8:30 am Breeding for Sustainable Production in a Changing Climate - Understanding the Physiological Basis of Genetic by
Environmental Interactions: Introduction
(01) Palta, J1, K. McCue2, S. Jayanty3, B.
aniels-Lake4, P. Vander Zaag5 and C. Yencho6. 1University of Wisconsin Madison
WI., 2ARS Albany, CA., 3Colorado State University, CO, 4Agriculture and Agi-Food Canada,
Kentville, NS, 5Sunrise Potato, ON, Canada, 6NC State University, Raleigh, NC.
Abiotic stresses (drought, cold, heat, excess water, salinity) result in losses in yield and quality of crops. In addition,
these stresses limit the areas that can be cultivated because of yield instability and crop loss. Global warming models
predict erratic weather patterns making the impact of these stresses more severe and unpredictable. Changes in climate are
also predicted to impact on the severity and incidences of plant diseases. Over the past 25 years, a lot of progress has been
made toward understanding the physiological mechanisms for injury and adaptation to these stresses. In addition a number of
genes linked to tolerance of plants to these environmental stresses have been identified. This symposium is aimed at bringing
together physiologists, breeders and molecular biologists to discuss strategies to prepare for sustainable production in a
changing climate scenario. Topics to be covered will include climate change models and impact on crop production, molecular
mechanisms of injury by and adaptation to abiotic stresses, germplasm and genetic resources in relation to abiotic stresses
and strategies to prepare for sustainable production in view of climate change.
8:40 am Challenges to Sustainable Potato Production in a Changing Climate: A Research Perspective.
(02) Quiroz, R., A. Posadas, C. YarlequŽ, H. Heidinger, C. Barreda, R. Raymundo,
M. Carbajal, H. Tonnang, J. Kroschel, G. Forbes, and S. De Haan. International Potato Center, Lima, Peru.
Potato production systems face constant changes in climate conditions and the projections for the future indicate that changes
in temperature and precipitation are expected in certain regions of the world. The impact will depend on what we do today to
avoid negative consequences. Climate projections might have mixed repercussions on crops. Some crops and areas will benefit
and some will be negatively impacted. These projections are difficult to implement in data scarce countries where surrogate
data must be constructed. The most likely temperature increases will not only have direct consequences on yield but are expected
to produce an outburst of pest and diseases with consequences on productivity, use of toxic chemicals, and incorporating natural
carbon sink locations into agriculture to guarantee food production. This might generate a vicious cycle that must be avoided.
The challenge is to generate and promote appropriate technologies, management practices and policies that might not only maintain
or increase yield but also reduce the dependency on incorporating more land into agriculture and the use of toxic chemicals that
affect the environment and people's health. The presentation will highlight some of the research the International Potato Center
is conducting in developing countries, mainly on the development of tools and methods to better assess the challenges to sustainable
potato production.
9:20 am Mining the Potato Germplasm to Prepare For Sustainable Production in a Global Climate Change Scenario.
(03) Ramsay, Gavin, Nithya Subramanian, Glenn Bryan, Christine Hackett, Gaynor McKenzie
and Philip White. The James Hutton Institute Invergowrie, Dundee, Scotland.
In its Andean homeland the potato is challenged by drought, heat and cold stresses and is adapted to a variety of edaphic environments.
The genetic variation available to breed potato for the current and future problems of sustainability can be expected to be greatest
in wild potato species which are exposed to the most extreme environments, high in Andean landraces, and lower in the Chilean landraces
which are adapted to a damp climate and which contributed greatly to the high yielding varieties grown across the world today. This
presentation will show how linkages can be made between different approaches to deliver new tools for breeding. The development and
potential of two types of population capturing Andean diversity in useful form will be described. These populations exhibit broad
variation for rooting traits, mineral uptake and redistribution and other tuber traits. For tuber mineral traits, an integrated
approach will be described which brings together multivariate analysis of tuber mineral levels in wild, landrace diversity populations
and modern potato with genetic analysis using both diversity and biparental genetic mapping populations. Progress on understanding
the mechanisms of mineral accumulation, and genetic analysis linking quantitative trait loci to potato genome locations and candidate
genes at these locations will be described. Finally, wild potato species may add additional traits not already present in cultivated
germplasm. The rooting profiles and tuberization strategies of a panel of wild species will be described to indicate their potential
to enhance further sustainability traits in cultivated potato. The prospects will be discussed for the use of knowledge gained from
the marriage of appropriate genetic resources with genomics.
