Hello.
I'm going to start with a question:
Is anyone familiar with the blue algae problem? 
Okay, so most of you are.
I think we can all agree it's a serious issue.
Nobody wants to drink blue-algae contaminated water,
or swim in a blue-algae infested lake...right?
I hope you won't be disappointed, but today I won't be talking about blue algae.
Instead, I'll be talking about the main cause at the root of this issue,
which I have called "Phosphorus crisis".
Why have I chosen to talk to you about the phosphorus crisis today?
Well, because no one is talking about it. 
And by the end of my presentation I hope that citizens, the public, 
will be more aware of this crisis and this issue. 
Unfortunately, the truth is that this blue algae problem comes from
our agriculture. 
We use fertilizers in our agriculture-- synthetic fertilizers. 
What do we use synthetic fertilizers for? 
Basically, to help plants grow and to produce a better yield. 
The issue is that using fertilizers will create new types environmental problems.
Before going further, let me give you a crash course in plant biology. 
So, what does a plant need in order to grow? 
Sunlight, carbon dioxyde as well as the nutrients it will extract from soil. 
Among these nutrients, there are many essential chemical elements
such as phosphorus, nitrogen and calcium. 
The plant's roots will extract these elements.
Today I'll be focusing on a major problem linked to phosphorus.
Why phosphorus in particular? 
Because it is the most problematic chemical element.
By the end of my presentation, you will have seen the problems it poses,
as well as the situation we are in today. 
Phosphorus is a chemical element that is essential for life. 
This is important; and I'd like to stress its significance. 
Phosphorus is a major component in many of our molecules of life. 
Experts in the field will know that cellular communication is phosphorus-based:
phosphorylation and dephosphorylation.
Cell membranes are phosphorus-based: these are called phospholipids.
The energy in the bodies of all living things, ATP, is phosphorus-based.
And more importantly still, phosphorus is a major component of DNA --
something everyone is familiar with-- 
as shown in the image on this slide. 
DNA represents our genetical heritage. It is very important; and once again
phosphorus is an major part of it. 
Now, where do we get phosphorus from? 
As I explained earlier, plants extract phosphorus from soil, through water.
So we humans get it out of the things we eat: plants, herbs, fruits, vegetables,
but also out of eggs, meat and milk.
Naturally, some people eat healthier and are happier than others. 
This slide is a picture of modern or intensive agriculture. 
Intensive agriculture is based on synthetic fertilizers. 
Without them, we could not produce enough to feed the world's population
Speaking of humans, there are currently 7 billion of us on Earth. 
In less than 40 years, there will be 9 billion of us.
The question is simple: 
Do we have any phosphorus to feed future generations 50 years from now? 
I'm going to explain this problem, and where we're going to find phosphorus. 
Let's suppose we use an entire dose of phosphorus. 
Out of the 100% of phosphorus used, 15% goes to the plant
and 85% is lost. 
It goes through the soil, ends up in lake water; 
We then have lakes filled with phosphorus, hence the blue algae problem. 
As you can see here, there's something illogical in this process: 
100% of phosphorus is inputted, but only 15% goes to the plant. 
It seems like a waste; and it is!
What's worse is that it is very expensive. 
Nobody wants to throw their money out the window,
but unfortunately that's what is happening here. 
85% of one dose of phosphorus is lost. 
Modern agriculture depends on phosphorus supply:
There has to be a continuous supply: barely 15% is used by plants 
and the remainder is lost, so there is always a need for phosphorus. 
So where will we get this phosphorus from? 
Basically, phosphorus will be extracted from mines. 
This is the cover of an extraordinary article published by Nature in 2009
which first discussed the phosphorus crisis,
the growing scarcity of such an essential nutrient for life, 
and how not enough attention is given to the issue. 
Politicians and scientists alike agree that we are headed for a phosphorus crisis. 
What you are seeing here is an open-air mine in the United States. 
To give you an idea of the size of this mine, if you look in the top right-hand corner
you can see a crane, which is actually huge in real-life. 
So that gives you a sense of how big this mine is. 
Phosphorus is extracted in such mines. 
I compared the phosphorus crisis to that of oil.
The oil crisis, and its link to global warming, are talked about;
but the phosphorus crisis is not.
There are substitutes for oil:
we can replace it with biofuels, solar energy or hydro energy.
But phosphorus is an essential nutrient for life, and cannot be replaced. 
What is the current state of the world's phosphorus reserves? 
This graph shows you where we are today. 
The black curve represents predictions for phosphorus reserves. 
