It’s an exciting time to be a microbiologist working in rice research. A global push towards the cultivation of water-saving rice is enabling farmers to harness the power of microbes that thrive in less water.

Some farmers already use rice production systems that reduce or eliminate the length of time rice is submerged in a flooded paddy field. At the sowing stage, planting of pre-germinated seeds (direct seeding) rather than traditional transplanting of small plants into flooded paddies reduces the need for waterlogged fields. Waterlogged rice paddies emit huge amounts of methane, a potent greenhouse gas.

Similarly, an irrigation practice known as alternate wetting and drying uses pipes drilled into fields to encourage water management and intermittent flooding, reducing water usage and methane emissions.

Among microbes thriving in less water are arbuscular mycorrhizal fungi. These are beneficial soil fungi that live inside plant roots and help to extend plants’ reach into the soil to collect nutrients, acting as “natural biofertilisers”.

Arbuscular mycorrhizal fungi are aerobic, meaning they require oxygen for survival. This makes them more likely to be well suited to the drier, more aerated soils (with air spaces to allow efficient exchange of nutrients, water and air) that are increasingly promoted in sustainable rice systems.

To test this theory, I stepped out of the Crop Science lab at the University of Cambridge and into the field at the International Rice Research Institute (IRRI) in the Philippines.

Using some ink stain and a microscope, I examined roots from IRRI 154, a direct-seeded

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