On the path to stress-tolerant potatoes

How do different potatoes respond to heat, drought, and waterlogging stresses? EU-backed scientists are investigating the changes that make potatoes resilient or susceptible.

Whether we prefer them steamed, boiled, fried, roasted or baked, it is hard to imagine a modern-day diet without potatoes. A good source of fibre and full of antioxidants, the potato is one of the most important food crops in the world – a crop that climate change is taking its toll on.

The potato’s vulnerability to climate-induced environmental stresses such as extreme temperatures, flooding and droughts is raising major concerns about food security. To help address these concerns, the EU-funded ADAPT project is developing new strategies to ensure increased potato crop productivity, yield stability and quality in the challenging growth conditions of the future.

One of ADAPT’s objectives is to identify the morphological, physiological and molecular changes that make different potato cultivars resilient or not to single stresses (e.g. heat, drought, flooding) and relevant combinations of these stresses. To this end, plant scientists, farmers and potato breeders participating in the ADAPT project selected 30 potato cultivars to study in controlled greenhouse experiments.

Stress conditions and sampling points

As reported ADAPT's project partner European Potato Trade Association, Belgium, the project’s exploratory phase entailed determining the stress conditions and most informative sampling points. These two factors were initially investigated in a pilot experiment carried out at the plant phenotyping platform of another project partner, Photon Systems Instruments, located in Czechia.

There, the potato cultivar Desirée was exposed to heat, drought, and waterlogging stresses (single or combined), and plant responses were analysed daily through High-throughput phenotyping (HTP) technologies.
 

The findings from this initial investigation will be used in the second part of the exploratory phase. This involves the use of optimized set-ups and stress conditions to establish the genetic differences determining heat, drought and waterlogging responses in potatoes.

The ultimate goal is to identify tolerant and susceptible cultivars and elucidate the bases of these differences at the molecular and physiological levels. Greenhouse experiments to determine selected potato cultivar responses to heat, drought and waterlogging stresses were also conducted in 2021 at ADAPT project partners Friedrich-Alexander-Universität (Germany), Wageningen University & Research and Utrecht University (the Netherlands), respectively.

The experiments revealed genetic differences in stress responses, particularly in agronomic traits such as harvest index and tuber yield, the news item reports.

In addition to potato cultivars with single-stress tolerance or susceptibility, the researchers also identified cultivars that were tolerant or susceptible to multiple stresses, "inspiring the entire ADAPT consortium to investigate this phenomenon."

The ADAPT (Accelerated Development of multiple-stress tolerant Potato) researchers’ plan for 2022 is to conduct deep phenotyping of three tolerant and three susceptible cultivars, and to verify the phenotypic responses with gene expression analyses.