioproduct crops that are promising candidates for cultivation on poor quality soils. However, questions remain about how to best grow these crops on low-quality lands, how they will perform on different types of poor-quality soils, and whether poor-quality sites can produce abundant biomass of suitable quality while maintaining or improving ecosystem services. The aim of this research is to examine whether plant-soil-microbial feedbacks can be utilized to improve the nutrient use efficiency of bioproduct crops and their associated soil microbiome on poor quality soils across Appalachia and the mid-Atlantic region, USA. This project will illuminate microbial mechanisms to improve nutrient use efficiencies, plant growth, and ecosystem services while diminishing negative impacts of bioproduct crop cultivation on poor-quality soils.

Funding: U.S. Department of Agriculture

Uncovering microbial mechanisms mediating soil C storage in a changing world

Terrestrial ecosystems in the Northern Hemisphere are a globally important sink for anthropogenic CO2 in the Earth’s atmosphere, slowing its accumulation as well as the pace of climate warming. In northern temperate forests like those that cover almost 16 million acres in Wisconsin, historically high rates of anthropogenic nitrogen (N) deposition have enhanced the forest land carbon (C) sink by reducing soil organic matter (SOM) decomposition and increasing the amount of C stored in soils. Much of this increased C occurs as occluded particulate organic matter, which is a soil fraction that should be resistant to future microbial decomposition and stable over time. Although, anthropogenic N deposition has recently begun to decline across many temperate North American forests, and little is known about the fate of this forest land C sink during ecosystem recovery from historically high rates of N deposition. This research aims to identify how the microbial mechanisms that support the forest soil C sink in northern hardwood forests respond to a decline in historically high rates of anthropogenic N deposition. Data generated can be used to inform and improve ecosystem models to predict the fate of the terrestrial C sink in a changing world.

Funding: U.S. Department of Agriculture

Utilizing a trait-based approach to better understand microbial community dynamics in a model system

Microbial communities (microbiomes) play important roles in animals, plants, and even whole ecosystems. However, microbiomes are constantly changing through time and space. These changes can have big impacts on the health of animal or plant hosts and the functioning of entire ecosystems. For this reason, uncovering rules that govern how microbiomes change across time and space is essential for understanding how they affect their hosts and ecosystems. This research builds on previous understanding of different strategies used by microbes to survive and compete for resources and applies it to studying the ecosystem that forms in the pitchers of the carnivorous pitcher plant, Sarracenia purpurea. Through a combination of experiments and modeling, the S. purpurea microbiome will be studied to determine how microbial community functions change over time, how the host plant influences microbiome formation, and how the microbiome affects the host plant. The results will be compared with other aquatic, plant- and soil-associated microbiomes, to understand how S. purpurea pitchers can be relevant models for understanding roles of microbiomes in larger ecosystems.

Funding: U.S. National Science Foundation