scholarly journals The National Tree Seed Centre Celebrates 40 Years

2007 ◽  
Vol 83 (5) ◽  
pp. 719-722
Author(s):  
J D Simpson ◽  
B S.P. Wang

The National Tree Seed Centre has been providing seed of known origin and quality for research for 40 years. Seed is also stored for long-term gene conservation purposes to provide a source of germplasm for future research and restoration. This is particularly important for species facing such threats as insect attack, disease, climate change, or conversion of forest land to non-forest uses. The Centre's inventory focuses on native tree and shrub species, striving to store samples from throughout their ranges. Over 26 000 seed samples have been sent to researchers in 65 countries, 70% of these samples being distributed within Canada. Seed research has always been a component of the Seed Centre's program. One notable accomplishment is the development of the Petawawa Germination Box. The Seed Centre participates in and contributes to activities of the Association of Official Seed Analysts, the International Seed Testing Association, and the IUFRO Seed Physiology and Technology Research Group. Key words: collection, dormancy, ex situ gene conservation, germination, research, seed, storage

Plant Methods ◽  
2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Shidong Yue ◽  
Yu Zhang ◽  
Yi Zhou ◽  
Shaochun Xu ◽  
Shuai Xu ◽  
...  

Abstract Background Seagrass meadows are recognized as critical and among the most vulnerable habitats on the planet. The alarming rates of decline in seagrass meadows have attracted the attention globally. There is an urgent need to develop techniques to restore and preserve these vital coastal ecosystems. So far little work has been done to develop effective long-term storage method for seagrass seeds. The seagrass Zostera japonica Asch. & Graebn is an endangered species in its native range. Here we utilized combinations of different storage times, salinities, and temperature to determine the most appropriate conditions for optimal seed storage. Results Zostera japonica seeds were strongly desiccation sensitive, with a complete loss of viability after 24 h of desiccation. Therefore, long periods of exposure to air should be avoided to minimize seed mortality. In addition, Z. japonica seeds could not endure freezing conditions such as – 5 °C. However, our results indicated that reduced storage temperature to 0 °C could effectively prolong the duration of dormancy of Z. japonica seeds. Seeds stored at 0 °C under a salinity of 40–60 psu showed relatively low seed loss, high seed vigor and fast seed germination, suggesting these to be optimal seed storage conditions. For example, after storage for 540 days (ca. 600 days since the seed collection from reproductive shoots in early October, 2016) at 0 °C under a salinity of 50 psu, seeds still had a considerable vigor, i.e. 57.8 ± 16.8%. Conclusion Our experiments demonstrated that seeds stored at 0 °C under a salinity of 40–60 psu could effectively prolong the duration of dormancy of Z. japonica seeds. The proposed technique is a simple and effective long-term storage method for Z. japonica seeds, which can then be used to aid future conservation, restoration and management of these sensitive and ecologically important habitat formers. The findings may also serve as useful reference for seed storage of other threatened seagrass species and facilitate their ex situ conservation and habitat restoration.


2020 ◽  
Vol 30 (2) ◽  
pp. 101-111
Author(s):  
Rachael M. Davies ◽  
Alice R. Hudson ◽  
John B. Dickie ◽  
Charlotte Cook ◽  
Tom O'Hara ◽  
...  

AbstractUK trees require increased conservation efforts due to sparse and fragmented populations. Ex situ conservation, including seed banking, can be used to better manage these issues. We conducted accelerated ageing tests on seeds of 22 UK native woody species, in order to assess their likely longevity and optimize their conservation in a seed bank. Germination at four ageing time points was determined to construct survival curves, and it was concluded that multiple samples within a species showed comparable responses for most species tested, except for Fraxinus excelsior. Of all species studied, one could be classified as very short-lived, four as short-lived and 17 as medium, with none exceeding the medium category. The most important finding of this manuscript is that although some taxonomic trends were observed, the results indicate the need for caution when making broad conclusions on potential seed storage life at a species, genus or family level. Longevity predictions were compared to actual performance of older collections held in long-term storage at the Millennium Seed Bank, Kew. Although most collections remain high in viability in storage after more than 20 years, for short-lived species at least, there is some indication that accelerated ageing predicts longevity in seed bank conditions. For species with reduced potential longevity, such as Fagus sylvatica and Ulmus glabra, additional storage options are recommended for long-term gene banking.


