How we can make crops survive without water | Jill Farrant

Prevodilac: Nikolina Ajdukovic Lektor: Mile Živković

I believe that the secret to producing extremely drought-tolerant crops,

Verujem da je tajna stvaranja useva ekstremno otpornih na sušu,

which should go some way to providing food security in the world,

koji bi na neki način obezbedili hranu u svetu,

lies in resurrection plants,

u oživljavanju biljaka,

pictured here, in an extremely droughted state.

ovde na slici, u ekstremnom stanju suše.

You might think that these plants look dead,

Možda mislite da ove biljke izgledaju mrtve,

but they're not.

ali nisu.

Give them water,

Dajte im vodu,

and they will resurrect, green up, start growing, in 12 to 48 hours.

i one će oživeti, pozeleneti, počeće da rastu za 12 do 48 sati.

Now, why would I suggest

Zašto bih ja sad predložila

that producing drought-tolerant crops will go towards providing food security?

da proizvodnjom useva otpornih na sušu možemo napredovati u sigurnosti hrane?

Well, the current world population is around 7 billion.

Pa, trenutni broj ljudi na svetu je oko 7 milijardi.

And it's estimated that by 2050,

I procenjuje se da će do 2050.

we'll be between 9 and 10 billion people,

biti između 9 i 10 milijardi ljudi,

with the bulk of this growth happening in Africa.

i većina rasta će se dogoditi u Africi.

The food and agricultural organizations of the world

Poljoprivredne i prehrambene organizacije sveta

have suggested that we need a 70 percent increase

navode da nam je potrebno povećanje za 70%

in current agricultural practice

u trenutnoj praksi poljoprivrede

to meet that demand.

kako bi se ispunila ta potražnja.

Given that plants are at the base of the food chain,

Gledajući na to da su biljke osnova lanca ishrane,

most of that's going to have to come from plants.

većina toga moraće da dođe od biljaka.

That percentage of 70 percent

Tih 70%

does not take into consideration the potential effects of climate change.

ne uzima u razmatranje potencijalne efekte klimatskih promena.

This is taken from a study by Dai published in 2011,

Ovo je preuzeto iz Dajevog istraživanja, objavljenog 2011,

where he took into consideration

gde je uzeo u razmatranje

all the potential effects of climate change

sve potencijalne efekte klimatskih promena

and expressed them -- amongst other things --

i između ostalog istakao je

increased aridity due to lack of rain or infrequent rain.

povećanu sušu zbog slabe kiše i retke kiše.

The areas in red shown here,

Delovi označeni crvenom bojom

are areas that until recently

delovi su koji do nedavno

have been very successfully used for agriculture,

bili uspešno korišćeni za poljoprivredu,

but cannot anymore because of lack of rainfall.

ali ne mogu više da se koriste zbog slabe kiše.

This is the situation that's predicted to happen in 2050.

Ovo je situacija koja je predviđena u 2050.

Much of Africa, in fact, much of the world,

Većina Afirike će biti, kao i većina sveta

is going to be in trouble.

u velikoj nevolji.

We're going to have to think of some very smart ways of producing food.

Moraćemo da smislimo pametne načine za proizvodnju hrane.

And preferably among them, some drought-tolerant crops.

A među njima bi bilo dobro da imamo i neke useve otporne na sušu.

The other thing to remember about Africa is

Druga stvar koju moramo zapamtiti za Afriku

that most of their agriculture is rainfed.

je da se većina njihove poljoprivrede snabdeva kišom.

Now, making drought-tolerant crops is not the easiest thing in the world.

Stvaranje useva otpornih na sušu nije najlakša stvar na svetu.

And the reason for this is water.

Razlog je voda.

Water is essential to life on this planet.

Voda je glavna stvar za život na ovoj planeti.

All living, actively metabolizing organisms,

Svi živi organizmi sa aktivnim metabolizmom

from microbes to you and I,

od mikroba do mene i vas,

are comprised predominately of water.

sastoje se najviše od vode.

All life reactions happen in water.

Sve životne reakcije se događaju u vodi.

And loss of a small amount of water results in death.

gubitkom male količine vode, rezultiraju smrću.

