Microbes could help reduce the need for chemical fertilizers

New coating protects nitrogen-fixing bacteria from heat and humidity, which could allow them to be deployed for large-scale agricultural use. Production of chemical fertilizers accounts for about 1.5 percent of the world's greenhouse gas emissions. MIT chemists hope to help reduce that carbon footprint by replacing some chemical fertilizer with a more sustainable source - bacteria. Bacteria that can convert nitrogen gas to ammonia could not only provide nutrients that plants need, but also help regenerate soil and protect plants from pests. However, these bacteria are sensitive to heat and humidity, so it's difficult to scale up their manufacture and ship them to farms. To overcome that obstacle, MIT chemical engineers have devised a metal-organic coating that protects bacterial cells from damage without impeding their growth or function. In a new study, they found that these coated bacteria improved the germination rate of a variety of seeds, including vegetables such as corn and bok choy.