Dodder-transmitted mobile signals prime host plants for enhanced salt tolerance

Area of Science:

• Plant Biology
• Ecology
• Stress Physiology

Background:

• Dodders (Cuscuta spp.) are parasitic plants that can connect multiple hosts simultaneously.
• Salt stress is a significant abiotic challenge for plants.
• The transmission of stress-induced signals between plants via parasitic connections is not well understood.

Purpose of the Study:

• To investigate if dodder mediates the transmission of salt stress-induced systemic signals between connected hosts.
• To determine if these signals prime connected hosts, affecting their salt stress tolerance.
• To explore the physiological and transcriptomic changes induced by these inter-plant signals.

Main Methods:

• Simultaneous parasitism of multiple cucumber plants using dodder.
• Application of salt stress to one host plant.
• Assessment of physiological responses (leaf wilting, cell death, proline content, stomatal conductance, photosynthesis) in connected hosts.
• Transcriptomic analysis of connected cucumber plants.

Main Results:

• Salt treatment of one host primed connected hosts, reducing leaf wilting and cell death under subsequent salt stress.
• Transcriptomic profiles of connected hosts largely mirrored the salt-treated host.
• Inter-plant signaling induced physiological changes in connected hosts, including altered proline levels and photosynthetic rates.

Conclusions:

• Dodder acts as a conduit for salt-induced inter-plant signaling.
• These signals confer enhanced salt tolerance to connected hosts through physiological and transcriptomic adjustments.
• This study highlights the role of parasitic plants in mediating plant-plant interactions and stress responses.