10:00 am BREAK
10:30 am Preparing Potato for Climate Change: Breeding, Selection and Efficient Use of Genetic Resources for Abiotic Stress.
(04) Amoros, W.1, R. Cabello1, R. GutiŽrrez1, M. Kadian
2. C. Carli3, E. Salas1, S. Munive1 and M. Bonierbale1. International Potato
Center (CIP), Lima-Peru1; Delhi-India2; and Tashkent-Uzbekistan3.
Due to the implications that climate change will no doubt have on potato yields and production patterns, CIP's breeding program is
developing new generations of broad-based disease resistant populations better-adapted to drought and heat. More than 300 clones and
selected progenies were evaluated under water-limiting and high temperature conditions in the desertic coast of Peru and in India,
Bangladesh, Uzbekistan and Tajikistan. Elite clones with high yield indexes and superior progenitors of stress tolerance were
identified and information incorporated for collaborative breedign across environments. Meanwhile, in order to assess wider diversity
of cultivated potatoes, a set of 918 potato accessions including landraces, improved varieties and advanced breeding material has
been evaluated under full and limited irrigation conditions in Peru. Significant differences were found for tuber yield, tuber number
and tuber size among accessions and cultivar groups in both treatments. Early generation screening methods were developed to screen
new families for heat tolerance under in vitro conditions targeting ability to tuberize at 25¼C night and 19¼C day temperatures.
Physiological parameters and drought tolerance mechanisms have been studied in complementary approaches: Evaluation of water use
efficiency toward the identification of tolerance to dehydration revealed differences in transpiration efficiency and conductance;
and evaluation of survival under drought, permitted the identification of genotypes with high osmotic adjustment. The use of remote
perception tools such as infrared thermometer, reflectance, infrared camera, measuring NDVI indexes and canopy temperature, is
combined with germplasm evaluation and assist and accelerate screening and breeding for drought tolerance.
11:10 am Addressing the Impact of Temperature Stress on Potato Production: Merging Physiological and Genetic Approaches.
(05) Palta, J and J. Bamberg. University of Wisconsin, Madison WI.
Two general approaches can be undertaken to develop strategies for sustainable production in a changing climate. (i) Understand and
exploit the genetic and physiological variations that exist in the germplasm in relation to abiotic stresses. Studies should be
aimed at identifying physiological and genetic traits that are linked to abiotic stresses. This basic information could be used to
develop strategies for moving desirable traits to the cultivated potatoes. (ii) Develop production practices for mitigating the impact
of abiotic stresses. Before implementing these approaches we need to understand the physiological and genetic mechanisms. Specifically,
information is needed on mechanisms of injury and survival as well as on mechanisms of acclimation to abiotic stresses. We have made
significant progress on these mechanisms in potato. Using potato as a model crop, this presentation will illustrate how we may develop
strategies for sustainable production in a changing climate. We find that: (i) Genetic resources are available that can be deployed for
improving the performance of cultivated potatoes under temperature stresses. There is a significant genetic variations among potato
species for freezing and heat tolerance as well as for acclimation ability to temperature stresses. (ii) Cold and heat stresses impair
cell membrane functions that appear to be mediated by changes in cellular/membrane calcium and changes in membrane lipid composition.
Calcium can mitigate the response of potato plants to both heat and cold stresses; (iii) Precise screening for frost tolerance and
acclimation ability has allowed us to improve frost hardiness of cultivated potatoes. By combining physiological and genetic approach
we may address the issues related to climate change.
11:50 am Discussion
