New Ways to Future Proof Viticulture – In Conversation with Antonio Graça

What do we need to future proof the vineyards of tomorrow? What breeding techniques and technologies will viticulturists need in order to stay resilient in the face of climate change and its attendant problems, including disease pressure? To help unravel the issues, ARENI spoke with António Graça, Head of Research and Development at Sogrape in Portugal, and Secretary for Sustainable Development and Climate Change Group at the OIV.

ARENI

Why can’t we sow vine seeds, and why do we have to go through clonal or massale selection?

António Graça

The grape vine can reproduce in two different ways. It can reproduce sexually or asexually. So when we get a seed and put it in the ground, that would be sexual reproduction. Meaning that the offspring would not be either parents. We people come out of sexual reproduction. So each child is a combination of each one of the parents. The same happens when you take a seed from a grapevine, because that means the plant was cross-fertilised by pollination and therefore it’s actually the result of the genetic material of two different parents. 

Now the problem is that when you plant a vineyard, you want to have some type of reliability as to the result. You avoid sexual reproduction and instead use asexual reproduction. You cut a piece of the cane of a parent plant.

ARENI

If we control so tightly, how come it’s still able to mutate and change?

António Graça

Because life is powerful. When you replicate a plant, you are actually replicating millions of cells and when you have a cell dividing , there is the possibility of having some minor mistakes in the copy. Now those mistakes will account for very small differences in the behaviour of the offspring plants. Over different generations, they will create the necessary diversity for adaptation of the best plants. 

So now you could ask what is the point of having asexual reproduction if we still have evolution? Well, because the rates of these changes through sexual reproduction is millions of time higher. At the end of the day, it’s all about adaptation and survival.

ARENI

Grape varieties do not behave the same way when it comes to adaptation and mutation, right?

António Graça

Pinot Noir has been around for a very long time and so it had time enough to diversify its genetic makeup. The number of differences in the individuals of a single variety is a measure of how long that variety has been around. If you take a variety like Alicante Bouschet that was produced by crossing at the end of the 19th century, the actual genetic diversity is orders of magnitude lesser than a variety like Pinot Noir. This is a very good measure of how old the variety is and how often it has been replicated during time. The more times there are replicates, the higher the probability of small mistakes accumulating over time. If you take a good representative sample of any variety and you measure the level of diversity within the variety, that is a very good relative measure of how long the variety has been around.

ARENI

Looking at massal and clonal selection: do both way of selecting plant material offer the same opportunities for the future of fine wine? How do you chose between the two approaches when managing the large surface you are responsible of?

There is actually a third type of selection which is polyclonal selection. But let’s start with massal and clonal selections. Massal selection is when you go to different vineyards, you round up a number of different plants and you mix them all together and you plant them. Its main characteristic is that you have a high level of genetic diversity. When you go for clonal selection, you single out a single plant and then you replicate that plant asexually to ensure the maximum possible genetic stability. It’s never a hundred percent. Even when you replicate by cane, there are small mistakes that get into the replication of the plant and with time these mistakes will accumulate.

With clonal you are trying to keep the original makeup as stable as possible along time. The problem is that, unlike with massal selection, you have no genetic diversity. When you are in a changing environment, you do not have the necessary genetic diversity to keep adapting to the changes. So clonal selection in the grapevine came about during the late 19th century, but it was mainly deployed massively after the Second World War. And the idea is to be able to keep the characteristics of the best genotypes of each variety and keep the behaviour of the variety as stable as possible.

That was okay until the climate started to change. When the climate started to change, these plants started to show that they were not behaving in a way that would counter those changes in climate.

The number of differences in the individuals of a single variety is a measure of how long that variety has been around.

António Graça, Head of Research and Development at Sogrape

ARENI

But the interest in clonal was also because all the individuals behave in the same way. Then you’ve got greater consistency and ripeness for example, or maybe an easier way to manage your parcel. 

António Graça

The main issue with clonal selection was to ensure sanitary quality, to make sure that the plant was not affected by a number of serious viruses. As long as the environments and the conditions where the plants were cultivated were stable, and the final outcomes in terms of products and market were also stable, this worked. And this was the drive towards efficiency. But as always happens that when you increase your drive towards efficiency, you lose resilience.

When you increase your drive towards efficiency, you lose resilience.

António Graça, Head of Research and Development at Sogrape

ARENI

What’s your policy when it comes to selecting plant material?

António Graça

Well of course the first thing for plant material is sanitary quality. It always has been, it still is. We need good stable economic outcome. But more and more we are increasing the genetic diversity of our vineyards, more and more through polyclonal selection. Instead of having a single clone, we use a selection of between seven to 20 clones. 

