1. New elite Potato clones with heat tolerance,
late blight and virus resistance to address
climate change
Manuel Gastelo, Luis Diaz, Juan Landeo, Merideth Bonierbale
APA 2013 – 9th Triennial Conference
June 30 – July 04, 2013 Naivasha ‐ Kenia

2. Introduction
Potato production in developing countries is expanding to warmer
environments in search of income opportunities and food security,
climate change is also already affecting weather patterns in traditional
potato growing areas
The International Potato Center has developed a new population
denominated LBHT (late blight resistance plus heat tolerance), with
the objective to obtain clones with:
Resistance to late blight
Heat tolerance
Mid‐early maturity (90 days).
Resistance to PVY, PVX
Drought tolerance
Good quality and agronomic traits

3. Causes of Climate Change
Industrial activity: from the early nineteenth
century by the use of fossil fuels (CO2)
Methane gas (CH4): from intensive livestock
production .
Nitrous oxide (N2O): used in aerosols
incandescent lamps .
With this combination of factors and events that
contribute to climate change, what happened in
centuries before, now occurs in decades.
Effects of Climate Change
Greenhouse effect - Global warming
Drought

4. Effects of Climate Change on Potato
The rising temperatures and the
appearance of new pests and diseases
affecting the production of potato crop
in the world.
The temperature rise from global
warming is an ongoing process and with
negative effects both for the production
of traditional potato varieties as for new
areas. So CIP decided to look for new
varieties adapted to heat.

5. Materials and Methods
Population LBHT: was developed using
Recurrent phenotypic selection, with four
season cycle Season II
1,000 ‐ 3,000
Screening under field conditions :
10 hill‐plot: San Ramon ( Jul – Oct)
Season IV
50 ‐100
Screening under field conditions: LB, Heat
San Ramon, Oxapampa, Majes, La Molina
Season I
20,000 sedlings planted under
Greenhouse for screening by heat
San Ramon, Summer (December –
April)
Season III
100‐ 200
Screening under field conditions: LB,
Heat San Ramon, Oxapampa, Majes, La
Molina
Selected clones (Parents)
Stability, Varieties
Virus resistant test, drought
Clean virus for export
San Ramon.‐ a warm rain forest
environment at 800 m
Average temperatures in experiments
during tuberization under field conditions,
were 21ºC at night and 27ºC at day
Day
Night Night

6. # Locality
Altitude
masl
Latitude Growing seasons
Agroecological
zone Selection for
1 San Ramon 800 11° 08´ S Dry and Warm
Mid elevation
tropics Heat
2 La Molina 240 12° 05´ S Spring ‐ Summer
Lowland tropics Heat
3 Oxapampa 1850 10°37´ S Spring ‐ Summer
Mid elevation
tropics Late blight
4 Majes 1294 16° 28´ S Spring ‐ Summer
Mid elevation
tropics Heat, Drought
Research sites in Peru and the potato growing seasons
Oxapampa LB 1850 mals San Ramon Heat 800 mals
La Molina Heat Spring Season 240
mals
Majes Heat Spring – Summer Season
1294 mals

7. Screening for virus resistence
All selected clones were screened for resistance to PVX and PVY by
mechanical inoculation and grafftig in the greenhouse and index by
ELISA
For drought tolerance comparative fields with normal and
restricted irrigation were performed, for seletcion of clones was
used drought tolerance index DTI
Screening for Drought tolerance

8. Selection of clones with resistance to late blight were using scale of
susceptibility development by Yuen and Forbes in 2009
Screening and Selection for Late Blight under field conditions

9. Yield Stability Analysis
2012 – 2013 : 61 advanced clones were assessesd for tuber yield in SRA, LAM ,
MAJ under high temperatures
All trials were conducted in a simple lattice design 8x8 with 20 plants per plot
Two varieties were used as controls : Desiree, heat tolerant and Amarilis,
heat sensitive
Traits measured : Plant vigor, maturity, Marketable tuber number, Marketable
and Total tuber yield
The experiments were harvested at 90 days after planting
Stability analyiis was performed with AMMI stability model
The results of the AMMI model were interpreted on the basis of two AMMI
graphs for principal components and tuber yield

