Plant's Secret Life: Biochemistry behind the Stress Memory

Abstract

Plants, as sessile organisms, face various daily stressors that impact their growth, metabolism, and yield. In crop plants, understanding their responses to stressors and the transgenerational effects is crucial. We examined chickpea, tomato, and the model plant Arabidopsis to evaluate stress memory, its transfer to progeny, and resulting biochemical changes under optimal and stress conditions. In Arabidopsis, we found that memory responses and biochemical changes correlate with stress severity, with more severe stress prompting memory reset. In tomato, both moderate and severe stress had transgenerational effects, altering hormone and polyamine levels, and metal uptake dynamics. Notably, the F1 and F2 generations retained altered polyamine profiles, such as elevated cadaverine and putrescine levels, indicating a persistent transgenerational response. Furthermore, we explored how priming crops can leverage these biochemical changes for enhanced tolerance. Arabidopsis F2 seeds tested under different stressors showed that previous exposure to hexavalent chromium (Cr) induced increased tolerance to salt and cadmium (Cd) stress, attributed to elevated antioxidant enzyme activity and proline content. Plant memory is a complex process, and evidence of transgenerational memory transfer is still emerging. Our studies demonstrate memory effects up to the F2 generation, providing proof of transgenerational memory and associated biochemical profile alterations.