SEED PRODUCTION IS NOT NEW DOMESTICATION …...DOMESTICATION OF OUR CULTIVATED PLANTS JENS WEIBULL,...

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SEED PRODUCTION IS NOT NEW –DOMESTICATION OF OUR CULTIVATED PLANTS

JENS WEIBULL, Swedish Board of AgricultureROLAND VON BOTHMER, NordGen

The first agriculture

The Fertile Crescent

flaxlens bean

Domesticationstarted

10 000 BP

wheat

barley

Maize

Sorghum

Rice

Wheat

?

Grasses became cereals

10 000

9-10 0006 -7 000

7-8 000

(years BP)

Most cultivated plants are very old!

Egypt had a highlydeveloped agriculture

3-4 000 years ago

Allium sativum is diploid (2n=16) but almoststerile and very seldom sets seeds. It is known since

around 7 000 BP.

Garlic in a tombof a Farao...

… identical topresent types and the origin is not

known!

Newer crops are few

18th-19th centuries- sugar beet- canola/rape seed- strawberry- rubber- oil palm

20th century- sweet lupin- sunflower (oil)- triticale- salix- forages- ornamentals

CROP PLANT EVOLUTIONIN THREE PHASES

• Domestication

• Migration, selectionand adaptation

• Modern plant breeding

CROP PLANT EVOLUTION Phase 1

Domesticationof Zea mays

ZeaTripsacum

• Domestication• Migration, selection and adaptation• Modern plant breeding

DOMESTICATION

Transfer from the wild state to an agricultural ecosystem;large genetic changes during a short period

−> macroevolution

wild barley landrace modern cultivar

DOMESTICATION, cont’d

Major genetic changes:

• From cross- to self pollination• Loss of seed dispersal• Even germination and maturation• From perennialty to annuality• Changed growing habit

Efficient dispersal by animals

Wild barley

toughbristles

brittlerachis

An effective dispersal mechanism

One day’s harvest of wild barley seeds(Hordeum murinum) in the socks!

Modern six-rowedbarley

has lost its dispersalmechanism

CROP PLANT EVOLUTION Phase 2

• Domestication• Migration, selection and adaptation• Modern plant breeding

A barley landrace in Pakistan

Rapid migration – 6 000 years in Scandinavia!

Spread of agriculture

ADAPTATIONGradual development; minor genetic changes

in many genes over a longer period −> microevolution

Natural and conscious selection

Barley from Bhutan

Locally adapted landraces developedto new edaphic and climatic conditions

Barley from N Pakistan

A wheat field in NorthernPakistan, 4 000 m a.s.l.

Many species show extreme adaptation…

CROP PLANT EVOLUTION Phase 3

• Domestication• Migration, selection and adaptation• Modern plant breeding

GRAMINOR AS, Norway

What is the origin of our crops???

some examples

Barley

Domestication of an ancient crop, with a ”simple” evolutionary history

The progenitor of barley, Hordeum vulgare ssp. spontaneum,

still grows wild in SW Asia. It is a diploid,self-compatible taxon and fully fertile

in crosses with barley

Wild barley spikes at maturity

Ssp. spontaneum has large, heavy and nutriousseeds which were gathered long before the

domestication of barley

Grain dispersal of wild barley

wheat

Domestication of an ancient crop,with a complex evolutionary history

Domesticationof bread wheat,

Triticum aestivum

emmer, durumX

Einkorn

Bread wheat

AABBDD

AA BB?

X

X

Aegilops speltoides Tausch(goatgrass)

AABB

Emmer, durum

DD

X Ae. squarrosa

Domestication of a secondary crop

outbreeding

Rye(Secale cereale)

• rye

• oats

Domesticationof a secondary

crop:

Rye

??5-6 000 BP

Slash and burn agriculture developed early, and persisted in middleand north Scandinavia almost to the 20th century

Agriculture developed

Eero

rnef

elt,

18

93

Turnip,Brassica rapa ssp. rapa

CROPS IN THE SLASH AND BURN SYSTEM

Rye, Secale cereale

kales, cabbages, turnips, mustards, rapeseed/canola

??

Domestication of ”middleaged” crops –a complex (hi)story

– the genus BRASSICA

Cabbage Brusselssprouts

Kohlrabi Kale Broccoli Cauliflower

lateral buds

terminalbuds stem leaves stems &

flowers

flowerclusters

Wild Brassica

Selection for various types in Brassica

The Brassica triangle of U

Black mustard,B. nigra

Indian mustard,B. juncea

Ethiopian mustard,B. carinata

Wild kale,B. oleracea

Turnip,B. rapa

Oilseed rape,B. napus

2n=16BB

2n=34BBCC

2n=18CC

2n=38AACC

2n=36AABB

2n=20AA

A recent industrial crop –with a long evolutionary history

SUGAR BEET

The beets are of European origin –the ancestor is the wild sea beet

Beta vulgaris ssp. maritima

Sugar beet

Leaf beet

Chard(mangold)

Red beet

Fodder beetsincl. mangels

Sugar beet

Beta maritima

ca 1500

Pre-Greek time (ca 4 000 BP)

ca 1780

EVOLUTIONIN BETA

Progress of sugar beet breeding

2012

Increase in sugar contentover two centuries

A recent, ”man-made” horticultural crop

STRAWBERRY

Evolution of strawberry

Wild European strawberryFragaria vesca 2n=2x=14

The Swedish father of botany knew only the wildstrawberry, Fragaria vesca, which he praised:it was an important cure for many illnesses(which he suffered from)

Carl Linnaeus

Evolution of strawberry, Fragaria x ananassa

F. virginiana(2n=8x=56)

F. chiloensis(2n=8x=56)

1714

F. x ananassa(2n=8x=56)

1750

Do we have any native Nordic crops?

Forage grasses!

CocksfootDactylis

glomerata

Smooth meadow grassPoa pratensis

TimothyPhleumpratense

Meadow fescueFestuca pratensis

Do we have any native Nordic crops?

Forage legumes!

Red cloverTrifolium pratense

White cloverTrifolium repens

Alsike cloverTrifolium hybridum

Do we have any native Nordic crops?

Currants!

Ribesnigrum

Ribesrubrum

We have great diversity in several cropsnot originally native to us

Barley

Apple

Oat

Cabbage

Horse radish

The evolutionary processes of

• Domestication• Migration, selection and adaptation• Plant breeding

have created a great genetic diversity in our cropsduring the long history of agriculture

SMALL CROPS ARE STILL IN CULTURE…..but decreasing rapidly

A case study….

SMALL CROPS ARE STILL IN CULTURE…… but what is this??

Lentisk, Pistacia lentiscus

Mastix is only cultivatedin the southern part

of the island ofChios in Greece

THANK YOU!!