Challenges to sustainable potato productionin a changing climate: A research

perspective

R. Quiroz, A. Posadas, C. Yarlequé, H. Heidinger, C. Barreda, R. Raymundo, C.Gavilán, M. Carbajal, H. Loayza, H. Tonnang, J. Kroschel, G. Forbes, and S. De

Haan.

Centro Internacional de la Papa

August 15th 2011Conference presented at the 95th Annual Meeting of the Potato Association of America. Wilmington NC

Symposium - Breeding for Sustainable Production in a Changing ClimateUnderstanding the Physiological Basis of Genetic and Environmental Interactions

Contents

• Potato in variable environments

• CC-Potato - Literature findings

• Summary of perceived research gaps

• Addressing research gaps at CIP

• Farmers adaptation strategies in theAndes and tradeoffs

Temperature

Water & Nutrients

Light & CO2

Where is potatoProduced?

Potato acreage

It is about climate change w/oforgetting climate variability

The concentration ofGHGs is rising

Long-term implicationsfor the climate and for

crop suitability

Areas where maximum temperature during the primary growing seasonis currently < 30°C but will flip to > 30°C by 2050

Areas where rainfall per day decreases by 10 % or more between 2000 and 2050.

DIRECT EFFECTS:elevated levels of Carbon dioxide on potato

crops

Leaf Processes Increased CO2

Photosynthetic rate

Stomatalconductance

Leaf Protein,Chlorophyll content

Starch / CHO content

•When exposed for a short period -substantial increment

•Down regulation when grown continuouslyin elevated CO2

•Decreases at elevated CO2

•Expected to increase WUE

•Contradictory responses, probablyassociated to cultivar differences

•Increases with long-term exposure toelevated CO2

Effect of elevated levels of Carbon dioxide onpotato crops

Process Increased CO2

Changes in plant growthand development

Effects on crop yield

Effects on tuber quality

•Stimulates both above-and below-groundbiomass (early growing season)

•Period of active plant growth endsprematurely

•Senescence begins earlier

•Limited growth rates towards the end ofgrowing season

•Tuber yield stimulated and magnitudevaries with cultivar and growing conditions

•Increase number of tubers

•Increased tuber DM & starch content

•Reduced tuber N and glycoalkaloidcontent

Effect of elevated Temperature on potato crops

•Elevated temperatures seems to reduce tuber initiation

•Temperature above the desired ones reduce the photosynthetic efficiency, thusreducing potato growth

•High temperature may also reduce the ability of the plant to translocatephotosynthates to the tuber

•Elevated temperature increases DM partitioning to stems but reduces root,stolon, tuber and total DM and total tuber number

•Offset the CO2 fertilization effect

INDIRECT EFFECT: potato pests and diseases

Baseline w/o crop protection 75 % ofpotato production today would belost to pests

Major factors likely toinfluence plant diseaseseverity and spread

•increased CO2,•heavy and unseasonal rains,•increased humidity, droughtsand hurricanes,•warmer winter temperatures

Changes in theclimate are expectedto produce

•alterations in the geographical distribution ofspecies,

•increase overwintering,

•changes in population growth rates,•increase the number of generations perseason,

•extension of the development season,

•changes in crop-pest synchrony,

•increase risk of invasion by migration pests,

•may cause the appearance of newthermophilicspecies,

•changes in the physiology ofpathogens/insects and host plants,

•changes in host plants resistance toinfection/infestation,

•critical temperature/infection threshold,•modification of pathogen aggressivenessand/or host susceptibility

Knowledge gaps and research priorities:

Experimental analyses and model simulation to quantify:- Effect of increasing CO2 on crops other than cereals, includingthose of importance to the rural poor (e.g. local potato cultivars)- Interaction between crop yields and other factors of production(pests, diseases, weeds, etc.) under climate change conditions

- Impact of climate extreme events on crop yieldsReduce and quantify uncertainties of future prediction:

- Generate reliable data to test GCMs through hindcasting- Improve the spatial resolution of climate predictions

Develop tools to evaluate adaptation strategies at differentspatial levels (cropping, farm, region)

