Using gas chromatography and mass spectrometry (GC-MS) for the detection of drought stress effects on the metabolome of Solanum tuberosum varieties

Background: Potato (Solanum tuberosum L.) is among the highest-yielding staple crops worldwide, making its resilience to abiotic stress a critical factor in global food security. Yet, the potato yield is strongly dependent on many abiotic factors. Pressuring environmental matters like climate change urge to understand plant stress response to abiotic factors, such as drought. This knowledge will be essential in breeding more adaptable crop varieties to maintain food security. Previous studies showed changes in plant stress-related metabolites [1,2]. Methods: Ten potato varieties were tested for their drought stress response in a field trial. Four biological replicates of each variety were collected from both irrigated (control) and non-irrigated (treatment) fields 2024 in two time points in July (at the onset of flowering). Leaf discs were grinded, and their weight normalized to ~22 mg (freshweight). Primary metabolites were targeted in the analysis by collecting the polar phase of the Methanol-Chloroform-Water extract. The metabolites were quantified and identified using Gas chromatography-mass spectrometry analysis. Further processing was done using MS-Dial and statistical analysis with R. Results: Preliminary results indicate separation between the control and the treatment group. Between the potato varieties and treatment significant metabolite changes (e. g. in proline) with p-value < 0.05 could be measured. In total 39 primary metabolites (Sugar alcohols, amino acids and organic acids) were absolutely quantified and compared between the varieties. A correlation between the visual data (PolyPen RP 410 & ASD FieldSpec Handeld 2) obtained by AGES and a set of significantly changed metabolites was detected. Discussion: The differences could depend on varying conditions in the soil, the microclimate and pests in a field trial which were partially assessed and further analyzed by AGES. Conclusion: We were able to characterize metabolic changes in Solanum tuberosum that are likely related to the applied drought stress conditions.