Trehalose: a multifunctional sugar and its metabolites are biotechnological targets for crop salinity tolerance under saline conditions

Abstract

Salinity stress is an abiotic threat that impairs crop growth, development, and productivity, placing a heavy burden on global agriculture. Understanding how crops tolerate salinity enables the development of biotechnological strategies to enhance crop resilience and yield, thereby securing sustainable food supplies for the growing global population. Trehalose, its metabolite trehalose-6-phosphate (T6P), along with key biosynthetic enzymes (trehalose-6-phosphate synthase, TPS; trehalose-6-phosphate phosphatase, TPP), have garnered increasing attention for their ability to enhance crop tolerance to salinity by modulating physiological, biochemical, and signaling processes. Therefore, strategies to increase trehalose levels or to enhance its metabolic functions are promising for researchers seeking to improve crop tolerance and yield in saline environments. This review explores the structure of trehalose, its biosynthesis, protective molecular mechanisms, and the vital functions of its metabolites in enhancing crop tolerance and productivity in saline soils. It also underscores biotechnological strategies targeting trehalose metabolism to enhance salinity resilience of crops, while critically evaluating current limitations and knowledge gaps. Further targeted manipulation of trehalose metabolism, tissue-specific regulations, and validating results in field-grown crops are also required to translate laboratory findings into agricultural applications.