Integrated Approaches for Screening Salt Tolerance in Sugarcane: From in Vitro Selection to Field Evaluation

Salt is one of the biggest threats to sugarcane (Saccharum officinarum L.) farming globally because millions of acres of farmland have salt issues that affect their production of sugarcane. Sugarcane as a glycophyte (a plant that needs to grow in a freshwater environment) is at great risk from the ionic and osmotic stresses associated with salinity, which reduce the amount of sugar cane produced and inhibit the efficiency of photosynthesis. The solution to this serious problem is to develop a coordinated, multi-pronged research program that integrates controlled in vitro screening, characterization of salt-tolerant genotypes physiologically and biochemically, evaluation in the field, molecular omics, and artificial intelligence-based decision support systems. This review highlights recent advances in these areas. Salt-tolerant genotypes can be identified rapidly and in high-throughput form using in vitro selection of callus and shoot tip cultures, temporary immersion bioreactor systems, and polyethylene glycol-induced osmotic stress. Physiological and biochemical research has elucidated the major adaptive mechanisms of sugarcane, which include osmotic adjustment, activation of antioxidant enzyme activity (superoxide dismutase, catalase, and ascorbate peroxidase), ion homeostasis through the SOS pathway, and the accumulation of compatible solutes such as proline. Through multi-location field trial data evaluation (using the AMMI and GGE statistical models), stable high-yielding cultivars (such as CoG 7) that are tolerant to salt have been identified. Molecular omic studies that employ genomics, transcriptomics, proteomics, metabolomics, and GWAS data analyses along with genomic selection and the CRISPR/Cas9 genome editing technique are being used to improve the accuracy of developing salt-tolerant crops. Additionally, phenotyping and agricultural management in saline environments are changing due to Technology advancements, such as AI, Machine Learning, and Remote Sensing. Finally, the review identifies three primary translational gaps associated with Breeding Salt Tolerant Varieties (disconnect between In vitro tolerance and Field performance, no standard phenotyping protocol, and the complex polyploid Sugarcane Genome) and highlights Priority Areas for the development of Climate-resilient high-yielding Salt Tolerant Varieties.