The curve reaches its apex in 2030 and stops off at the end of the century. 
The dotted curve represents the current evolution of phosphorus reserves. 
As you can see, both curves meet in 2030-- at which point I will have retired.
The graph illustrates that we are indeed headed for a major crisis 
and that is the idea I'd like everyone to be aware of.
So, are there solutions? What are we going to do? 
We are faced with a paradox.
There will be increasingly less phosphorus available;
by 2050 there will be 9 billion of us on Earth; 
and according to the Food and Agriculture Organization of the United Nations, 
we will need to produce twice as much food in 2050 than we do today. 
Less phosphorous on one hand, increased agricultural demand on the other. 
What do we do? 
This is truly a paradoxical situation. 
Do we have a solution, or a way of optimizing the way phosphorus is used? 
Remember what I said earlier: 85% of phosphorus is lost. 
The solution I'm offering today is one that has existed for a very long time,
even before plants existed on Earth.
It's a microscopic mushroom that is very mysterious, simple and yet also extremely complex. 
I've been fascinated by this little mushroom for over 16 years
and this fascination led me to further my research and to use the mushroom 
as a model for my laboratory research. 
This mushroom exists in symbiosis with its roots. 
By symbiosis, I mean a bidirectional and mutually beneficial association
which is also called a mycorrhiza. 
This slide illustrates the elements of a mycorrhiza. 
What you're seeing is a doubled root
Normally, a root will find phosphorus, 
but can only find it if it is located less than 1mm away from the root.
Past that distance, the root cannot detect phosphorus. 
Now with this microscopic mushroom
 that grows faster and is better able to find phosphorus, 
the root can extend past the 1mm zone to find phosphorus. 
I did not invent this
it's a biotechnology that has existed for 450 million years.
And over time, this mushroom has evolved and adapted 
in order to find even the smallest traces of phosphorus for the plant. 
What you're seeing on this slide is a carrot root
and the mushroom's very fine filaments.
When you look closely, you see how the mushroom penetrates the root
proliferate between the root's cells 
and eventually penetrate these cells to form an arbuscular structure,
which will considerably increase the exchange interface between the plant and the mushroom.
Thus, it is through this structure that mutual exchanges occur:
I give you phosphorus and you feed me. A true symbiosis. 
Now let's add a mycorrhiza plant into the schema I used earlier, 
but instead of using a 100% dose, I've reduced it to 25%.
Of this 25%, over 90% will be used by the plant. 
A very small amount of phosphorus will remain in the soil -- a natural occurrence. 
What's more is that in certain cases, we don't even need to add phosphorus. 
If you recall the graphs I showed you earlier,
85% of phosphorus is lost in the soil.
Yes, this remainder gets fixed to other elements in the ground;
but plants can no longer use it because it has become insoluble,
whereas a plant can only get nutrients in their soluble form. 
On the other hand, the mushroom can dissolve insoluble phosphorus
and it make available for the plant to use. 
To further support my argument, here is a picture that speaks for itself. 
What you are seeing are Sorghum fields.
On the right side, you see the yield produced using conventional agriculture
and with a 100% dose of phosphorus;
on the left side, the dose was reduced to 50%, and you can see a better yield. 
All this to show you that this a method that works.
 In some cases-- namely in Cuba, Mexico and India-- 
the dose can be reduced to 25%, or even neglected altogether 
because the mushrooms are well adapted to finding phosphorus in soils. 
This example is of soya production in Canada.
Mycorrhiza was used in one field, but not in the other.
In the former field, there is clearly a better yield -- as shown by the colour index, 
where blue shows a better yield, yellow a weaker yield,
and the black rectangle is the plot from which the mycorrhiza was added.
As I said before, I didn't invent this-- mycorrhiza has existed for 450 million years,
and is a phenomenon which has helped plant species diversify.
Moreover, it isn't something that is still under testing in a lab:
mycorrhiza exists, works, is produced at an industrial scale and commercialized globally.
The problem is that people are not aware of it
-- people like producers and farmers are still not aware of it. 
We have a technology that works, and that, if used and exploited correctly, 
will alleviate some of the pressure we are putting on world phosphorus reserves. 
To conclude, I am a scientist, and a dreamer
but above all I'm passionate about this topic.
So if you were to ask me what my retirement dream is, 
which corresponds to when we'll reach that phosphorus apex, 
it would be that we will be using one label, "Made with mycorrhiza"
and that my children, and grandchildren will be buying products with that label too. 
Thank you for your attention. 
