Rhizobia (image) American Society of Agronomy Share Print E-Mail Caption Rhizobia colonies from different regions growing in the lab. Soil is collected from various areas, and the microbes are isolated in solution. Credit Charlotte Thurston Usage Restrictions For use with story only. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.