Unveiling the secrets of lotus seed longevity: insights into adaptive strategies for extended storage

Abstract Seed longevity is crucial for long-term storage, but prolonged unfavorable conditions can lead to viability loss. This study integrated theoretical and experimental techniques to elucidate the inherent mechanisms underlying the unique ability of lotus seed capacity to maintain stable viability even after enduring years. Transcriptome analysis and microscopy revealed the sturdy structure of the lotus seed pericarp, which predominantly expressed cellulose synthase genes involved in cell wall biogenesis. The cotyledon serves as a nutrient source for seeds during long-term storage. Additionally, the inactivation of chlorophyll degradation pathways may allow for the retention of chlorophyll in the lotus seed plumule, potentially enhancing the environmental adaptability of lotus seedlings. While the reduced abundance of transcripts corresponding to heat shock protein genes could impact protein processing and consequently diminish the vitality of aging lotus seeds. Moreover, an expansion in the number of seed maturation and defense response genes was observed in the lotus genome compared to other 11 species, which might represent an adaptive strategy against long-term adverse storage conditions. Overall, these findings are crucial for understanding the mechanisms underlying lotus seed longevity and may inform future improvements in the extended storage periods of seed crops.