When rhizobia bacteria colonize plant cells, they trigger the development of pink nodules on their roots that maintain the right conditions for the bacteria to convert nitrogen from the air into a form usable to the plant, essentially fertilizing the plant. A new genetic technique developed by researchers at Washington State University enabled the conversion of bacteria that lacked any of the genes needed to trigger the formation of root nodules or nitrogen fixation into new rhizobia strains that can do both. Credit: Stephanie Porter/WSU Most major crops, such as wheat and corn, require expensive nitrogen fertilizer to flourish. But what if bacteria could help those plants draw nitrogen from the atmosphere, as peas and beans do?…