Figure 1.

Epigenetic changes in plants under stress. Plants withstand various environmental stresses throughout their developmental stages and to overcome these challenges, epigenetic modifications play a vital role. These include covalent modifications of histone tails (acetylation, methylation, phosphorylation, ubiquitination, and the small RNA machinery). Epigenetic changes are the heritable phenotypic variations that are not always due to specific DNA sequence alterations, but the epigenetic regulation that involves certain chemical modifications at the molecular level which can alter the gene expression. DNA and chromatin modifications at the epigenomic level affect gene expression and play a prominent role in unveiling phenotypic responses against external stimuli. Epigenetic changes are reversible and heritable to control gene expression without any change in the DNA sequence. Epigenetics holds immense potential in crop improvement strategies, climate-smart breeding and stress resistance by choosing the favorable epigenetic states, formulation of novel epialleles, and regulation of transgene expression.