You and I are 65 percent water --

Ja i vi smo 65% sačinjeni od vode,

we lose one percent of that, we die.

ukoliko izgubimo 1% toga, umiremo.

But we can make behavioral changes to avoid that.

Ali možemo učiniti promene ponašanja kako bi izbegli to.

Plants can't.

To biljke ne mogu.

They're stuck in the ground.

One ostaju u zemlji.

And so in the first instance they have a little bit more water than us,

Kao prvi primer, oni imaju više vode od nas,

about 95 percent water,

oko 95% vode,

and they can lose a little bit more than us,

i mogu da izgube malo više od nas,

like 10 to about 70 percent, depending on the species,

od 10 do 70 procenata, u zavisnosti od vrsta,

ali samo u kratkim vremenskim periodima.

but for short periods only.

Most of them will either try to resist or avoid water loss.

Večina njih će probati da pruža otpor ili da izbegava gubitak vode.

So extreme examples of resistors can be found in succulents.

Ekstremni primeri onih koji pružaju otpor mogu se naći u sukulentima.

They tend to be small, very attractive,

Inače su male, veoma atraktivne,

but they hold onto their water at such great cost

ali se drže njihove vode po svaku cenu,

that they grow extremely slowly.

da rastu jako sporo.

Examples of avoidance of water loss are found in trees and shrubs.

Primeri onih koji izbegavaju gubitak vode mogu se pronaći u drveću i žbunju.

They send down very deep roots,

Oni šire veoma duboke korene,

mine subterranean water supplies

prave podzemne zalihe vode

and just keep flushing it through them at all times,

koja se rasipa po njima stalno,

keeping themselves hydrated.

i tako ostaju hidrirani.

The one on the right is called a baobab.

Na desnoj strani je drvo koje se naziva baobab,

It's also called the upside-down tree,

takođe se naziva i naopako drvo,

simply because the proportion of roots to shoots is so great

zato što je deo od korenja do izdanaka toliko veliki

that it looks like the tree has been planted upside down.

da daje izlged kao da je drvo naopako posađeno.

And of course the roots are required for hydration of that plant.

Naravno, koreni su potrebni za hidrataciju te biljke.

And probably the most common strategy of avoidance is found in annuals.

I verovatno najčešća strategija izbegavanja

je kod jednogodišnjih biljki.

Annuals make up the bulk of our plant food supplies.

Jednogodišnje biljke čine većinu naših zaliha biljaka.

Up the west coast of my country,

Na zapadnoj strani moje zemlje,

for much of the year you don't see much vegetation growth.

većinom godine ne možete videti mnogo rasta vegetacije.

But come the spring rains, you get this:

Ukoliko dođete za vreme prolećnih kiša, dobićete ovo-

flowering of the desert.

cvetanje pustinje.

The strategy in annuals,

Strategija kod jednogodišnjih biljki,

is to grow only in the rainy season.

je da rastu samo kada je sezona kiše.

At the end of that season they produce a seed,

Na kraju te sezone, one naprave seme,

which is dry, eight to 10 percent water,

koje je suvo, 8 do 10 procenata voda,

but very much alive.

ali veoma živo.

And anything that is that dry and still alive,

I sve što je toliko suvo a i dalje živo,

we call desiccation-tolerant.

nazivamo otpornim na isušivanje.

In the desiccated state,

U isušenom stanju,

what seeds can do is lie in extremes of environment

seme može da leži u ekstremnim okruženjima

for prolonged periods of time.

u produženom vremenskim periodima.

The next time the rainy season comes,

Sledeći put kada dođe sezona kiše,

they germinate and grow,

one klijaju i rastu,

and the whole cycle just starts again.

i čitav ciklus krene ispočetka.

It's widely believed that the evolution of desiccation-tolerant seeds

Rašireno je verovanje da je evolucija semenja otpornih na isušivanje

allowed the colonization and the radiation

omogućila kolonizaciju i širenje

of flowering plants, or angiosperms, onto land.

cvetajućih biljki ili angiosperma, na zemlju.

But back to annuals as our major form of food supplies.

