Germination and ultrastructural studies of seeds produced by a fast-growing, drought-resistant tree: implications for its domestication and seed storage

Moringa oleifera, or miracle tree, is known in many parts of the world for its multiple uses as an agroforestry crop. However, seeds of this species lose their viability within 6 to 12 months of harvest, and thus finding appropriate storage conditions to ameliorate deterioration due to ageing is essential. In a new study published in AoB PLANTS, Fotouo et al. investigated the longevity of seed stored in the fruit (capsules). They found that the inner layers of the seed coat that remain attached to the cotyledons probably play a role in seed dormancy of Moringa oleifera. Cotyledons of seeds stored for one year showed no sign of deterioration. In some cells of the three-year-old cotyledons, the membranes of the protein bodies had deteriorated. Cell deterioration was also marked by the collapse of the cell wall adjacent to the intercellular cavity. The decrease in seed viability during storage was associated with the loss of membrane integrity as confirmed by an increase in electrolyte leakage.  The authors concluded that the longevity of Moringa oleifera seeds can be extended if they are stored within their fruits under favourable conditions.