Using Bacteria for Crop Fertilization


A major challenge for organic farmers lies in determining the right amount of nitrogen (N) to add to crops and the best time to do it. Farmers using organic nitrogen fertilizers such as manure and compost face serious limitations because these fertilizers, which often come from off the farm, are low in N content, often hauled long distances, and can contribute to soil salinization.

Researchers at Colorado State University are working on an alternative that addresses many of these limitations, testing the production and use of cyanobacteria based fertilizer (cyano-fertilizer) on a university research farm and two private orchards. Cyano-fertilizer takes advantage of the ability of cyanobacteria to perform nitrogen fixation, taking N from the atmosphere and making it available to plants. On-farm cyano-fertilizer production is an entirely new and innovative approach to providing crop N requirements using high-N bacterial biomass, while greatly reducing fertilizer manufacturing and transportation needs.

Preliminary data from greenhouse studies has shown that cyano-fertilizer increased plant flowering and crop beta-carotene concentrations. The purpose of this project is to broaden this work to include fish emulsion (hydrolyzed and non-hydrolyzed) and kelp to evaluate their phytohormone concentrations and impact on the nutritive value of organic crops.

OFRF provided funding for the project, which is being led by Jessica Davis, a Professor in the Department of Soil and Crop Sciences at Colorado State. The research continues with a grant from the USDA Western Sustainable Agriculture Research Program. Researchers at the University of Wyoming became interested in the work being done at Colorado Sate and have received a Wyoming Specialty Crops grant to further evaluate cyano-fertilizer production and utilization on a diversified vegetable farm.

Davis and her team have written a manual titled, “Building a Raceway for Cyanobacterial Bio-fertilizer Production.”

A variety of outreach and education tools are also being developed to share the research findings and techniques with farmers.

View the final report here.