Da se vratimo na jednogodišnje biljke, koje su naše najveći zalihe hrane.

Wheat, rice and maize form 95 percent of our plant food supplies.

Pšenica, pirinač i kukuruz čine 95% naših biljnih zaliha hrane.

And it's been a great strategy

I to je bila odlična strategija

because in a short space of time you can produce a lot of seed.

zato što u kratkom vremenskom roku možete proizvesti mnogo semenja.

Seeds are energy-rich so there's a lot of food calories,

Seme je puno energije, zato tu ima mnogo kalorija,

you can store it in times of plenty for times of famine,

možete je čuvati kad ste siti i kad ste gladni,

but there's a downside.

ali ima i loša strana tome.

The vegetative tissues,

Biljna tkiva,

the roots and leaves of annuals,

korenje i lišče jednogodišnjih biljki,

do not have much

nemaju dobre

by way of inherent resistance, avoidance or tolerance characteristics.

urođene karakteristike otpornosti, izbegavanja ili tolerancije.

They just don't need them.

Jednostavno im nisu potrebne.

They grow in the rainy season

Rastu u sezoni kiše

and they've got a seed to help them survive the rest of the year.

i imaju seme koje im pomaže da prežive kroz ostatak godine.

And so despite concerted efforts in agriculture

I uprkos mnogim pokušajima u poljoprivredi

to make crops with improved properties

da se naprave usevi sa poboljšanim svojstvima

of resistance, avoidance and tolerance --

otpornosti, izbegavanja i tolerancije,

particularly resistance and avoidance

posebno otpornosti i izbegavanja,

jer smo imali dobre modele kako bi razumeli kako oni funkcionišu -

because we've had good models to understand how those work --

we still get images like this.

i dalje dobijamo slike poput ove.

Maize crop in Africa,

Usevi kukuruza u Africi,

two weeks without rain

dve nedelje bez kiše

and it's dead.

i nisu preživeli.

There is a solution:

Postoji rešenje -

resurrection plants.

oživljene biljke.

These plants can lose 95 percent of their cellular water,

Ove biljke mogu izgubiti 95% svoje ćelijske vode,

remain in a dry, dead-like state for months to years,

ostati u suvom, mrtvolikom stanju, mesecima i godinama,

and give them water,

i dajte im vode,

they green up and start growing again.

one pozelene i počnu opet da rastu.

Like seeds, these are desiccation-tolerant.

Kao i seme, one su otporne na isušivanje.

Like seeds, these can withstand extremes of environmental conditions.

Kao seme, mogu izdržati ekstremne vremenske uslove.

And this is a really rare phenomenon.

Ovo je zaista retka pojava.

There are only 135 flowering plant species that can do this.

Postoji samo 135 vrsta cvetajućih biljaka koje ovo mogu da urade.

I'm going to show you a video

Pokazaću vam video

of the resurrection process of these three species

procesa oživljavanja ove tri vrste

in that order.

u tom redu.

And at the bottom,

Na dnu,

there's a time axis so you can see how quickly it happens.

stoji vremenska osa gde možete videti koliko brzo se odvija.

(Applause)

(Aplauz)

Pretty amazing, huh?

Prilično neverovatno, zar ne?

So I've spent the last 21 years trying to understand how they do this.

Provela sam prethodnu 21 godinu pokušavajući da shvatim kako ovo rade.

How do these plants dry without dying?

Kako se ove biljke isuše a da ne umru?

Ja radim na raznovrsnim biljkama koje oživljavaju.

And I work on a variety of different resurrection plants,

shown here in the hydrated and dry states,

Ovde su pokazane u hidriranim i sušenim stanjima,

for a number of reasons.

iz različitih razloga.

One of them is that each of these plants serves as a model

Jedan je da svaka od ovih biljaka služi kao model,

for a crop that I'd like to make drought-tolerant.

za usev koji bih volela da postane otporan na sušu.