1998 ◽  
Vol 28 (6) ◽  
pp. 903-910 ◽  
Author(s):  
Tannis Beardmore ◽  
Wendy Vong

Butternut (Juglans cinerea L.) survival is threatened in North America by the fungus Sirococcus clavigignenti-juglandacearum. To date, there is no control for this fungal disease and long-term seed storage, to ensure survival of the species, is not a viable option. Initially, low (0, –5, –10, –15, and –40°C) and ultralow (–196°C, cryopreservation) temperature tolerance of butternut embryonic axes isolated from the nuts collected from one tree was examined. Embryonic axes with approximately 3 mm of cotyledonary tissue attached to the hypocotyl area germinated after exposure to 0, –5, –10, –15, and –40°C for 4 h and to –196°C for 24 h. Percent germination after exposure to 0 and –5°C was 87 and 82%, respectively, and after –10 and –15°C was 29 and 27%, respectively. Thirty-two percent of axes germinated after –40°C, and 36% germinated after exposure to –196°C. Tolerance to –196°C was examined in the embryonic axes isolated from the nuts of 13 other trees. Significant tree-to-tree variation was found in the tolerance of the embryonic axes to low temperature. This variation corresponded to the water content of the embryonic axes; water contents of 4.8% and lower exhibited tolerance to –196°C. Reducing the water content of the embryonic axes by slow desiccation to 4.8% or less resulted in an increased tolerance to –196°C. These results suggest that low and ultralow temperature storage of embryonic axes may be a viable method for butternut ex situ conservation.


2013 ◽  
Vol 61 (1) ◽  
pp. 1 ◽  
Author(s):  
A. D. Crawford ◽  
F. R. Hay ◽  
J. A. Plummer ◽  
R. J. Probert ◽  
K. J. Steadman

Long-term ex-situ seed storage under controlled conditions in gene banks has become an important tool for conserving threatened Australian plants; however, there is scant information about the seed longevity of most species. The aim of the present study was to determine whether the seed longevity of two contrasting Australian species could be modelled using the seed viability equation, and whether the universal temperature constants are applicable to these species. Seeds of Eucalyptus erythrocorys F.Muell. (Myrtaceae) and Xanthorrhoea preissii Endl. (Xanthorrhoeaceae) were aged at moisture contents ranging from 3.9 to 15.7% and temperatures between –20 and 60°C. Survival data were fitted to the seed viability equation in one step and the species constants for each species determined. Both E. erythrocorys and X. preissii seeds exhibited orthodox seed storage behaviour whose longevity could be modelled using the seed viability equation. The viability constants were KE = 8.81, CW = 4.97, CH = 0.0412 and CQ = 0.000379 for E. erythrocorys and KE = 8.77, CW = 5.29, CH = 0.0382 and CQ = 0.000473 for X. preissii. The universal temperature constants could not be used without a significant increase in error. The storage behaviour of these two Australian species is in keeping with that of orthodox species from around the world. Predictions are that E. erythrocorys will be long-lived under gene bank conditions, whereas X. preissii would be moderately long-lived. Current long-term gene bank storage conditions appear suitable for storage of these species; however, recommendations for short-term storage need to be re-evaluated.


2001 ◽  
Vol 49 (5) ◽  
pp. 619 ◽  
Author(s):  
A. L. Batty ◽  
K. W. Dixon ◽  
M. Brundrett ◽  
K. Sivasithamparam

The impact of seed drying, seed storage and development of testing procedures for seed viability assessment was undertaken for a selection of common taxa with congeners that are rare and endangered (Caladenia, Diuris, Pterostylisand Thelymitra). Freshly collected seed showed significantly lower levels of germination compared with seed that had been subjected to drying over silica gel for 24 h. Seed dried over silica gel for 24 h and plunged into liquid nitrogen exhibited a further increase in germination levels. Germination of seed stored at 4, 18 or 22˚C for 1 year was substantially higher than freshly collected seed (4 weeks after dehiscence), but germination was highest overall after storage of dried seed in liquid nitrogen (–196˚C). Mycorrhizal fungi that promote the germination and growth of plants were also successfully preserved in liquid nitrogen. The use of cryoprotectants on fungal isolates had no observable deleterious effects on fungal regeneration. Histochemical staining procedures (tetrazolium, fluorescein diacetate and Evans blue) substantially overestimated seed viability, relative to symbiotic seed germination, for most seed treatments indicating a need for re-evaluation of the effectiveness of staining procedures for testing viability. The implications of the long-term ex situ storage of orchid seed and fungal symbionts for the conservation of endangered orchids is discussed.


