The Opposite Roles of White Light in Regulating Germination of Fresh and Aged Seed in Tobacco

Light is one of the important environmental factors for seeds to evaluate whether the natural environment is appropriate for germination and subsequent seedlings emergence. The mechanism of light-mediated germination is mainly concerned with fresh seeds (FS) of model plants but is poorly understood in aged seeds. Here, the effects of light on germination of FS and naturally aged seeds (NAS) in tobacco and their relationship with plant hormones gibberellins (GA) and abscisic acid (ABA) were investigated. The results demonstrated that light promoted and inhibited the germination of FS and NAS, respectively. GA and ABA were involved in the germination control of NAS, as well as in FS. However, light suppressed GA signal and stimulated ABA signal in NAS, whereas it stimulated GA signal and suppressed ABA signal in FS. In addition, light stimulated the GA accumulation and reduction in ABA in FS while inhibiting the increase in GA level in NAS. Together, the present study demonstrates that light has opposite effects on the germination of FS and NAS, which are closely related to the metabolism and/or signaling of plant hormones ABA and GA.

Priming Fresh and Aged Seed of Soybean (Glycine max L.)

Background: High and stable production requires quality seed. Seed quality is the basis of efficient crop production and farmers need such seeds for optimum yield production. Therefore, various procedures are applied in seed production technology that aim to improve not only the germination of seeds but also the speed of its germination. These methods can reduce of seed aging and the effects of different agroecological factors. Methods: For research the impact of priming used seed aged seven months (fresh seeds) and seed was nineteen months old (aged seed). The seed was treated with following solutions: potassium nitrate (1%), ascorbic acid (100mgl-1) and potassium chloride (1%) for 6 hours and then germinated at 25°C in 8 days. Result: The analysis showed that seed aging resulted in a decrease in its germination energy and germination. Moreover, time required for germination is prolonged, the lipid peroxidation intensity and content of free proline are increased and the amount of vitamin C is reduced. The results showed that the effect of priming is dependable on variety selection, seed age and treatments. Therefore, we can conclude that there is no universal use of one only primer, as it may not be suitable for each particular cultivar and can ultimately lead to a decrease in the germination energy and germination.

A simple new method for aged seed utilization based on melatonin-mediated germination and antioxidant nutrient production

Seed deterioration, coupled with a decrease in nutrients, is unavoidable following long-term storage, and these seeds are therefore used as livestock fodder. Here, we developed a simple, rapid and efficient method of producing high amounts of antioxidants from deteriorated seeds via melatonin-induced germination. Legume seeds were subjected to high humidity at 55 °C for 12–36 h to obtain aged seeds with a 40% germination rate and severely reduced antioxidant nutrition (total phenolics content, ferric reducing power and 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging capacity). Aged seeds were then treated with 0.1 mM melatonin, resulting in the production of sprouts with a higher total phenolics content (fivefold), greater ferric reducing power (sevenfold) and greater DPPH radical scavenging capacity (twofold) compared to the aged seeds. These findings suggest that melatonin treatment efficiently converted aged seed reserve residues into antioxidant nutrients, providing an alternative use for deteriorated seeds in food production.

Comparative analysis of the Accelerated Aged seed transcriptome profiles of maize CSSLs (I178 and X178)

Seed longevity is one of the most essential characters of seed quality. Two Chromosome segment substitution lines (CSSL) I178 and X178 with significant difference on seed longevity were subjected to transcriptome sequencing before (0d-AA) and after five days of accelerated ageing (5d-AA) treatments. Compared to the non-accelerated ageing treatment (0d-AA), 286 and 220 differential expressed genes (DEGs) were identified in I178 and X178, respectively Among those, 98 DEGs were detected in both I178 and X178 after 5d-AA, Enriched GO terms included cellular components of cell part, intracellular part, organelle and membrane etc., including carbohydrate derivative catabolic process, carbohydrate synthesis, sugar isomerase (SIS) family protein etc. Transcriptome analysis of I178 and X178 showed that Alternative splicing (AS) occurs in 63.6% of the expressed genes in all samples. Only 381 genes specifically occurred AS in I178 and X178 after 5d-AA, mostly enriched in nucleotide and nucleoside binding. Combined with the reported QTL mapping result, the DEG and the AS information, 13 DEGs in the mapping intervals and 7 AS-DEGs were potential candidates may directly or indirectly associated to seed ageing.