Harnessing light, defying salt: How photobiomodulation unlocks Maize's hidden potential

Area of Science:

• Plant Science and Agronomy
• Biophysics and Laser Technology

Background:

• Salinity is a major abiotic stress limiting crop productivity due to soil salt accumulation.
• Laser bio-stimulation is explored for enhancing plant growth and stress tolerance by influencing cellular processes.
• Understanding the mechanisms of laser priming for salt stress resilience in crops like maize is crucial.

Purpose of the Study:

• To investigate the impact of laser priming parameters on maize (Zea mays L.) seed development and salt stress adaptation.
• To determine optimal laser irradiation parameters for enhancing germination and mitigating salinity damage.
• To elucidate the morphological, physiological, and biochemical responses of laser-primed maize seeds to salinity.

Main Methods:

• Maize seeds were primed using varying laser irradiation doses (0.3–3.0 J/cm²) at 660 nm wavelength.
• Evaluated germination efficiency, seedling vigor index (SVI), and salt stress mitigation.
• Conducted scanning electron microscopy (SEM), contact-angle (CA) measurements, thermal analysis, and biochemical assays.

Main Results:

• A laser dose of 0.73 J/cm² significantly improved radicle length, plumule height, and SVI.
• Lower doses (0.29 and 0.48 J/cm²) enhanced salinity resilience in salt-stressed seedlings.
• Laser treatments did not alter seed coat morphology or hydrophilicity but induced specific biochemical responses linked to salt tolerance.

Conclusions:

• Laser priming effectively stimulates adaptive physiological pathways in maize seeds, enhancing salt tolerance.
• Specific laser dosages elicit distinct responses, suggesting tailored applications for germination and stress resilience.
• Laser priming offers a promising, non-invasive method to improve crop performance under saline conditions.