Genome-Wide Dissection of Salt Tolerance Mechanisms in Maize

Soil salinisation poses a mounting threat to maize production worldwide, impairing growth through ionic imbalance, osmotic stress and oxidative damage. Dissecting the genetic basis of salt tolerance has advanced from single‐gene studies to genome‐scale approaches that combine high‐density markers with phenotyping under saline conditions. Genome‐wide association studies (GWAS), quantitative trait locus (QTL) mapping, bulked segregant analysis (BSA) and transcriptome sequencing have revealed numerous loci and candidate genes governing ion transport, osmotic adjustment, stress signalling and root architecture. Key players include Na+/H+ antiporters, Cl– transporters and transcription factors from WRKY, NAC and bHLH families. Integrative analyses of coding and non-coding RNAs have begun to chart regulatory networks, while gene‐editing tools validate functions and enable precise breeding. The collective insights underpin marker-assisted selection and genomic prediction for salt-tolerant maize varieties adapted to marginal lands.

Research from Nature Portfolio

A foundational study demonstrated that phosphate nutrition modulates maize salt tolerance by enhancing Na+ exclusion from leaves. Application of elevated phosphate led to increased expression of ZmNHX1 and phosphate transporter genes ZmPHT1;8 and ZmPHT1;9, promoting Na+ efflux and K+ retention in roots. Enhanced root proliferation and shoot growth accompanied reductions in reactive oxygen species under saline treatment. These findings illuminate the interplay between nutrient uptake and ion homeostasis and establish a nutritional route to improve salt resilience in maize.

Genome-Wide Dissection of Salt Tolerance Mechanisms in Maize publication trend

The graph below shows the total number of articles in genome-wide dissection of salt tolerance mechanisms in maize across all publications each year (not limited to Nature Index journals).

Technical terms

Genome-wide association study (GWAS): An analysis that scans the entire genome for statistical associations between genetic variants (often SNPs) and phenotypic traits.

Quantitative trait locus (QTL): A genomic region that contributes to variation in a quantitative trait, such as salt tolerance, often identified by linkage or association mapping.

Single-nucleotide polymorphism (SNP): A single base-pair variation in the DNA sequence among individuals, frequently used as a genetic marker in association studies.

Transcriptome sequencing: High-throughput determination of all RNA transcripts present in a tissue, enabling identification of differentially expressed genes under stress.

Differentially expressed gene (DEG): A gene whose expression level changes significantly in response to a treatment or condition, such as salt stress.

References

1. Impacts of salinity stress on crop plants: improving salt tolerance through genetic and molecular dissection. Frontiers in Plant Science (2023).
2. Exogenous Pi supplementation improved the salt tolerance of maize (Zea mays L.) by promoting Na+ exclusion. Scientific Reports (2018).
3. Natural variation in ZmNAC087 contributes to total root length regulation in maize seedlings under salt stress. BMC Plant Biology (2023).
4. Molecular dissection of maize seedling salt tolerance using a genome‐wide association analysis method. Plant Biotechnology Journal (2021).
5. A Combination of a Genome-Wide Association Study and a Transcriptome Analysis Reveals circRNAs as New Regulators Involved in the Response to Salt Stress in Maize. International Journal of Molecular Sciences (2022).