Seeds, Volume 1, Issue 3 (September 2022) – 5 articles

The knowledge of the physiological aspects of Caatinga’s vegetal species is extremely important for preserving this biome, which suffers with human impacts, mainly to select propagation methods. Erythrina velutina is a Brazilian tree, generally found in Caatinga, with medical and forestry potential. The objective of this paper was to determine the best soaking period in gibberellin solution to achieve the highest germination and to evaluate the internal anatomy by digital microtomography of E. velutina seeds. The design was completely randomized and consisted of eight treatments: 1, 3, 6, 12, 24 and 48 h of soaking, scarified seeds and the control with no-scarified seeds. Digital microtomography was efficient in describing the anatomy of the seeds and distinguishing their tissues. There was no significant difference between the treatments at different soaking times, as the gibberellic acid did not influence the germination; only the control presented a lower germination percentage, differing from the other treatments. The study presents evidence that E. velutina seeds do not require the exogenous use of gibberellic acid, but only the scarification process. In addition, the use of digital microtomography can be useful in understanding the anatomy of seeds, especially forest species, which can contribute to the future studies of other plant species. Full article

This work aimed to study the osmotic-dehydration kinetics of pomegranate seeds (PSs) (Punica granatum L.) using three fruit (apple, bitter orange and grape) juice concentrates as osmotic solutions (OSs) (ratio (1/4) m/v, 55° Brix, at 50 °C). The osmodehydration time, pomegranate-seed water loss, solute gain and weight reduction were determined during the osmodehydration process. The equilibrium time periods of osmodehydration were 20, 60, 80 and 60 min for sucrose solution, and bitter-orange, apple and grape juice concentrates, respectively. The physico-chemical, biological and textural properties of PSs were significantly affected by the changes in OS. At the end of osmodehydration, the dry-matter and the Brix values were higher in all fruit-based OSs compared with sucrose OS. The color of PSs became darker in apple and grape OSs and brighter in bitter-orange OS compared with sucrose OS. On the other hand, all osmodehydrated PSs showed important antioxidant activity, with seeds osmodehydrated in grape-juice OS attaining an IC₅₀ of 49.25 meq GA/100 g DM. All observed changes were attributed to the difference in the composition of the different OS matrices. Moreover, the hedonic analysis showed that consumers preferred osmodehydrated PSs obtained using bitter-orange juice as OS. Full article

Seed banks present in soils provide information on past/existing standing vegetation and the probable future vegetation of the area. We reviewed 187 articles related to seed banks that were published worldwide from 1859 to 2022 to understand the dynamics of soil seed banks. The heterogeneity and biodiversity of most ecosystems appear vulnerable due to the over-exploitation of soil over the years. The studies on seeds present in soil provide knowledge on species cover, which supports the restoration of degraded areas. An interesting feature observed in most references was that species identified in seed banks do not necessarily represent or reflect the standing vegetation—this is attributed to the varied dispersal mechanisms of different species. The most significant contributions of a seed bank are conservation and the provision of propagules to the ecosystem. These banks are critical for identifying the composition and spatial organisation of understorey plant communities in degraded forests following soil disturbances, such as wildfire, harvesting, and/or logging. Regeneration from soil seed banks enables biodiversity recovery in tropical forests. There has been little understanding of the function soil seed banks play in forest restoration, which is critical to the natural regeneration of forest reserves. The impact of invasive alien species and the associated soil seed banks on vegetation dynamics is poorly researched. With landscape restoration gaining significance in the present decade, it becomes exceedingly important to maintain existing vegetation. It is relevant to India, which has international commitments to restore 26 mha of degraded and deforested land by 2030. This review reveals the importance of soil seed banks and their role in the future maintenance of forest cover. Full article

Smallholder farmers around the world obtain their seed from various sources, which can vary over time. In some countries, smallholder farmers are gaining ground as local seed producers and sellers. This study focuses on the seed production and marketing operations, achievements, and challenges of a particular type of such producers—community seed banks—which are new players in the seed market. Pioneer case studies are presented from countries where grain legumes and dryland cereals are important crops: India, Nepal, Uganda, and Zimbabwe. A mixed methodology was used to collect data, including a literature review, focus group discussion, key informant interview, and participatory observation. The case studies demonstrate the viability of community seed banks as seed businesses but becoming successful is not easy and depends on managerial, technical, financial, social, and policy factors. The cases benefitted from strong initial support provided by a committed and experienced organization, as part of a trajectory of nurtured seed development and empowerment. Embedding local seed enterprises in seed sector networks is crucial to creating demand and gaining recognition and support. Government and development organizations could learn from the case study experiences and support programs to foster local seed businesses as key actors in integrated seed sector development. Full article

The correct development of seeds is a pivotal requirement for species preservation. This process depends on the balance between sensing the environmental stimuli/stressors and hormone-mediated transduction, which results in physiological responses. The red and blue regions of the electromagnetic spectrum are known to influence seed dormancy and germination. Here, we report on the effects induced by the blue (peak at 430 nm) and red (peak at 650 nm) regions of the electromagnetic spectrum on seeds from photo- and skotomorphogenetic capsules developed under white, blue, or red light. Regardless of exposure, seeds from skotomorphogenetic capsules showed an almost absent dormancy in association with altered germination kinetics. Conversely, in seeds from photomorphogenetic capsules, the exposure to the blue region induced skotomorphogenetic-like effects, while the exposure to the whole visible range (350–750 nm), as well as to only the red region, showed a dose-related trend. The observed differences appeared to be dependent on the wavelengths in the red and to be based on transduction mechanisms taking place in fruits. While the molecular bases of this differential effect need to be clarified, the results hint at the role played by different light wavelengths and intensities in seed development and germination. These findings may be relevant for applications in crop production and species safeguarding. Full article