Giles E.D. Oldroyd

So I believe this soybean plant is a prototype for sustainable food production on this planet.

So on the roots of this soybean plant are nodules.

And these nodules do an amazing thing.

They harbor millions of bacteria inside the cells of the nodules.

And those bacteria are able to capture nitrogen out of the atmosphere and confede it to this soybean plant.

Now, all plants require a source of nitrogen.

They need it so they can make DNA, RNA and proteins.

But plants can't access the most prevalent form of nitrogen on the planet, the 78 percent of the air that you're currently breathing, that is molecular dinitrogen.

only bacteria that possess the enzyme nitrogenase can convert this very inert form of nitrogen and convert it into ammonia, a reactive form of nitrogen that bacteria and plants can use to make their DNA, RNA and proteins.

So the bacteria inside the nodules of this soybean plant are fixing nitrogen out of the air, converting it into ammonia, and then feeding that ammonia to this soybean plant.

In return, the soybean plant is feeding the bacteria with a source of carbon in the form of sugars derived from photosynthesis in the leaves.

This is what we call a mutualistic symbiosis.

It's beneficial to the soybean plant, but it's also beneficial to the bacteria inside those nodules.

Now, the roots of the soybean plant are doing a second amazing thing, and to see that, we have to look under a microscope.

The roots are heavily infested with a beneficial fungus called mycorrhizal fungi, and these fungi are heavily colonizing the soil and make a much greater contact with the soil surface than the plant root alone is able to achieve.

In so doing, they create a much more efficient platform for the uptake of nutrients, nutrients such as phosphates, nitrates, potassium and water.

The fungus isn't only out there in the soil, it's also colonizing the roots of this soybean plant, where it makes these highly branched fungal intrusions into the cells of the root that we call our buscules.

So the fungus is out there in the soil, capturing nutrients from the soil, and it feeds those nutrients to the soybean plant through these arbuscular intrusions.

In return, the soybean is feeding the fungus with carbon from photosynthesis.

Again, it's a mutualistic symbiosis.