So on the extreme top left, for example, is a grass,

Skroz na levo, na primer, je trava

it's called Eragrostis nindensis,

naziva se Eragrostis nindensis,

it's got a close relative called Eragrostis tef --

ima bliskog rođaka zvanog Eragrostis tef

a lot of you might know it as "teff" --

mnogi od vas možda je znaju kao "tef",

it's a staple food in Ethiopia,

to je osnovna hrana u Etiopiji,

it's gluten-free,

bez glutena,

and it's something we would like to make drought-tolerant.

i to je nešto što bi voleli na napravimo tolerantnim na sušu.

The other reason for looking at a number of plants,

Drugi razlog zašto gledamo brojne biljke

is that, at least initially,

jeste da, barem u početku,

I wanted to find out: do they do the same thing?

želela sam da saznam da li rade istu stvar.

Do they all use the same mechanisms

Da li sve koriste iste mehanizme

to be able to lose all that water and not die?

da bi mogli da izgube svu tu vodu i da ne umru?

Zato sam izvršila kako mi nazivamo, pristup sistemske biologije

So I undertook what we call a systems biology approach

in order to get a comprehensive understanding

kako bi dobila obimno shvatanje

of desiccation tolerance,

otpornosti na sušu,

in which we look at everything

u kome bi gledali sve

from the molecular to the whole plant, ecophysiological level.

od molekula do čitave biljke na ekofiziološkom nivou.

For example we look at things like

Mi na primer gledamo stvari kao što su

changes in the plant anatomy as they dried out

promene u anatomiji biljke kada umiru

and their ultrastructure.

i njihovu ultrastrukturu.

We look at the transcriptome, which is just a term for a technology

Gledamo na transkriptome, što je samo izraz za tehnologiju

in which we look at the genes

u kojoj gledamo gene

that are switched on or off, in response to drying.

koji su uključeni ili ugašeni kao reakcija na sušenje.

Most genes will code for proteins, so we look at the proteome.

Mnogi geni će se promeniti zbog proteina, zato gledamo na proteome.

What are the proteins made in response to drying?

U šta su se pretvorili proteini pri reakciji umiranja?

Some proteins would code for enzymes which make metabolites,

Neki proteini se menjaju zbog enzima koji stvaraju metabolite,

so we look at the metabolome.

zato gledamo na metabolone.

Now, this is important because plants are stuck in the ground.

Ovo je važno, jer biljke ostaju u zemlji.

They use what I call a highly tuned chemical arsenal

Oni koriste, kako ja nazivam visoko podešen hemijski arsenal

to protect themselves from all the stresses of their environment.

kako bi se zaštitili od svih uticaja okruženja.

So it's important that we look

Važno je da gledamo na

at the chemical changes involved in drying.

na hemijske reakcije pri sušenju.

And at the last study that we do at the molecular level,

kod poslednjeg istraživanja na molekularnom nivou,

we look at the lipidome --

gledamo na lipidome,

the lipid changes in response to drying.

lipidne promene u reakciji sa umiranjem.

And that's also important

I to je takođe važno

because all biological membranes are made of lipids.

jer sve biološke membrane su sačinjene od lipida.

They're held as membranes because they're in water.

One se drže kao membrane zato što su u vodi.

Take away the water, those membranes fall apart.

Uzmite vodu i te membrane se raspadnu.

Lipids also act as signals to turn on genes.

Lipidi se ponašaju kao signali kako bi uključili gene.

Then we use physiological and biochemical studies

Zatim koristimo fiziološka i biohemijska istraživanja

to try and understand the function of the putative protectants

da pokušamo da razumemo funkciju pretpostavljene zaštite

that we've actually discovered in our other studies.

koju smo zapravo otkrili u drugim studijama.

And then use all of that to try and understand

I sve to da iskoristimo kako bi pokušali da razumemo

how the plant copes with its natural environment.

kako biljka savladava svoje prirodno okruženje.

I've always had the philosophy that I needed a comprehensive understanding

Oduvek sam mislila da mi je trebalo sveobuhvatno shvatanje

of the mechanisms of desiccation tolerance

mehanizma otpornosti na sušu

in order to make a meaningful suggestion for a biotic application.

kako bi imala značajan predlog za biotičku primenu.

I'm sure some of you are thinking,

Sigurna sam da neki od vas misle:

"By biotic application,

"Pod biotičkom primenom,

does she mean she's going to make genetically modified crops?"

da li ona misli na genetski modifikovane useve?"