2015 ◽  
Vol 20 (4) ◽  
pp. 242-251 ◽  
Author(s):  
Éva Kállay

Abstract. The last several decades have witnessed a substantial increase in the number of individuals suffering from both diagnosable and subsyndromal mental health problems. Consequently, the development of cost-effective treatment methods, accessible to large populations suffering from different forms of mental health problems, became imperative. A very promising intervention is the method of expressive writing (EW), which may be used in both clinically diagnosable cases and subthreshold symptomatology. This method, in which people express their feelings and thoughts related to stressful situations in writing, has been found to improve participants’ long-term psychological, physiological, behavioral, and social functioning. Based on a thorough analysis and synthesis of the published literature (also including most recent meta-analyses), the present paper presents the expressive writing method, its short- and long-term, intra-and interpersonal effects, different situations and conditions in which it has been proven to be effective, the most important mechanisms implied in the process of recovery, advantages, disadvantages, and possible pitfalls of the method, as well as variants of the original technique and future research directions.


2020 ◽  
Author(s):  
Emily Budzynski-Seymour ◽  
James Steele ◽  
Michelle Jones

Physical activity (PA) is considered essential to overall health yet it is consistently reported that children are failing to meet the recommended levels. Due to the bidirectional relationship between affective states and PA, affective responses are a potential predictor to long term engagement. Since late March 2020 the UK government enforced ‘lockdown’ measures to help control the spread of Coronavirus (COVID-19); however, this has impacted children’s PA. Using online resources at home to support PA is now common. The primary aim of this research was to investigate the use of the Change4Life 10-minute Shake Ups to support PA by examining the effects of Disney branding upon children’s (n=32) post activity affective responses and perceived exertion. The secondary was to investigate the effect of the lockdown on PA habits. Children had similar positive affective responses and perceived effort to activities; however, branding was considered to be a key contributing factor based upon qualitative feedback from parents. Children’s PA levels dropped slightly since ‘lockdown’ was imposed; though online resources have been utilised to support PA. The use of immersive elements such as characters and narrative in PA sessions, as well as utilising online resources during ‘lockdown’ appear potentially promising for future research.


2019 ◽  
Vol 20 (3) ◽  
pp. 251-264 ◽  
Author(s):  
Yinlu Feng ◽  
Zifei Yin ◽  
Daniel Zhang ◽  
Arun Srivastava ◽  
Chen Ling

The success of gene and cell therapy in clinic during the past two decades as well as our expanding ability to manipulate these biomaterials are leading to new therapeutic options for a wide range of inherited and acquired diseases. Combining conventional therapies with this emerging field is a promising strategy to treat those previously-thought untreatable diseases. Traditional Chinese medicine (TCM) has evolved for thousands of years in China and still plays an important role in human health. As part of the active ingredients of TCM, proteins and peptides have attracted long-term enthusiasm of researchers. More recently, they have been utilized in gene and cell therapy, resulting in promising novel strategies to treat both cancer and non-cancer diseases. This manuscript presents a critical review on this field, accompanied with perspectives on the challenges and new directions for future research in this emerging frontier.


2020 ◽  
Vol 20 (15) ◽  
pp. 1398-1414 ◽  
Author(s):  
Darby J.E. Lowe ◽  
Daniel J. Müller ◽  
Tony P. George

Ketamine has been shown to be efficacious for the treatment of depression, specifically among individuals who do not respond to first-line treatments. There is still, however, a lack of clarity surrounding the clinical features and response periods across samples that respond to ketamine. This paper systematically reviews published randomized controlled trials that investigate ketamine as an antidepressant intervention in both unipolar and bipolar depression to determine the specific clinical features of the samples across different efficacy periods. Moreover, similarities and differences in clinical characteristics associated with acute versus longer-term drug response are discussed. Similarities across all samples suggest that the population that responds to ketamine’s antidepressant effect has experienced chronic, long-term depression, approaching ketamine treatment as a “last resort”. Moreover, differences between these groups suggest future research to investigate the potential of stronger efficacy towards depression in the context of bipolar disorder compared to major depression, and in participants who undergo antidepressant washout before ketamine administration. From these findings, suggestions for the future direction of ketamine research for depression are formed.


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