We have to have in the beginning a representative sample of the natural diversity of the variety. Genetic diversification requires time. So once we have this good representative sample, we characterise them according to the traits of interest. It can be productivity, it can be sugar content in the berries or anything that you can measure in the plants. 

You characterise the whole sets of genotypes and then you select a small number of those that maximise the traits that you want to select. You are achieving genetic gain because you are selecting those that behave better, but at the same time you are achieving stability. It is not just one but several genotypes that together maximise the gain you are looking for. The final result will be something that remains pretty much stable.

“We are increasing the genetic diversity of our vineyards, more and more through polyclonal selection. Instead of having a single clone, we use a selection of between seven to 20 clones.”

António Graça, Head of Research and Development at Sogrape

ARENI

Is that something that some of the New World countries might not have access to, because they have more restricted access to vine material?

António Graça

It depends. In Europe, the only country that can do polyclonal selection is Portugal. And that’s because Portugal has been researching and generating data on its varieties in this way; good representative samples that have been put into trials with an adequate experimental design, to extract the true genetic value of each genotype. Only Portugal has done that so far and it took more than 40 years to do it. Today we have the capacity to do that. Other countries are starting now. For example, you take France or even Germany, they do have in conservation a quite high number of genotypes of their major varieties. The problem is that they have not yet made the trials under an adequate experimental design. Portugal has done that for the last 40 years, for more than 70 varieties already.

ARENI

And how long have been using that technique for planting the vineyard at Sogrape? How long have you used this?

António Graça

We are actually starting to use it now. We have a lot of trials that were done in the last 20 to 25 years to fine tune the methodology. We do have polyclonal vineyards, but experimental polyclonal vineyards rather than vineyards that were planted with the specific goal of making a stable commercial production. That is what we are doing now.

The OIV has  approved and published the resolution on polyclonal selection only in 2019. We started the proposal in 2014 and it took five years because that’s how the process goes. But we have that now, and in December last year, Portugal created the first certification for polyclonal material of grape vines in the world. This is the right time, because we are being faced by such high pressure from the environment and markets that we really require this capacity.

ARENI

And I’ve also read a lot about the new breeding technologies. So including for example, gene editing and its potential to enhance the plant’s resistance to fungal disease, for example.

António Graça

There are two perspectives to this and it has got to do with what the type of production and offer in the markets is that you want to propose. Gene editing can be―and will be, in my opinion― an interesting technique if you want to ensure the production of very high quantities of wine of the same type. It still has a problem, which is it has no diversity. Now the problem is that a plant is not a machine and when you reduce the genetic diversity towards a single trait that you want to keep as stable as possible, if the environment changes, that plant will be a lot more susceptible to change.

You could argue: but we can produce by gene editing a lot of different plants. That is true. But then you need time to understand how they work and which are the ones that work best. So you’ll be taking a lot more time to do what nature has already been doing for you.

ARENI

But theoretically, you could gene edit against mildew for example. 

António Graça

That’s true of course. However, you are just focusing on a specific trait and plants, like any organism, have to face multiple pressures. Therefore if you are reducing the genetic diversity of your vineyard as a whole, you are making your vineyard more susceptible to changing threats.

Today, in the vast majority of vineyards across the world,  vineyards are planted with one single genotype. So we have a huge lack of genetic diversity that makes vineyards across the world very susceptible to changing environments.

Today, in the vast majority of vineyards across the world,  vineyards are planted with one single genotype. So we have a huge lack of genetic diversity that makes vineyards across the world very susceptible to changing environments.

António Graça, Head of Research and Development at Sogrape

ARENI

And that leads us to hybrids.

António Graça

Hybrids are plants that have been obtained by a purposefully designed program of breeding. Crossing plants to a point that you will get a gene or a number of genes that are coming from the non vinifera varieties and that provide resistance to specific pathogens, [like] downy mildew. And then you cross that first hybrid again several times with vinifera plants to decrease the non-vinifera DNA up to a point that only a small amount, including the resistant gene, will be left in the plant. 

ARENI

Who owns it? What are the proprietary rights on a hybrid?

António Graça

According to intellectual property law in Europe and in many other countries, the entity who created it is the owner of the rights. It’s a whole lot different to what happens with the natural varieties, because natural varieties are a heritage of the earth.

They don’t own the varietal. They may own the selection that was made. People who make a selection are entitled to have royalties of that selection. But it’s just the selection, not the variety. Natural plants or natural animals are no one’s property. They belong to all of us.