And the answer to that question is:

I odgovor na to je -

depends on your definition of genetic modification.

zavisi od vaše definicije genetske modifikacije.

All of the crops that we eat today, wheat, rice and maize,

Sve useve koje jedemo danas, pšenica, pirinač i kukuruz,

are highly genetically modified from their ancestors,

veoma su modifikovani u odnosu na svoje pretke,

but we don't consider them GM

ali njih ne smatramo za GMO

because they're being produced by conventional breeding.

zato što su oni proizvedeni uobičajenim uzgojem.

If you mean, am I going to put resurrection plant genes into crops,

Ako mislite da ću da stavim gene oživljenih biljaka u useve,

your answer is yes.

onda je odgovor da.

In the essence of time, we have tried that approach.

U suštini, pokušali smo taj prilaz.

More appropriately, some of my collaborators at UCT,

Preciznije, neki od mojih saradnika na UCT-u,

Jennifer Thomson, Suhail Rafudeen,

Dženifer Tomson, Suhal Referdin,

have spearheaded that approach

su predvodili taj prilaz

and I'm going to show you some data soon.

i uskoro ću vam pokazati neke podatke.

But we're about to embark upon an extremely ambitious approach,

Uskoro ćemo naići na izuzetno ambiciozan prilaz,

in which we aim to turn on whole suites of genes

u kom ciljamo da uključimo gomile gena,

that are already present in every crop.

koji su već prisutni u svakom usevu.

They're just never turned on under extreme drought conditions.

Nikad se nisu uključili zbog uslova izuzetne suše.

I leave it up to you to decide

Na vama je da odlučite

whether those should be called GM or not.

da se treba nazivati GMO ili ne.

I'm going to now just give you some of the data from that first approach.

Sada ću vam dati samo neke podatke prvog prilaza.

And in order to do that

I kako bih to uradila,

I have to explain a little bit about how genes work.

moram još malo da objasnim kako geni funkcionišu.

So you probably all know

Verovatno svi znate

that genes are made of double-stranded DNA.

da su geni sačinjeni od dvolančanog DNK.

It's wound very tightly into chromosomes

Uvijen je veoma čvrto u hromozome

that are present in every cell of your body or in a plant's body.

koji su pristuni u svakoj ćeliji vašeg tela ili tela biljke.

If you unwind that DNA, you get genes.

Ako razmotate taj DNK, dobijate gene.

And each gene has a promoter,

Svaki gen ima pokretač,

which is just an on-off switch,

koji je samo prekidač,

the gene coding region,

deo kodiranja gena,

and then a terminator,

a onda i određivač

which indicates that this is the end of this gene, the next gene will start.

kojei pokazuje da je to kraj tog gena, gde će sledeći gen početi.

Now, promoters are not simple on-off switches.

Pokretači nisu samo prekidači.

They normally require a lot of fine-tuning,

Inače im treba puno podešavanja.

lots of things to be present and correct before that gene is switched on.

Dosta toga mora da bude prisutno i tačno pre nego što se gen uključi.

So what's typically done in biotech studies

Ono što se inače radi u u biotehničkim istraživanjima,

is that we use an inducible promoter,

jeste da se koristi indukovani pokretač,

we know how to switch it on.

znamo kako da ga uključimo.

We couple that to genes of interest

Nadovežemo to na gen koji nas zanima

and put that into a plant and see how the plant responds.

i stavimo to u biljku kako bi videli kako biljka reaguje.

In the study that I'm going to talk to you about,

I istraživanje o kom ću vam govoriti,

my collaborators used a drought-induced promoter,

moji saradnici su koristili pokretač koji oseti sušu,

which we discovered in a resurrection plant.

koji smo otkrili u oživljenoj biljki.

The nice thing about this promoter is that we do nothing.

Dobra stvar ovog pokretača je što mi ništa ne radimo.

The plant itself senses drought.

Sama biljka oseća sušu,

And we've used it to drive antioxidant genes from resurrection plants.

Mi smo to iskoristili da unesemo gene antioksidante od oživljenih biljki.

