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Adapting Lowland Rice to Climate Change – Thermal Stress Tolerance

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Adapting Lowland Rice to Climate Change – Thermal Stress Tolerance

Change Thermal Stress Tolerance

Breeding in the Sahel Region of West Africa

B Manneh, A Sow, P Kiepe and M Dingkuhn

CIMAC Conference, 7-9 Feb, 2011 University of Hohenheim, Germany

(2)

Major global rice growing areas and ecosystems

(3)

Rising Temperatures Rising Temperatures

• Temperatures rose by 0 6 ºC over most of

0.6 ºC over most of Africa in 20

th

century at 0.05 ºC/decade

• Five warmest years last century observed since 1988

since 1988

Mean surface air temperature anomalies for the African continent 1901 1998 (Hulme et al 2001) African continent, 1901–1998 (Hulme et al., 2001)

(4)

Declining rainfall in a semi

Declining rainfall in a semi--arid continent arid continent

• Most of Africa already Most of Africa already considered as dry land

• Many countries receive

• Many countries receive less than 500mm of rain annually

Map of rainfall zones in Africa Map of rainfall zones in Africa

(5)

Stress tolerance breeding strategy

• Screening of rice collections for the identification of stress tolerance

donors: Exploit the genetic diversity within O. glaberrima and traditional O.

ti sativas

• Development of breeding lines/populations

• Screening in controlled conditions and field trials

• Marker-Assisted Selection

• Evaluation in INGER and Participatory Varietal Selection (PVS) trials – Stability/adaptability, yield potential, farmers’ preferences

• Release through national programs

• Seed multiplication

(6)

Rice and climate adaptation Rice and climate adaptation

• Rice yields are low in Africa relative to other regions of the world

• Extent of yield loss due to climate change will differ between rice production systems (rainfed lowland, rainfed upland,

irrigated lo land mangro e s amp and deep flooded) irrigated lowland, mangrove swamp and deep flooded)

• Drastic changes in rainfall plus rising temperatures will g p g p aggravate abiotic stresses e.g. cold, heat, drought,

submergence and salinity

• Need for participatory, multidisciplinary research and

technology, development, evaluation and delivery through durable partnerships

durable partnerships

(7)

Effects of climate change on rice production Effects of climate change on rice production

• Extreme temperatures (cold and heat)

F d d h

• Frequent and severe droughts

• Floods

• High salinity

• Biotic stresses – blast brown spot RYMV Biotic stresses blast, brown spot, RYMV,

nematodes, etc

(8)

Heat stress in rice production systems Heat stress in rice production systems p p y y

All i d ti t d t h t t

• All rice production systems exposed to heat stress

• Heat stress leads to high spikelet sterility low tillering

• Heat stress leads to high spikelet sterility, low tillering, stunting and accelerated development

• Above 33 ºC sterility of rice drastically increases

• Severe yield reduction in sensitive genotypes

(9)

Daily temperatures at Ndiaye, Senegal in 2010

N D I A Y E ( 2 0 0 9 2 0 1 0 ) N D I A Y E ( 2 0 0 9 _ 2 0 1 0 )

5 0

e (°C) 3 0

4 0

Temperature

2 0

0 0 0 0 0 0

0 1 0

T m i n T m a x T m e a n

FEB MAR APR

JUL

0 1/ 0 1 /20 0

9

0 1/ 0 5 /20 0

9

0 1/ 0 9 /20 0

9

0 1/ 0 1 /20 1

0

0 1/ 0 5 /20 1

0

0 1/0 9 /20 1

0

• 240 genotypes screened across 4 sowing dates in Ndiaye, Senegal

• Daily minimum temps below 20°C from Dec-Mar

(10)

Sterility and growth duration of rice across Sterility and growth duration of rice across

different sowing dates in the Sahel different sowing dates in the Sahel different sowing dates in the Sahel different sowing dates in the Sahel

35 N22 160

20 25 30

80 100 120 140

re

IR64 Mean (244 vars)

5 10 15

Sterillity(%)

20 40 60 80

Days to matur

Sahel108 Chomrong

0

1 2 3 4

Sowing dates

0

1 2 3 4

Sowing dates

• Sterility highest on average for the April sowing date

• Growth duration longest for the Feb sowing date

(11)

Biomass production across sowing dates in Biomass production across sowing dates in

the Sahel the Sahel

250 300

ature 150

200 250

Days to ma

N22

SAHEL108 CHOMRONG

AVERAGE

0 50 100

Sowing dates

IR64 0 N22

1 2

3 4

• Highest biomass production observed in the February sowing date

(12)

Daily temperatures at Fanaye, Senegal in 2010

F a n a y e M a x i _ M i n i T e m p e r a t u r e

4 5

5 0 M a x i _ t e m p

M i n _ t e m p A v g _ t e m p

Mean flowering date

ure °C

3 5 4 0

Temperatu

2 5 3 0

0 0 0 0 0 0 0

1 0 1 5 2 0

Sowing date

1 /2 /2 01 0

1 /3 /2 01 0

1 /4 /2 01 0

1 /5 /2 01 0

1 /6 /2 01 0

1 /7 /2 01 0

1 /8 /2 01 0

• Fanaye with continental climate hotter than Ndiaye, Senegal

• On average Feb sowing leads to flowering in Apr-May

(13)

