Seed Longevity and Deterioration

Abstract The fundamental deteriorative processes that lead to loss of seed viability contrastingly vary between desiccation insensitive (orthodox) and sensitive seeds (recalcitrant). Orthodox which undergo maturation drying are bestowed with protective mechanisms guard the against deterioration. They include accumulation antioxidants, non-reducing sugars, proteins such as late embryogenesis abundant proteins, heat-shock lipocalins, hormones chemical protectants (raffinose family oligosaccharides, flavonoids, lignins, vitamin E). nuclear DNA is packed denser chlorophyll degraded. Besides, cytoplasm capable transitioning liquid glassy state depending on moisture content aiding in maintenance potential. In dry seeds, ensures stabilization cellular components by arresting cell metabolism. However, even low a cytoplasm, reactive oxygen species generated due presence storage atmosphere may cause ageing seed. As increases, mitochondrial respiration gets activated, also leading increased production species, owing inefficient activity. oxidation essential molecules DNA, RNA, lipids. Further, membranes get oxidized, reduced aerobic When damage not substantial, orthodox repairing molecular damages accumulate during storage, enabling partially overcome extend their longevity. This includes activation repair membranes, mitochondria imbibe water. Unlike recalcitrant largely devoid rapid shed from mother tree at high while they metabolically active. After dispersal, changes cytoskeleton (physical damage), besides species-induced lack antioxidant activity (metabolism-induced damage). Even when maintained under content, exhibit dysfunction organelles extensive vacuolization predisposing Thus, prone deterioration either or content.