Fungal Endophytes Are Associated with Improved Salinity Responses Across Quinoa Ecotypes

Area of Science:

• Plant Science
• Microbiology
• Agronomy

Background:

• Soil salinity severely limits global crop productivity.
• Enhancing plant stress tolerance is crucial for food security.

Purpose of the Study:

• To determine if root-associated fungal endophytes from salt-tolerant quinoa can improve stress responses in a salt-sensitive ecotype.
• To investigate the physiological and molecular mechanisms of stress mitigation.

Main Methods:

• Isolation and inoculation of fungal endophytes (Alternaria spp., Setophoma sp.) into salt-sensitive quinoa (BO75).
• Evaluation of physiological (photochemical efficiency, survival), biochemical (MDA, proline), molecular (gene expression), and elemental (ion distribution) parameters under severe salt stress (400 mM NaCl).

Main Results:

• Endophyte inoculation improved stress performance in the sensitive genotype, indicated by reduced oxidative damage (MDA), increased proline, and enhanced photochemical efficiency.
• Reduced expression of ion transporter genes (CqSOS1, CqNHX1) suggests improved ionic balance.
• Minimal effects were observed when endophytes were inoculated into the salt-tolerant genotype, indicating specificity.

Conclusions:

• Transferring fungal endophytes from halophytic ecotypes can significantly mitigate salt stress in sensitive crop genotypes.
• These endophytes hold potential for enhancing crop resilience and productivity in saline environments.