FARMERS will no longer need to buy fertiliser for their crops, if American research pans out – plants will simply create their own.
Scientists at Washington University in St Louis scientists say their discovery could have a revolutionary effect on agriculture and the health of the planet.
Creating fertiliser is energy intensive and the process produces greenhouse gases that are a major driver of climate change. It’s also inefficient with less than 40 per cent of the nitrogen in commercial fertiliser making it to the plant.
Fertiliser washed away by rain winds up in streams, rivers, bays and lakes, feeding algae that can grow out of control, blocking sunlight and killing plant and animal life below.
There is another abundant source of nitrogen – the Earth’s atmosphere is about 78 per cent nitrogen, and senior research associate Maitrayee Bhattacharyya-Pakrasi and his team has engineered a bacterium that can make use of that atmospheric gas in a significant step toward engineering plants that can do the same.
The bacteria, Cyanothece, is able to fix nitrogen because of something it has in common with people.
“Cyanobacteria are the only bacteria that have a circadian rhythm,” project leader Prof. Himadri Pakrasi says. “Cyanothece photosynthesise during the day, converting sunlight to the chemical energy they use as fuel, and fix nitrogen at night, after removing most of the oxygen created during photosynthesis through respiration.”
The next step for the team is to dig deeper into the details of the process and collaborate with other plant scientists to develop nitrogen-fixing plants.
Crops that can make use of nitrogen from the air will be most effective for subsistence farmers – raising yields on a scale beneficial to a family or a town and freeing up time that now is spent manually spreading fertiliser.
“If it’s a success, it will be a significant change in agriculture,” Bhattacharyya-Pakrasi says.