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The longevity of seeds stored in Genebank is based on their storability. However, the mechanism of seed storability is largely unknown. In previous studies, accelerated ageing treatments were always applied for rapidly acquiring different seed viabilities, which could not reflect the actual situation during seed storage, especially for the seed stored in Genebank. In this study, two wheat genotypes (accession TRI_23248 and TRI_10230) were supplied by IPK-Gatersleben Genebank, Germany, where they were stored for 10 years in the long-term storage (-18 °C) and at ambient conditions (20 °C) The comparison of viability of those seed after this storage period, identified TRI_23248 as storage tolerant (ST) and TRI_10230 as storage sensitive (SS). The abundance patterns of proteins in these seeds identified 93 protein spots in the ST and 105 spots in the SS seeds that were markedly changed; their functions were mainly associated with disease or defense, protein destination and storage, energy, and other. The ST seeds possessed a stronger ability in activating the defense system against oxidative damage, utilizing storage proteins for germination, and maintaining energy metabolism for ATP supply. These results provided novel insights into the mechanism of seed storability, which can facilitate the comprehensive understanding of seed longevity., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Reactive oxygen species are the main contributors to seed deterioration. In order to study scavenging systems for reactive oxygen species in aged seed, we performed analyses using western blotting, real-time quantitative reverse-transcription polymerase chain reaction, high-performance liquid chromatography, and antioxidant enzyme activity analyses in artificially aged rice seeds (Oryza sativa L. cv. wanhua no.11). Aging seeds by storing them at 50 °C for 1, 9, or 17 months increased the superoxide radical and hydrogen peroxide levels and reduced the germination percentage from 99% to 92%, 55%, and 2%, respectively. The activity levels of superoxide dismutase (SOD), glutathione reductase (GR), and dehydroascorbate reductase (DHAR) did not change in aged seeds. In contrast, the activity levels of catalase (CAT), ascorbate peroxidase (APX), and monodehydroascorbate reductase (MDHAR) were significantly decreased in aged seeds, as were the expression of catalase and cytosolic ascorbate peroxidase protein. Transcript accumulation analysis showed that specific expression patterns were complex for each of the antioxidant enzyme types in the rice embryos. Overall, the expression of most genes was down-regulated, along with their protein expression. In addition, the reduction in the amount of ascorbate and glutathione was associated with the reduction in scavenging enzymes activity in aged rice embryos. Our data suggest that the depression of the antioxidant system, especially the reduction in the expression of CAT1, APX1 and MDHAR1, may be responsible for the accumulation of reactive oxygen species in artificially aged seed embryos, leading to a loss of seed vigor., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)