Validating Nitrogen Fixing Ability of Previously Identified Microorganisms in Manure

RESEARCHER: Elizabeth Maga, UC Davis

TIMELINE: January 2020 to December 2021

BACKGROUND: California dairy farms use manure as a fertilizer, reducing the need for chemical fertilizers; correct management is important. Identification of specific microbes involved in the nitrogen cycle in dairy manure could lead to strategies to mitigate environmental impacts and improve the fertilization potential of manure. Previous work surveying the microbial populations present in the manure of lactating cows on commercial dairy farms in California using DNA sequencing and bioinformatics analysis identified bacteria capable of fixing nitrogen present in the manure. These microbes may play a role in controlling the concentration and form of nitrogen in the manure of commercial dairy cattle.

OBJECTIVE: To validate predictions from a previous CDRF-funded study that identified potential microbial populations that can fix atmospheric nitrogen into more usable forms. To determine if these strains are able to fix nitrogen and potentially enable the future development of strategies such as dietary manipulation or post excretion treatment technology to modify microbial populations within facilities or throughout the storage/treatment/utilization environment to either enhance or reduce bacteria related to the nitrogen cycle.

INDUSTRY BENEFIT: Knowledge of the nitrogen fixing capacity of microbes in manure can lead to the development of strategies such as dietary manipulation or post excretion treatment technology to modify microbial populations within facilities or throughout the storage/treatment/utilization environment to either enhance or reduce bacteria related to the nitrogen cycle. This will allow dairy producers to better manage manure for reducing environmental impacts and improving crop growth.