Desiccation Tolerance as the Basis of Long-Term Seed Viability

摘要: Desiccation tolerance appeared as the key adaptation feature of photoautotrophic organisms for survival in terrestrial habitats. During further evolution, vascular plants developed complex anatomy structures and molecular mechanisms to maintain hydrated state cell environment sustain dehydration. However, role genes encoding behind this adaptive changed with their evolution. Thus, higher it is restricted protection spores, seeds pollen from dehydration, whereas mature vegetative stages became sensitive desiccation. maturation, orthodox lose up 95% water successfully enter dormancy. This allows maintaining viability even under strongly fluctuating environmental conditions. The desiccation are activated at late seed maturation stage associated accumulation embryogenesis abundant (LEA) proteins, small heat shock proteins (sHSP), non-reducing oligosaccharides, antioxidants different chemical nature. main regulators abscisic acid protein DOG1, which control network transcription factors, represented by LEC1, LEC2, FUS3, ABI3, ABI5, AGL67, PLATZ1, PLATZ2. complemented epigenetic regulation gene expression via methylation DNA, post-translational modifications histones chromatin remodeling. These fine regulatory allow during whole period germination radicle protrusion. time point, tolerance, critical process development.