DNA Methylation Changes Reflect Aluminum Stress in Triticale and Epigenetic Control of the Trait

Aluminum (Al) stress is typical for acidic soils and may affect cereals' yield. Al tolerance in triticale is mostly affected by the aluminum-activated malate transporter (ALMT) gene (7R) and some other QTLs (3R, 5R, and 6R). The trait is heritable in about 36% of cases, indicating that epigenetic factors may impact the phenomenon. This study demonstrates that utilizing different methods to quantify DNA methylation changes induced by Al stress results in detail differences, and the results evaluated should be compared critically. The Common and the basic General approaches are sufficient if general information is needed. The General (extended variant) approach may deliver data on methylation changes affecting symmetric sequence contexts. The markers assigned to DN-CG, DM-CG, and DN-CHG were suggested as the most important in explaining Al tolerance in triticale. Analysis of the maps constructed based on root tips and leaf tissues showed different densities of the epigenetic markers but reflected the comparable patterns of their distribution, supporting the hypothesis that Al stress could be transmitted to other plant tissues due to somatic memory. Methylation changes occur throughout the genome and are not associated with specific genes related to aluminum stress.