Mineral nutrient acquisition under abiotic stress conditions

Mineral nutrient acquisition is central to plant growth, productivity and resilience, particularly under abiotic stresses such as drought, salinity, alkalinity, waterlogging, extreme temperatures, acidity and metal toxicity. Among essential mineral nutrients, nitrogen (N), phosphorus (P), potassium (K) and micronutrients such as zinc (Zn) and iron (Fe) are most severely affected under stress conditions, with nutrient uptake reductions often ranging from 20–60 % depending on stress intensity and crop species. These environmental stresses interfere with nutrient availability, transport and assimilation by modifying root morphology, membrane transport activity and gene expression patterns. This review summarises existing knowledge on the response of plants to such challenges, including physiological adjustments, transcriptional regulation of nutrient transporters, hormonal signalling and symbiotic interactions. Special attention is given to the roles of aquaporins, ion channels and nutrient-specific transporters, including nitrate transporters (NRTs), phosphate transporters (PHTs), high-affinity potassium transporters (HKTs) and zinc/iron transporters (ZIP) family members, in maintaining nutrient homeostasis. Recent studies indicate that improved regulation of these transport systems can enhance nutrient use efficiency by 15–40 % under adverse environments. The review also examines emerging approaches involving microbial biostimulants, including plant growth-promoting rhizobacteria and fungal bioinoculants, as well as chemical elicitors such as salicylic acid, that enhance nutrient uptake under stress conditions. Insights into these integrated responses provide avenues for improving nutrient use efficiency and strengthening crop resilience in marginal environments.