The Role of Ionomics as Functional Genomics of Elements in Plant Abiotic Stress Tolerance

In recent decades, various phenomena have taken place in the world around us that have greatly overshadowed human life. From the mid-20th century to the present, severe climate change, including global warming, has become a worldwide challenge. Global warming affects plants through abiotic stresses leading to decreased food production. Meanwhile, according to estimates, the world’s population is expected to reach 10 billion by 2050. To meet the upcoming global food demand under a rapidly changing climate, there is an urgent need to develop multi-stress tolerant plants to increase or sustain productivity. Hence, it is crucial to understand the basic response of plants to abiotic stress, especially at the molecular level. Such a level of detailed information about the complex molecular mechanism of stress tolerance in plants can be uncovered by OMICs tools. Among OMICs approaches, an emerging field called “ionomics” has been employed for investigating abiotic stress tolerance in plants. Ionomics focuses on the analysis of the “ionome,” standing for the mineral nutrient and trace element compositions of an organism, including both essential and non-essential elements, metals, and nonmetals. The aim of ionomics is to quantitative measurement of the elemental profile of an organism for understanding the mechanism of changing the inorganic composition of organs, tissues, cell types, and single cells of target organisms by varied external stimuli, including abiotic stress. The exposed plants to any condition of abiotic stress may affect the status of the elements as a consequence of alterations in genetic or physiological levels. The elements play a crucial role as cofactors of enzymes involved in regulatory pathways and subsequently in maintaining cell integrity. As a result, the alteration of the plant element profile can alter the metabolic pathways dramatically. Thus, the study of ionome through the ionomics approach provides a practical framework for breeders to achieve a better understanding of various biological pathways involved in elements regulating along with the changes in their concentration in plants. This ability makes ionomics an excellent approach to uncovering the mechanism of plant responses to harsh environmental conditions such as abiotic stress at the molecular level.