Wild Tomatoes More Stress-Tolerant

In an international collaborative large-scale project, researchers from RWTH Aachen and the Max Planck Institute of Molecular Plant Physiology, Golm, succesfully deciphered the genome of the wild tomatoe species Solanum pennellii. The research results of the project, which provide the basis for future tomato breeds, have now been published in the international high-profile journal “Nature Genetics.”

 

In the intense breeding and domestication processes, Solanum pennellii’s resistance against pests, diseases and droughts have been lost. Wild variants, by contrast, have greater genetic variety and thus are of interest to researchers seeking to optimize the resilience and ingredients of tomatoes and other crops, such as potatoes.

Solanum pennellii is native to very the dry slopes and sandy regions in the Andes in South America; the variety is highly stress-resistant against droughts and pests. By interbreeding with domestic tomatoes researchers already succeeded in improving traits such as yield, chemical composition, and stress tolerance. However, so far, there was insufficient knowledge of the genes responsible for these agricultural traits.

The consortium of research teams from international universities and research institutions was led by Björn Usadel from RWTH Aachen and Alisdair Fernie of the Max Planck Institute of Molecular Plant Physiology. In collaboration with Forschungszentrum Jülich, Usadel’s research group provided the material which formed the basis for the sequencing process. Furthermore, the bioinformatics researchers were responsible for decoding the DNA sequence and the gene prediction process.

As Professor Usadel explains, “With the help of statistical analysis were were able to identify transposons, so-called jumping genes. We assume that they play a role for the stress tolerance of the wild tomato variety. Comparative analyses of the genetic makeup of the wild and domestic tomato varieties hint at a more complex secondary metabolism of Solanum pennellii and provided us with insights into the wild variety’s adaptive mechanisms against various stress factors.”

Knowledge of the genome sequence will help to identify associations between traits and genes. The deciphered sequences provide insights into the adaptive mechanisms to various environmental conditions and the development of stress tolerance. As Professor Usadel concludes, “With the help of the newly-gained genetic information it becomes possible to describe the molecular bases for certain traits faster and more precisely. This forms the basis for faster and more efficient breeding processes to improve our agricultural plants and thus our most important food sources.”