ARENI

We spend quite a lot of time trying to define what fine wine is. Is there a world in the near future where we would be able to separate fine wine because it comes from a vineyard that is 100% [vitis vinifera]?  Is there a scenario where we’ll be using the vegetal material to separate the quality of the wines? 

António Graça

I cannot tell you if it will happen. It depends on how the market will react to it I think. However, if genetic manipulation becomes something more usable in the wine sector, I’m pretty convinced that there will be a bi-polarization of the market. There will be wines that are produced with artificial varieties or cultivars. 

The way I see it is that nature has been doing a great job of selecting those varieties along thousands if not millions of years. So what is the point of throwing all that heritage right out the window and then start doing it yourself?  It took thousands or millions of years for nature to do it and it’ll take humanity pretty much the same time.

ARENI

Is the need for more diversity and more resilience the same thing for rootstock? Can we work with polyselection for rootstock as well, and have a vineyard planted with 10 different ones?

António Graça

Yes, there is a case for selection of rootstocks as well. One of the effects of climate change is that it is moving the areas where we make viticulture northwards, where potentially you are already having some challenges, not just in terms of soil but also in terms of climate. 

I think that one of the most interesting and important developments in viticultural science these days is that it is the start of understanding how soil biodiversity works.

It was not ignored. We knew there was something there, but now we have the tools to dig in. How does this universe of species from bacteria to fungus to insects and worms and so on, how are they interacting with each other? Because one thing that we should not forget is that one of the major effects of climate change is the change of temperature in the soil. It is quite striking the change in the soil temperatures across the last 20 to 25 years. And by changing the temperature all these balances are changing as we speak.

One thing that we should not forget is that one of the major effects of climate change is the change of temperature in the soil.

António Graça, Head of Research and Development at Sogrape

ARENI

How does that [need for more resilience] translate at a day-to-day, practical level? What does it mean for people that work in the vineyards?

António Graça

Two things. First of all, we are working at the level of the individual plant with remote detection technology. We can now understand which plant is in which state. And it doesn’t mean we manage them one by one, but it means that we can draw the borders between where the different phenomena are occurring with precision. The second thing is that we moved from process-based management to systems-based management. We do not think linearly anymore. We consider what is our vineyard as a web of multiple interactions. This is a huge change in mindset because before, vineyards were pretty much managed as if they were factory processes. And today we are finally coming to terms with managing them as complex entities of living beings.

We do not think linearly anymore. We consider what is our vineyard as a web of multiple interactions. This is a huge change in mindset because before, vineyards were pretty much managed as if they were factory processes. And today we are finally coming to terms with managing them as complex entities of living beings.

António Graça, Head of Research and Development at Sogrape

ARENI

Does it mean that workers have to be trained differently because they receive information on their smartphone? Say, I’ve got my smartphone and I scan the QR code of the vine and then I actually see what needs to be done for that one?

António Graça

In an ideal world, that would be how you should do it. Of course we do not live in an ideal world and more than that we are living in a world in transition. So we have to move from a process-based approach to vineyard management that it’s still very much what is being done in many places today to a systems-based approach to vineyard management. It requires time and requires qualifications. One of the best examples of how a vineyard is managed in a systems-based thinking is pruning. Any good worker who knows how to prune knows that you do not prune every plant in the same way. You look at the plant, you interpret the plant, you decide what you want to have, and then you cut what you have in order to achieve that. This is systems-based thinking.

So why would we, for example, spray a protection product the same way across a whole hectare of plants? Today we are evolving towards variable rate application technology, which is applying just the enough amounts of product that the plant requires. I believe that in 10 to 15 years, pretty much all viticultural operations will be done in this way. 

We need to qualify more and more of our vineyard workers in order for them to be able to interpret how best to apply their actions to what they see in the field. At the same time, we are developing more tools to help them do that.

ARENI

I came across this word a couple of times in the last six months and I had never heard of it before: ‘meta ethical’ viticulture. It’s the deep question about our core assumptions and the foundation of our moral system. It’s about asking or questioning the assumption of what is good in terms of viticultural practice. Is that something that comes to your radar? 

António Graça

I have followed the work of Giovanni Cargnello. The idea of meta ethical is to have a set of ethics that is applied universally and to understand how that set can be managed to the benefit not just of the growers or the wine makers, but for everyone who is involved in the value chain. It’s a wide reaching concept and I think it’s quite interesting when we have started living in a globalised world where we have many different views, approaches, and even philosophies of production coming together and competing in the same markets. The whole idea of meta ethical viticulture can be really interesting if applied to concepts like sustainable production systems.


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