10. San Ramon La Molina Majes San Ramon La Molina Majes
Replications 1 31.245* 27.161 26.757 57.682** 10.911 57.228*
Genotypes 63 65.067** 138.491** 167.078** 68.459** 127.172** 184.397**
Block/Replications 14 3.346 21.752 13.096 4.384 30.391* 13.842
Error 49 2.793 14.402 9.882 3.009 12.745 10.785
C.V. % 9.8 14.5 16.8 9.5 12 16.5
Total tuber yield tha
‐1
Means Square
Source of variation df Marketable tuber yield tha
‐1
ANOVA for Marketable and Total tuber yield (tha‐1) in three environments 2012‐2013
Results
Source of variation df
Means Square
Marketable tuber yield Total tuber yield
Replications/Environments 3 28.39* 41.90*
Block/Replications/Environments 42 12.73 16.20*
Treatments 191 153.63 177.78
Environments 2 2997.12** 5007.20**
Genotypes 63 200.92** 200.30**
Genotypes x Environments 126 84.86** 89.90**
PCA1 64 118.01** 134.53**
PCA2 62 51.92** 45.88**
Pooled error 147 9.03 8.80
C.V. % 15.20 14.31
Combined ANOVA for AMMI model for Marketable and Total tuber yield (tha‐1)

11. AMMI Yield Stability Analysis
Stable Clones
Low tuber yield
Stable Clones
High tuber yield
Unstable Clones
Low tuber yield
Unstable Clones
High tuber yield

12. Tuber yield of 40 elite clones under San Ramon conditions in 2012

13. 0
1
2
3
4
5
6
Clones
Scale
Resistance to Late Blight based on Scale of susceptibility in 40 elite clones
over five seasons years in Oxapampa, 2009‐2013

14. Total tuber
yield tha‐1
under LB AUPDC
Female Male San Ramon La Molina Majes Oxapampa Oxapampa LB* PVX PVY Heat Drought
30 398098.203 393371.58 392639.31 21.29 41.83 11.48 24.03 199 0.75 ER T T
31 398098.204 393371.58 392639.31 16.81 29.98 16.65 24.93 94 0.47 ER T
32 398098.205 393371.58 392639.31 18.66 26.67 13.26 11.30 259 0.56 ER T
33 398098.231 393371.58 392639.31 20.37 21.37 13.28 21.85 18 0.19 ER T
51 398201.510 393242.5 392633.64 24.54 35.05 30.65 19.41 529 0.80 ER ER T
55 398208.219 393371.58 392633.64 24.26 34.26 27.93 14.85 607 2.15 ER ER T T
56 398208.29 393371.58 392633.64 26.85 44.57 31.69 11.48 905 2.53 ER ER T
58 398208.505 393371.58 392633.64 21.29 38.19 24.87 48.63 59 0.44 ER ER T
60 398208.670 393371.58 392633.64 25.37 36.58 18.46 32.52 59 0.48 ER ER T
36 398098.98 393371.58 392639.31 16.20 16.50 13.80 12.59 166 0.35 ER T
3 398017.53 391002.6 392639.31 26.50 36.70 19.20 15.37 488 0.93 ER T
62 Amarilis 11.94 25.00 11.33 13.37 1155 3.33 NT
63 Desiree 15.74 24.71 10.16 S T
64 Granola 11.02 13.09 2.48 S T
Yungay 3.15 2079 6.00 NT
Kory 9.41 488 1.79 NT
#
Total tuber yield tha‐1
High
Temperatures Resistance Tolerance Pedigree
Clone
Eleven clones with early tuberization (90 days), heat tolerance, resistance to late
blight and extreme resistance to PVY suitable for mid‐elevation tropics and climate
change

15. In summary good progress has been achieved in this population and
40 outstanding clones have been selected for their heat tolerance,
resistance to late blight and high tuber yields and 90 days from
planting to harvest.
In the screening for drought tolerance 10 clones were identified that
maintain their yields under water deficit conditions and that
showed higher values of drought tolerance index.
28 clones were stables and 12 were unstables but all with high tuber
yield and were selected as elite clones.
Conclusions

16. Eleven clones with resistance to late blight, heat tolerance, early
tuberization, and extreme resistance to PVY suitable for mid‐
elevation tropics and climate change; are available for variety
development and further use in breeding.
29 mid‐maturing clones with heat tolerant, late blight resistant
and early maturity but without extreme resistance to PVY can be
recommended for highland conditions.

17. Harvest San Ramon 2012

18. Thank you