Molecular Mechanisms of Plant Responses to Abiotic Stress: Salinity and Heavy Metals

Abstract

Abiotic stresses are among the major environmental factors limiting plant growth and productivity, including salinity, heavy metal accumulation, drought, and temperature extremes. These stress conditions disrupt cellular homeostasis by affecting ion balance, osmotic regulation, metabolic processes, and gene expression, thereby negatively influencing plant development. Therefore, understanding plant responses to abiotic stress at the molecular level is essential for improving stress tolerance and ensuring sustainable agricultural production. Molecular approaches, particularly gene expression analyses, are effective tools for identifying defense mechanisms and adaptation processes activated under stress conditions. In this review, recent and well-recognized studies on abiotic stress conditions were reviewed, and the key molecular mechanisms and approaches involved in these processes were systematically evaluated. Molecular responses are observed to vary depending on plant species differences and the type and dose of salinity and heavy metal stress and are shaped according to specific stress conditions. This study highlights the importance of molecular responses to abiotic stress and emphasizes that understanding these mechanisms is crucial for developing stress-tolerant plant varieties and supporting sustainable agricultural practices.