Why antioxidant genes?

Zašto geni antioksidanta?

Well, all stresses, particularly drought stress,

Svi napori, pogotovu napori vezani za sušu,

results in the formation of free radicals,

rezultira formacijom slobodnih korenja,

or reactive oxygen species,

ili vrste reaktivnog kiseonika,

which are highly damaging and can cause crop death.

koji su veoma smrtnonosni i koji dovode do umiranja useva.

What antioxidants do is stop that damage.

Antioksidanti sprečavaju to umiranje.

So here's some data from a maize strain that's very popularly used in Africa.

Ovo su podaci soja kukuruza koji se veoma koristi u Africi.

To the left of the arrow are plants without the genes,

Levo od strelice su biljke bez gena,

to the right --

desno,

plants with the antioxidant genes.

biljke sa genom antioksidanta.

After three weeks without watering,

Posle tri nedelje bez zalivanja,

the ones with the genes do a hell of a lot better.

one sa genima su mnogo bolje prošle.

Now to the final approach.

Konačan pristup,

My research has shown that there's considerable similarity

moje istraživanje je pokazalo da postoji velika sličnost

in the mechanisms of desiccation tolerance in seeds and resurrection plants.

u mehanizmu otpornosti na sušu i semenu oživljene biljke.

So I ask the question,

Zato postavljam ptianje,

are they using the same genes?

da li oni koriste iste gene?

Or slightly differently phrased,

Ili drugačije postavljeno,

are resurrection plants using genes evolved in seed desiccation tolerance

da li oživljene biljke koriste gene koji su evoluirali u seme otporno na sušu

u njihovom korenju i listovima?

in their roots and leaves?

Have they retasked these seed genes

Da li su oni geni semena zadali drugačije zadatke

in roots and leaves of resurrection plants?

u korenju i listovima oživljenih biljki?

And I answer that question,

Kako bih odgovorila na to pitanje,

as a consequence of a lot of research from my group

kao posledica mnogo istraživanja moje grupe

and recent collaborations from a group of Henk Hilhorst in the Netherlands,

i nedavnih saradnji grupe Henka Hilhorsta iz Danske,

Mel Oliver in the United States

Mela Olivera iz SAD

and Julia Buitink in France.

i Julije Butink iz Francuske.

The answer is yes,

Odgovor je da,

that there is a core set of genes that are involved in both.

postoji niz gena koji su evoluirali za obe stvari.

And I'm going to illustrate this very crudely for maize,

Sada ću ilustrovati ovo veoma grubo za kukurz,

where the chromosomes below the off switch

kada hromozomi ispod prekidača za isključivanje

represent all the genes that are required for desiccation tolerance.

predstavljaju sve gene koji su potrebni za otpornost suše.

So as maize seeds dried out at the end of their period of development,

Kako se seme kukuruza osušilo na kraju njihovog razvoja

they switch these genes on.

uključili su ove gene.

Resurrection plants switch on the same genes

Oživljene biljke su uključile iste gene

when they dry out.

kada su se osušili.

All modern crops, therefore,

Svi savremeni usevi

have these genes in their roots and leaves,

imaju te gene u korenima i listovima,

they just never switch them on.

samo ih nikad ne uključuju.

They only switch them on in seed tissues.

Uključuju ih samo za tkivo semena.

So what we're trying to do right now

Šta mi sada pokušavamo jeste da

is to understand the environmental and cellular signals

shvatimo signale okruženja i ćelija

that switch on these genes in resurrection plants,

koji uključe ove gene kod oživljenih biljki,

to mimic the process in crops.

kako bi replicirali kod useva.

And just a final thought.

I samo jos jedna misao,

What we're trying to do very rapidly

ono što pokušavamo veoma brzo da uradimo,

is to repeat what nature did in the evolution of resurrection plants

jeste da ponovimo šta je priroda uradila prilikom evolucije oživljenih biljki

some 10 to 40 million years ago.

pre neki 10 do 40 miliona godina.

My plants and I thank you for your attention.

Moje biljke i ja vam se zahvaljujemo na pažnji.

(Applause)

(aplauz)