EFFECTS OF TEMPERATURE ON IN SITU GROWTH AND DEVELOPMENT OF CIP POTATO CLONES IN

BURUNDI

D. Harahagazwe, J.F. Ledent and G. Rusuku

8th African Potato Association Conference

Cape Town, South Africa

6 – 9 December 2010

INTRODUCTION

Zoom on Burundi

• Inland country

• 27834 km2

• 8,17 millions inhabitants

• Density: 294 inhabitants/km2

• Pop. growth rate: 3,9 %

• Life expectation: 45 years

• GNR: 100 $/inhabitant/year

• Agriculture: 90,6 % of land

• Agriculture: 34,8 % of GDP

• Food insecurity (67%)

4

Four scenarios

– Increase productivity (clean seed, fertilizers and pesticides)

– Promote importation of ware potatoes (ex. 6000 t/an from Rwanda)

– Introduce potato crop in warm areas (Imbo – region > 5000 ha)

– Different combinations of the three other scenarios

Challenges

• Potatoes as a temperate crop

• Cropping temperatures : 5 à 25°C

• Max. temperature: 28°C

• Variety tolerance: 30°C

• Imbo as warm tropical climate: >28°C/18°C

Temperature in Lowlands (Imbo region)

Mugerero 2005

Time (day number)

200 220 240 260 280 300

Daily

tem

pe

ratu

re (

°C)

14

16

18

20

22

24

26

28

30

32

34

Minimum

Maximum

Average

Mugerero et Mparambo (2006)

Time (day number)

180 200 220 240 260 280 300D

aily

tem

pera

ture

(°C

)15

20

25

30

35

Minimum, MUG06

Minimum, MPA06

Maximum, MUG06

Maximum, MPA06

Average, MUG06

Average, MPA06

Expected effects of temperature

• Total biomass reduction (stomatal conductance)

• Harvest index reduction (hormonal action)

• Incidence and severity of pests and diseases (disease triangle)

Specific objectives

– Determine temperature effects on the different potato agrophysiological parameters

– Determine the phenotypic behavior of CIP material in heat conditions

MATERIALS AND METHODS

TEAM WORK

Experimental sites and years

Parameter Gisozi Ryansoro

Season Dry season Dry season

Latitude (S) 3°34’ 3°47’

Longitude (E) 29°41’ 29°46’

Altitude (masl)a 2091 1833

Global radiatione

(MJ.m-2

.j-1

)

9.06 -

Type of soil Peatland Peatland

8.63 8.63

Hygroxero-

ferrisold

Mparambo Mugerero

Dry season Dry season

2°50’ 3°15’

29°04’ 29°18’

892 801

Sites: Lowlands: Mugerero and MparamboHighlands: Ryansoro and Gisozi

3 years: 2005, 2006 and 2007

Material, design and crop management

• Genotypes: • Clones: CIP01 to CIP05,

• Varieties: NDINA (Ndinamagara), RUHA (Ruhanyura) and VICTO ( Victoria)

• Design: RCBD (3 - 4 reps; 80 cm x 30 cm; 20 to 30 plants/plot

• Crop management:• 2 t of lime/ha

• 500 g of cow manure/hill

• 14,3 g of NPK/hill, equivalent to 100-150-100 NPK formula

Data collected

– Plants emerged

– Ground cover

– Plant height

– LAI

– SLA (ImageJ technology)

– Pests and diseases

– Fresh and dry weight of leaves at harvest

– Fresh and dry weight of tubers at harvest

– Harvest index

– Tuber size and weight

– Dry matter concentration

– Etc…

Data analysis

• 2 levels of analysis :

– Per site and per season (environment): ANOVA (Gomez and Gomez, 1984)

– Across environments: AMMI (Additive Main

effects and Multiplicative Interaction Model) (Gauch, 1992)

∑ +++++=n gergeengnneggerY ερηζλβαµ

ANOVA PCA

RESULTS AND DISCUSSION

Statistics

Parameter Environment (E) Genotype (G) G x E

Dry matter concentration

*** *** ***

Emergence rate *** *** NS

Plant height ** *** ***

Ground cover *** *** NS

Tubers/plant *** *** **

Proportion of consumer tubers

*** *** NS

Average tuber weight

*** *** *

Fresh tuber yield *** *** ***

Dry tuber yield *** *** ***

Harvest index *** *** ***

Tuber number per plant (ANOVA)

Site

GIS

07

RYA07

MPA07

MPA06

MU

G06

MU

G05

Num

ber

of tu

bers

per

pla

nt

0

10

20

30

40

Mean

CIP01

CIP02

CIP03

CIP04

CIP05

NDINA

RUHA

VICTO

Tuber number per plant (AMMI)

VICTO

CIP01

RUHA

RYA07

NDINA

MUG05

CIP05

MUG06MPA07

GIS07

CIP04

CIP03

CIP02

MPA06

25

2

20

0

15

-2

10

-4

5

Tuber number per plant

1

-3

30

-1

IPC

A 1

Dry tuber yield (ANOVA)

Site

GIS

07

RYA07

MPA07

MPA06

MU

G06

MU

G05

Dry

tuber

yie

ld (

t.ha-1

)

0

2

4

6

8

10

12

Mean

CIP01

CIP02

CIP03 CIP04

CIP05

NDINA RUHA

VICTO

7.5

2.1

Dry tuber yield (AMMI)

VICT O

CIP01RUHA

RYA07

NDINA

MUG05

CIP05

MUG06

MPA07

GIS07

CIP04

CIP03

CIP02

MPA06

7

0.5

6

-0.5

5

-1.5

432

1.0

Dry tuber yield (t/ha)

8

-1.0

9

0.0

IPC

A 1

(S

QR

(t/h

a))

Harvest index (ANOVA)

Site

GIS

07

RYA07

MPA07

MPA06

Ha

rve

st in

de

x

0,0

0,2

0,4

0,6

0,8

1,0

Mean CIP01

CIP02 CIP03 CIP04

CIP05 NDINA

RUHA VICTO

0.77

0.54

Pests and diseases

• Highlands:

– Late Blight (clone CIP03 and CIP04)– Bacterial Wilt

• Lowlands

– No Late Blight observed (> 22°C)– Mainly Fusarium (Wilt and Rot) especially clone CIP02 with 25% of

plant wilt– Few plants with Black Leg/Soft Rot

• All sites

– Alternaria– Aphides

LESSONS LEARNT

Ecology

– Average temperature:

– Cycle length:

– Dry tuber yield:

– Fungal diseases:

– Bacterial diseases:

� Conditions for potato cropping

Cool Warm

17°C 25°C

Long Short

11.6 t/ha 2.1 t/ha

Late Blight Fusarium

Bacterial Wilt Black Leg/Soft rot

Optimal Sub optimal

However, the genetic variability was expressed in warm climates:

– 3 clones (CIP01, CIP03 and CIP05) found heat tolerant

– High potential for

• Current tropical and subtropical warm areas and

• Current cool but heating up areas due to climate change

THANK YOU VERY

MUCH

MUITO OBRIGADO

MURAKOZE

CANEMERCI

BEAUCOUP

Contact: dharahagazwe@yahoo.fr