The Wheat Field That Could Change the World | Guntur V. Subbarao | TED

What you see over there is

elite modern-day wheat lines

that have a special ability to produce

large amounts of antibiotics

from the root systems.

You may be wondering,

why do we need antibiotics from the wheat root systems?

You only take antibiotics when you are sick, isn't it?

The agricultural systems,

the modern farming systems have become

increasingly sick lately.

They are so sick that nearly 70 percent of the nitrogen fertilizers

that are being applied to farmlands

are being leaked out.

They're leaking nitrogen uncontrollably.

If you look at the nitrogen fertilizer consumption

from the beginning of the Green Revolution,

it has grown nearly 30 fold.

From five million metric tons

at the beginning of the Green Revolution,

to 150 million metric tons,

what we are currently using.

A 30-fold increase in nitrogen fertilizer consumption

has resulted in a four-fold increase in global food grain production.

Of course, we all know

that the Green Revolution has transformed the global food grain production,

saved us from famine,

food scarcities,

and provided the global food security.

But you have to ask yourself.

A 30-fold increase in nitrogen fertilizer consumption

is supporting only four-fold increase in food grain production.

What's happening?

When you apply nitrogen fertilizers,

it is mostly in ammonium form.

Ammonium form binds the soil, doesn't move.

Doesn't create any harmful nitrogen byproducts.

There's no problem with ammonium nitrogen.

But there is a little bacteria, lives in the soil,

that started eating away this fertilizer, nitrogen ammonium,

and spitting it out into nitrate.

And also it's making many other

harmful nitrogen byproducts.

The problem with the nitrates is,

though many plants can use nitrates as a nitrogen source,

but nitrogen cannot bind to the soil.

It washes out.

If you have rain, if you have irrigation,

it washes out from the farmlands.

That is the problem.

This little bacteria [that] used to be a small,

subdued microbial activity in the soil biological activity,

has grown now into a monster.

It's consuming nearly 95 to 99 percent of the fertilizer nitrogen

and splitting it out into nitrates.

We should be asking,

are we fertilizing our crops,

or are we fertilizing this little bacteria

which we have helped to grow into a big monster?

This is what happens when the nitrogen moves into water streams,

pollutes lakes,

triggers algal blooms

and creates another Green Revolution.

If you don't keep the nitrogen in farmlands,

if you allow it to move into the water bodies,

to the larger ecosystem,

it creates another Green Revolution in a ecologically destructive way.

If you look at the soil,

it's a living biological system.

An invisible microbial world.

There's a large microbial universe operating in these soil systems.

They are involved in numerous functions,

breaking down everything into individual components,

nourishing our crops to grow and produce food.

It's so complex.

It's much, much bigger than the ecosystem that we know,

the ecosystem above the ground that we know.

It's much more complex.

Just to give you an example,

a gram of soil would have about 10 billion microbial cells.

Ten billion microbes in a gram of soil, doing various functions.

It's much larger than the entire human population,

what you see on Earth.

This microbial universe is affected,

affected so severely,

from the last seven decades of the Green Revolution.

Particularly,

the infusion of large amounts of nitrogen fertilizers

caused disruption to this microbial activity

and changed the population dynamics.

As I said, what used to be a small,

insignificant microbial activity in the soil

has grown into a monstrous proportion,

sucking up all the fertilizer nitrogen [that] we are applying.

Nature has evolved many solutions

to some of the problems we are facing in agriculture

and some of the problems we are going to create

and face in the future.

What you see over there is a Brachiaria tropical pasture grass.

It grows extensively in South America.

It has a unique ability.

It produces large amounts of antibiotics from the root systems.

These antibiotics are specifically directed to this little bacteria,

we say the nitrifying bacteria.

Because of that, it tightly controls

this nitrifying bacteria function in the soil.

It doesn't allow it to function.

It doesn't kill that bacteria,

but it doesn’t allow it to function,

just [keeps] them in a kind of coma state.

Because of that,

you don't see any kind of nitrate formation

in these tropical pastures.

In particular, this tropical pasture grass.

And also, you don’t see any nitrogen gas emitted from these pastures.

No nitrous oxide is emitted from these pastures

because it controls these bacteria so tightly

by producing large amounts of antibiotics from the root systems.

The question is,

how do we bring this kind of ability into our crop lands?

Most of our food production comes from four crops:

Wheat, maize, rice and sorghum.

These are the four crop that provide the global food security.

Almost 80 to 90 percent of the food grains are produced from these four crops.

And also ... more than 90 percent

of the entire nitrogen fertilizer produced industrially

goes to these four production systems.

These food crops, the staple crops,

don't have much ability.

That's the reason they are leaking.

So, if you look at this, you see the wild wheat.

It has the ability to produce 20 to 30 times antibiotics

from the root systems.

Our group has worked for the last 15 years

to try and locate the genomic region

responsible for producing these antibiotics

and transfer to the cultivated wheat.

We have done it.

You see that the orange,

orange is here part of the chromosome that is coming from the wild wheat,

which is coding the antibiotics.

We have got that integrated to the wheat genome

without disrupting the elite [agronomic] architecture of the wheat system,

and also without disrupting the yield potential

and without interfering with the bread-making quality of the wheat.

This new category of wheats we call BNI-wheats,

the wheats that can produce large amounts of antibiotics

from the root systems

to control this bacteria

so that they can control the nitrate production in the root systems.

Because of this,

the nitrogen fertilizer, whatever we are applying,

would stay in the [root-zone], doesn’t leak.

Look at the the BNI wheats, well, it looks quite healthy and green.

You see the right side,

that is the current modern wheats,

which leaks out all the nitrogen, whatever we have applied.

Both the plants were applied the same amount of nitrogen

at exactly the same time.

In one case, it leaked out.

In the other case, it remained in the farmland.

These are the BNI wheats.

These are the next generation wheats under development.

So in a few years from now,

they will be available to the farmers.

So our hope is, in the next 10 years,

most of the wheats that are grown in different parts of the world

would have this kind of ability

so that the nitrogen leakage can be stopped

by infusing these large amounts of antibiotics

from the root systems.

That’s what is going to control --

that’s what is going to reduce the amount of nitrogen fertilizer in future ...

in wheat root systems.

Thank you.

(Applause)