Heat Tolerance Nursery Heat Tolerance Nursery

Entry name Yield (kg/ha) Sterility (%) HM (cm) 50% FLO MAT (DAS) (DAS)

IR 197 46-28-2-2 11392 23 70 108 136

IR 50 9890 29 85 108 130

SAHEL 159 9782 25 93 100 139

SAHEL 134 9616 34 95 108 139

GIZA 176 9529 38 100 108 139

IR 1567 228-3-3 9299 20 87 108 136

GIZA 178 9271 40 95 108 139

GIZA 178 9271 40 95 108 139

SAMBALA MALO 9201 14 86 100 130

CR 547-1-2-3 9148 38 86 108 130

SAHEL108 (local check) 8753 38 86 83 109

N 22 (Tolerant check) 8743 24 106 124 147

Mean 6 914 28 101 103 132

CV 25.3 33.6 12.7

LSD 2848 15.7 22.08

• Four entries yielded above 9 t/ha and had less than 30% sterility (IR 19746-28-2-2, IR 50, IR 1567-228-3-3, CR 547-1-2-3)

• Sahel 159 promising with less than 30% sterility and yield of 9 8 tons/ha

• Sahel 159 promising, with less than 30% sterility and yield of 9.8 tons/ha

(14)

Opportunities for heat tolerance Opportunities for heat tolerance

breeding using African rice breeding using African rice breeding using African rice breeding using African rice

• O. glaberrima accessions found to have higher leaf transpiration rates than O sativa

transpiration rates than O. sativa

• Under non-moisture limiting conditions this helps to dissipate heat faster from leaves

dissipate heat faster from leaves

• Peak period for blooming in rice is 11.00 a.m. when

temperatures could exceed critical temperature of 33 ºC temperatures could exceed critical temperature of 33 ºC

• Blooming in O. glaberrima peaks at 7.00-8.00 a.m.

• Potentially very important escape strategy

(15)

Cold stress in rice production systems Cold stress in rice production systems p p y y

• Cold stress affects rice production in Africa through

Seasonal temperat re ariation Sahel region – Seasonal temperature variation – Sahel region

– Altitudinal temperature variation – mainly East Africa

• Cold stress leads to high spikelet sterility, low tillering, stunting and delayed development

• Below 20 ºC sterility of rice drastically increases

• Severe yield reduction in sensitive genotypes

(16)

Cold

Cold tolerance breeding tolerance breeding

12 day old seedlings grown in soil in metal trays immersed in cold water at 12° for 3 weeks

Temperature regulated screen house

(17)

Cold screening

Cold screening -- Seedling tolerance Seedling tolerance

7 8 9 10

Notes

3 4 5 6 7

bon bon

0 1 2

IR36 KOSH NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC NERIC SILEW Génotypes

HIHIKARI CA-L1 CA-L10 CA-L11 CA-L14 CA-L17 CA-L18 CA-L2 CA-L22 CA-L24 CA-L3 CA-L33 CA-L34 CA-L35 CA-L36 CA-L38 CA-L39 CA-L41 CA-L42 CA-L49 CA-L5 CA-L51 CA-L54 CA-L56 CA-L58 CA-L6 CA-L60 CA-L8 CA-L9 WAH

1ère notation 2ème notation

•12 day old seedlings grown in soil in metal trays immersed in cold water at 12° C for 3 weeks

• Four lowland NERICAs) (NERICA L-2, NERICA L-22, NERICA L-42 and NERICA L-9) found tolerant to cold at early seedling stage

tolerant to cold at early seedling stage

(18)

Field

Field evaluation evaluation in in participatory participatory varietal varietal trials trials

Rwanda cold tolerance PVS tolerance PVS

Madagascar cold tolerance PVS

•Promising breeding lines are evaluated in on-farm trials in participatory varietal trials

• Farmers’ selected lines are then submitted for national release as new varieties

(19)

MAB scheme for stress tolerance MAB scheme for stress tolerance

D

Donors:

Heat tolerance - N22

Cold - Silewah ( CTB-1, CTB-2)

Recurrent/Donor Recurrent //

BC

1

F

1

( , )

M202 (qCTS12a)

R i i t i ti l l l i ti

Selected BC

1

F

1

BC

1

F

1

/ Recurrent

Recipient varieties: popular local varieties Sahel 108, Sahel 201, BG90-2, Kogoni 91-1, NL19, Bouake189, Rassi, NERICA

BC

2

F

1

Selected BC

2

F

1

L-19, ITA212…

Routine use of MAB: transfer the QTLs

BC

2

F

1

/ Recurrent BC F

BC

2

F

2

Routine use of MAB: transfer the QTLs into adapted backgrounds through foreground and background selection

BC

3

F

1

Selected BC

3

F

1

BC

3

F

2

X

Seed increase, Evaluation, National release

(20)

Conclusions and perspectives Conclusions and perspectives

• Climate change already impacting negatively on livelihoods in Africa

• Need new sources of genes/alleles for developing rice varieties tolerant to major abiotic stresses in SSA j

• Diversity of rice gene pool should be exploited for new donors of genes/alleles for climate change adaptation g g p

• Need for greater involvement of climatologists and GIS

experts in developing climate-resilient rice technologies

experts in developing climate resilient rice technologies

(21)

Thank you!

Thank you!

Thank you!

Thank you!

Center of Excellence for Rice Research

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