- Link climate-pathogens-hosts interactions across scalesEvaluate actual applicability of adaptation strategies:

- Quality of seeds- Cost and benefits (economic, social, environmental)- Role of new technology (e.g. biotechnologies, fertilizers, etc.)- Tradeoffs analyses

CIP advances on potato modelingy S. Tuberosum - tuberosum - andigena y S. Ajanhuiri y S. juzepczukii

Light

Light

Interception

DMLUE (PAR—

Kg DM.ha¨¹.d ¨¹

Tubers

)Photosynthetic

Apparatus

T GC LAI

Light Reflectance

Roots Stems Leaves

Improving model inputs

GB R NIR

RS data for helping select tolerant potato cultivars

NDVI0-0.1

0.1-0.20.2-0.30.3-0.40.4-0.50.5-0.6

Fresh yield (t/ha)<16

>24

60 60

50 50

40 40

30 30

20 20

10 10

0 0

1 2 3 4 5 6 7 8 9 10 1112 1 2 3 4 5 6 7 8 9 101112

Plot Plot

Normal irrigation

Deficit irrigation Terminal drought

MRI- Potato tuber scanning

MRI -potato root scanning

Coping with limited spatial-temporal coverage of climate data

From RS data to rainfall

(ppm)

HUANCANE

50

40

30

20

10

0

1-Jan-99 20-Jul-99 5-Feb-00 23-Aug-00 11-Mar-01 27-Sep-01 15-Apr-02 1-Nov-02

Días

Source: Yarlequé et al., 2007

Andean Farmers: Adaptation strategies and potential tradeoffs

20th Century Climate Change in Tropical Andes

Variable Assessment

Temperature Average warming of 0.09-0.15◦C decade−1; western

slopes>highlands>eastern slopes

Relative humidity (near Increased 0 - 2.5 % decade−1;surface levels)

Precipitation Little change in the latter half of20th Century. Some increments inEcuador, NW Argentina andBolivian lowlands

Source: Vuille et al., 2003

Projected Climate: Andes

Late Blight (LB)

� Warmer temperatures withsome humidity in highergrounds will increase thepresence of potato late blight.

� High incidence of LB in thefuture (2050) above 3000masl (highlighted in the map)where it is virtually absenttoday

Potato tuber moth (PTM)

� PTM is actually present ininterandean valleys and thecoastal areas of the Andes

� PTM is expected to climb aswell due to climate change

60

45

30

15

0

50

40

Potato species

Solanum juzepczukii (juz)Solanum tuberosum ssp. Andigena (and)Solanum tuberosum ssp. Tuberosum (tub)Solanum phureja (phu)A B CSolanum acaule (acl)

30

20

10

0

A

50

40

30

20

10

0

A B C

B C

50

40

30

20

10

0

A

50

40

30

20

10

0

A B C

B C

Cultivar and progenitors

(A) Lukijuz 100%

(B) Gendarmeand 100%

(C) SajamaHybrid

and: 25%tub: 50%

phu: 12.5%acl 12.5%

Period

1965-19751976-19851986-19951996-2005

As temperature and presence of pest increase in theAndes Potatoes are planted in higher grounds

1975:(4000-4150msnm)

2005:(4150-4300msnm)

S. De Haan & H. Juarez, CIP (2008)

Putting pieces together for a hypothetical example:Changes in potential potato (improved and native) in Peru: 2000-2050

Sampling-transect to assess carbon contents and stocks in Southern Peru.Source: Segnini et al., 2010

Carbon stocks in diverseAndean soils

Peatlands and otherland uses in theAndean highplateau

Potential loss of soil carbon stocks due to croppingpeatlands and grasslands in Peru & Bolivia

Peatlands to potato

350

300

250

200

150

100

50

0

2000

Bolivia

Scenarios

Peru

2050

Grasslands to potato

12000

10000

8000

6000

4000

2000

0

2000

Bolivia

Scenarios

Peru

2050

The challenge(Climate smart agriculture)

Potato agriculture that sustainably increases productivity, resilience(adaptation), reduces/removes greenhouse gases (mitigation), andenhances achievement of national food security and developmentgoals.