Bioinoculant products in agriculture represent one of the fastest-growing markets in the world, with an approximate 17% annual increase and an anticipated market value of $12 billion US by 2026

The University of Maryland Eastern Shore (UMES) received a $206,482.20 Project Grant from the U.S. Department of Agriculture's National Institute of Food and Agriculture (NIFA) under the Agriculture and Food Research Initiative (AFRI) program (CFDA 10.310), awarded July 15, 2025, with completion targeted for July 14, 2027. The project addresses the variable efficacy of microbial inoculants in agriculture by conducting controlled research to enhance the establishment and performance of biological soil amendments. Specifically, the research manipulates propagule pressure variables—including inoculation frequency and cell concentration—using two organismal types: arbuscular mycorrhizal fungi (Rhizophagus irregularis) and bacteria (Bacillus licheniformis). The study will assess impacts on plant performance, soil microbiota composition, and soil health parameters through a two-year greenhouse-based experimental approach utilizing high-throughput genomic sequencing tools.

The project aims to advance understanding of how microbial amendments affect soil health and microbiome dynamics, ultimately improving the adoption and efficacy of bioinoculant products within the broader agricultural industry. A subaward of $66,692.00 was issued to Katherine Tully at the University of Maryland, College Park (awarded September 12, 2025) to support collaborative research contributions under the UMES grant. This research directly supports AFRI's priority area of Bioenergy, Natural Resources, and Environment by generating data to optimize biological tools for more sustainable and resilient agricultural systems.

New regulatory constraints placed on the agrochemical industry are expected to reduce consumer demand for chemical inputs and position the microbial-based inoculants industry to absorb part of this current $250 billion market. The adoption of biological tools offers a promising pathway toward more resilient, efficient, and ecologically responsible agricultural systems, ultimately shaping the future of sustainable food production. However, the variable efficacy of microbial inoculants and our limited understanding of their effects on soil health and the microbiome have severely hampered the widespread adoption of microbial-based products. This proposed research will directly contribute to improving microbial inoculant success and advance our understanding of the interannual effects of biological amendments in soil. Aims 1 and 2 will leverage ecological theory to experimentally manipulate the components of propagule pressure (e.g., number of inoculations and number of cells per inoculation) to enhance inoculant establishment, improve plant performance, and understand the implications of microbial inoculations on soil health. This study focuses on two distinct organismal types (i.e., arbuscular mycorrhizal fungi - rhizophagus irregularis, and bacteria - bacillus licheniformis) associated with microbial-mediated phosphorus acquisition in plants. Our experimental approach will assess the effects of microbial amendments on plant performance, the soil microbiome, and a suite of soil health parameters. We will grow plants in a climate-controlled greenhouse over two consecutive years. At the end of each growing season, we will use high-throughput genomic tools (e.g., 16S and its amplicon sequencing) to describe the soil microbiome following the application of biological amendments at different rates. Additionally, we will employ a suite of biogeochemical measurements to understand the implications of microbial amendments on soil health and the associated temporal patterns over two growing seasons. In particular, the data generated from this experiment will directly contribute to improving microbial inoculation methods and increasing microbiome-mediated phosphorus acquisition in plants. Together, this work will lead to a decreased dependence on synthetic agrochemicals and promote sustainable agricultural practices.