PubMed · 2026-06-26
Researchers identified how cucumbers survive flooding by growing emergency roots from their stems. Waterlogging triggers ethylene, which activates a transcription factor that rewires abscisic acid signaling — normally a drought-stress circuit — to instead fuel root growth and keep the plant alive.
CRISPR knockout of CsWRKY41 significantly impaired adventitious root formation in flooded cucumbers, while overexpression enhanced it — confirming it as a master regulator of flood survival.
CsWRKY41 acts as both an activator and a repressor within the same pathway, switching on the ABA receptor CsPYL4 while simultaneously silencing the phosphatase CsPP2C24 to tip the hormonal balance toward root growth.
Overexpression of the ABA receptor CsPYL4 upregulated the peroxidase gene CsPrx2 and increased hydrogen peroxide accumulation inside the hypocotyl, directly promoting new root development.
