Seed longevity is a complex process of key ecological and agronomic importance. DNA damage is a significant factor affecting seed ageing. Likewise, epigenetic changes can control gene expression and, therefore, seed response to ageing. The aim of the present work was to investigate the effect of ageing on nucleic acid stability and to identify reliable molecular markers that might help to monitor epigenetic changes within plant genetic resources during conservation. DNA profiles, evaluated by RAPD (random amplified polymorphic DNA), and methylation patterns, obtained by MSAP (methylation-sensitive amplification polymorphism), were compared in non-aged and aged Mentha aquatica seeds and plants produced by them. Germination decreased to 50% by storing seeds at 35°C and 12% wc for 28 days. RAPD profiles were 99% similar in these aged seeds compared to non-aged seeds. However, seedlings produced from the aged seeds showed a 13% dissimilarity compared to seedlings produced from the non-aged seeds. About 8% difference in the MSAP epigenetic profile was detected in seeds after storage and 16% difference was detected in the seedlings produced from them. This indicates that stress from high temperature and humidity during storage induced changes on the methylation state of seeds, and that changes were also detectable in the regenerated plants. Our results suggest that DNA integrity was compromised in seeds during ageing, and on seedlings produced by aged seeds. Genotype screening techniques such as RAPD and MSAP have the potential as markers of nucleic acid stability during seed ageing.

中文翻译：

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老化种子和再生植物中的 DNA 甲基化和完整性

种子寿命是一个具有关键生态和农艺重要性的复杂过程。DNA损伤是影响种子老化的重要因素。同样，表观遗传变化可以控制基因表达，从而控制种子对衰老的反应。本工作的目的是研究老化对核酸稳定性的影响，并确定可能有助于监测植物遗传资源在保护过程中的表观遗传变化的可靠分子标记。通过 RAPD（随机扩增多态性 DNA）评估的 DNA 图谱和通过 MSAP（甲基化敏感扩增多态性）获得的甲基化模式，在非老化和老化中进行了比较水生薄荷他们生产的种子和植物。通过将种子在 35°C 和 12% wc 下储存 28 天，发芽率降低到 50%。与未老化的种子相比，这些老化种子的 RAPD 谱有 99% 的相似性。然而，与由未老化种子生产的幼苗相比，由老化种子生产的幼苗显示出 13% 的差异。在储存后的种子中检测到 MSAP 表观遗传图谱的差异约为 8%，在从它们产生的幼苗中检测到 16% 的差异。这表明贮藏期间高温和高湿的胁迫引起了种子甲基化状态的变化，并且在再生植物中也可以检测到这种变化。我们的研究结果表明，老化过程中种子和老化种子产生的幼苗的 DNA 完整性受到损害。