Cakile maritima model halophyte platform for saline soil phytoremediation

Overview

Soil salinization destroys roughly 25 million acres of arable land each year, reducing productive capacity and driving environmentally destructive expansion into new land. Halophytes—plants naturally adapted to salty environments—offer a biological route to reclaim saline soils through phytoremediation, but progress has been limited by the absence of a well-characterized model species with rich genomic resources. This project develops Cakile maritima, a member of the Mustard family, into a model halophyte and a foundation for breeding salt-tolerant crops that restore degraded farmland.

Technical specifications

C. maritima is uniquely positioned among halophytes because it exhibits all three independently evolved salt-regulation strategies—exclusion, excretion, and accumulation—providing a single system in which the full spectrum of salinity tolerance mechanisms can be studied and compared. Key features include:

• Close phylogenetic relationship to Arabidopsis thaliana and Brassica mustard crops, simplifying gene annotation and translating findings directly to related crops
• Short life cycle of approximately three months, enabling rapid experimental turnover
• Relatively small genome, reducing sequencing and assembly complexity
• Chromosome-scale genome assembly using PacBio HiFi reads and Hi-C chromatin conformation capture
• Annotation using existing RNA-seq data combined with gene models from A. thaliana and Brassica
• Comparative genomics pipeline to construct gene families, build a coalescent species tree, and identify genes under positive selection along with gene family expansions and contractions
• Differential expression analysis of C. maritima under saline versus non-saline conditions to refine candidate gene lists
• Translational outputs including targets for genomic selection and gene editing to develop crops suited for soil reclamation

Technology readiness level

The project is at an early research stage, focused on generating foundational genomic resources and candidate gene inventories. Prior physiological studies on C. maritima and published evidence that halophyte-based phytoremediation performs comparably to chemical remediation support the scientific premise, but comprehensive genomic characterization and breeding-ready targets have not yet been produced. Current efforts are directed at genome assembly, annotation, comparative analysis, and expression profiling to build the knowledge base required for downstream crop development and field validation.