Comparative analysis of salinity tolerance mechanisms in geographically diverse maize genotypes

Authors: Sandhu, Devinder; RAJANDEEP, SEKHON - Clemson University; Ferreira, Jorge

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 11/11/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Salinity is a major abiotic stress factor that limits agricultural productivity worldwide by affecting plant growth, ion balance, and genetic expression. This study aimed to provide a comprehensive evaluation of salinity tolerance in maize by assessing biomass yield, ion accumulation, and gene expression in 13 diverse maize genotypes under saline irrigation levels of 1.8 and 16 dS m'¹. Our results revealed significant variation in salt tolerance, with genotypes showing a strong correlation between shoot and root biomass production under high salinity. Genotypes with lower sodium (Na) and chloride (Cl) accumulation in leaves generally demonstrated better performance, indicating that reduced ion toxicity plays a key role in salt tolerance. Gene expression analysis in roots highlighted two major response types: some genotypes exhibited constitutive expression of salinity tolerance genes even under control conditions, while others displayed a time-dependent activation of these genes. These expression patterns suggest diverse salinity tolerance mechanisms among genotypes, involving Na+/Cl- efflux, vacuolar sequestration, root-to-shoot transport, and ion homeostasis. Our findings highlight the importance of assessing diverse genotypes and multiple traits to unravel the genetic networks regulating salinity tolerance, providing valuable insights for enhancing maize productivity in saline environments.