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Under the in luence of abiotic and biotic stress factors, gene expression can be altered with or without the involvement of stress hormones (a); changes in gene transcription may be made (b); stress factors can directly af fect chromatin by methylation of DNA, modi ication of histones terminal parts and in luence the condensation and recondensation of chromatin (c). These changes are largely reversible, but can alter the metabol ic or morphological characteristics of plants under stress conditions. These processes can contribute substantially to variations in plant growth, in luencing morphology and plasticit y, especially under stress conditions. Usually, new phenotypes are not transmit ted to t he offspring, although t he uniformit y of the characteristics of the new combinations of epigenetic diversity is observed. The epigenetic inheritance which presupposes the transmission of information f rom one generation of an organism to the next that affect s the traits of offspring without alteration of the primary structure of DNA is very rare. In most researches on epigenetic hereditary phenomena it is not excluded the involvement of genetic mechanisms (such as quantit ative traits, segregation distortion, and cytoplasmic inheritance) or effects that requir e the ongoing presence of the stimulus that can lead to non-Mendelian pat terns of inheritance. Actually, the term epigenetic heredity is often include the transmission of the acquired in ontogenesis information not only through mitosis, but also to the next generation through meiosis.