Chapter 5: Measuring Diversity in Crops

Variety names

Agromorphological Traits

Biochemical and Molecular Markers

Focus Group Discussion for Characterizing Varieties

Mapping Spatial Distribution of Varieties on Farm

Encoding and Analyzing Participatory Data

Amount of diversity– Number of landrace names

– Farmers’ descriptors

– Agro-morphological traits

– Biochemical measurements

– Molecular markers

Measuring Diversity in Crops

J Bajracharya

Crop varietal diversity assessment on farm – the problem of variety names and distinctiveness

Diversity fairs Focus group discussions

Individual interviews

Farmer’s characterization of varieties at village level (FGD)

Distinguishing vs. Quality/PerformanceCategory Possible descriptive characters

Morphological Traits that can be used to distinguish varieties

colour of stem, leaf or seed shape of leaves, seed or fruit, disposition of flowers and fruits on the stems plant height pod/cob/ear/rhizome length or width earliness flowering time growth habit etc.

Performance and Quality Traits: Agronomic performance, Environmental/ecological adaptation, and use traits

yield and yield stability resistance to pests and diseases tolerance of water stress and harsh conditions tolerance to salinity tolerance to cold and high temperatures taste brewing quality storability cultural uses etc.

Nombres des

variedades

Moderna

/Local Color flor Lancha

tamaño

semilla

(grande =

2cm;

media=1cm;

pichino =<1

cm)

color of

grain

Size of plant

(grande=

>100cm; media

= 50 -100cm;

pichino =

<50cm)

color de

planta

Color

hojas Raiz precocidad

Vago selva M Blanca canario

Siete Billetes L precoz

Cocacho L rosa oscuras

Capitán L grande blanco Fuerte

Uña de Gato L grande

Garfio L/M Violeta Dura

Canario Bolón M grande amarillo

Matambre L

Chia M

Farmer’s characterization of varieties at village level

Descriptive traits(FGD)

品种的名字

地方品种/

现代品种traits/criteria

Trait values

Variety

name

Local or

Modern

Example of quality traits data: Nepal case study

Descriptors on sensory

aspects

- good / poor taste

- better / less tasty than…

- bitter

- juicy

- soft

- aromatic rice

- tasty flour

...

Descriptors on food

processing and

appreciation of some

traditional recipes

- good to make bread,

salad, pickles, rice

pudding...

- good for several traditional

dishes

- need to be boiled

- A part of the corm is not

edible

…

Descriptors on the health

value attributed to the

landraces

- easily digestible

- nutritious

- content feeling after

consumption

- medicinal value

- good diet for women after

child birth

- good diet for low blood

pressure patient

- causes heart problem,

gums problems

…

Source : Baseline reports of the in situ project in Nepal Data on preferred and unpreferred traits

Many farmers' descriptors are related to the nutritional value of landraces

Hints for further investigations

Trait values

Variety

Name

Farmers’ descriptors

organized by rapporteurs

Farmer Descriptors of the varieties they brought to the

focus group

Names over represent diversity

Names under-represent diversity

Lack of specific names under-represent diversity

0

Community

Village

Nearest Hoseholds

Consistency of landrace identification over space

Province

Nam

es C

on

sisten

cy

Tra

its

Co

nsi

sten

cy

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

Sidi Senoun Bouajoui Hadarine El Jir Aïn Barda Ghiata-Al-

Gharbia

Oued Amlil

Villages (ranked on geographic distancein km from Ain Kchir)

Consis

tency index r

Name

Trait

Exercise

• On Farm

• On Research Stations

Agronomic measurements

Agromorphological characterization and disease damage of maize varieties from Sichuan

● The question

– How much phenotypic difference is there among maize varieties?

– Are hybrid significant different from landraces?

● With what data?

– Morphological measurements (quantitative data)

● Which statistics

– Multivariate analysis

– UPGMA

Experiment materials

• Totally 19 maize varieties were tested, including 12 local varieties and 7 modern varieties

• These varieties were collected from– Xishuangbanna of Yunnan

– Zhaojue of SIchuan

Experiment design

• For maize, each variety was planted in a 12m2 plot

• The varieties (plots) were randomly arrangedin experiment field

• 3 replicants were placed in 3 each site

V2 V5 V3

V4 V9 V8

V7 V1 V6

V6 V7 V8

V3 V9 V5

V1 V4 V2

V1 V4 V9

V5 V6 V2

V8 V3 V7

Experiment design

• For maize, 17 agronomic

traits were investigated

– Plant height, Stem

diameter,Plant type

– Ear height, Ear length, Ear

width, Length of ear head

without grain

– Head progeny row, Numbers of

grains per row, Full seed rate,

Pair of spike, Spike shape

– Thousand-grain weight, Grain

color, Grain type, Waxy or not

Descriptive statistics

Explore phenotypic diversity by PCA

Are maize varieties phenotypically different?

MANOVA test can be used to test this observation

Explore phenotypic diversity by PCA

Are hybrid different from landraces?

MANOVA test can be used to test this observation

Explore phenotypic diversity by PCA

A cluster analysis using morphological distances can help to show differences among varieties and among hybrids and landraces.

It also tell us how much varieties are different

Temperate fruit tree variety diversity assessed in Kazakhstan,

Kyrgyzstan, Tajikistan, Turkmenistan, Uzbekistan

Diversity level (on farm):

• Apple – 239

• Apricot – 221

• Grapevine - 158

Middle maturing

Early maturing

Managing production under increased unpredictable of frost

yes

How diverse are the apple varieties? We can cluster them according to

farmer recognizable (phenotypic, agronomic and adaptive) characters.

Late maturing

Apple diversity - Uzbekistan

no

Yield Disease resistance

Drought resistance Good taste

Exercise

Biochemical and Molecular

Paolo Colangelo

Distribution of Diversity Across the Landscape

• Across households

• Across landscapes

Where - Distribution of diversity: Rare vs. Common -- Rice in Nepal

Rice landraces grown in large

area by many households

Rice landraces grown in large

area by few households

Rice landraces grown in small

area by few households

Rice landraces grown in small

area by many households

(Rana et al., 2000)

Distribution of diversity at household level: many/few HHs and large/small area in Kaski, the mid-hill ecosite

Kaski -- Percent HH X Percent area

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60

Percent HH growing Landrace (Total 173)

Pe

rce

nt

Are

a C

ov

ere

d (

To

tal 7

9.0

9 h

a)

Series1

Large

Small

ManyFew

-5.5

-5

-4.5

-4

-3.5

-3

-2.5

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

-6 -5.5 -5 -4.5 -4 -3.5 -3 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 3 3.5 4

Principal component 1

Pri

ncip

al c

om

po

ne

nt 2

YaxcabaNeighbor comm.YucatanQ. Roo Campeche

(B, PH, LBS, TNTB,

and EL)

(LAC, CSIL, ED, PD, and

KT)

Chavez et al., 2000

Agronomic characters of 314 maize populations from Yucatan Peninsula

Yaxcaba Rest of Yucatan Peninsula

(3 Provinces)

Neighbour Village

Distribution of agromorphic trait diversity across the landscape

Sbai Foul

1.5 ha

Foula

1.0 ha

Foul Khal

0.5 ha

Total area planted to Faba Bean = 3.5 ha

Faba Bean

Variety

Names

Area

covered % area

Sbai Foul 1.5 ha 0.43

Foul Khal 0.5 ha 0.14

Foula 1 ha 0.29

Ibaoune 0.5 ha 0.14

Ibaoune

0.5 ha

Collecting HH Variety Diversity

• Exercise