Floods are the second gravest disaster for agriculture, causing crop losses and jeopardizing food security. Plants respond and cope with flooding events through a series of metabolic, physiological and developmental changes, many of which depend on the plant hormone ethylene. In addition, the transport of its immediate precursor 1-aminocyclopropane-1-carboxylic acid (ACC) appears to play an important role in flooding responses. Recent studies also suggest that ACC, or one of its elusive conjugates or derivatives, could take part in stress responses independently of ethylene. How waterlogging responses are coordinated by ethylene, ACC, or their interplay, between different tissues and cell types remains poorly understood. In this project, we envisage to shed light onto the spatial and temporal dynamics of ACC and ethylene metabolism in early responses to root waterlogging. To that end, the waterlogging response will be investigated in a single cell manner at three levels: transcript, protein and metabolite level. Using groundbreaking technologies, including single nucleus RNA sequencing and mass spectrometry imaging, this research will potentially spark a paradigm shift in understanding ethylene responses upon waterlogging.