As part of conservation of plant genetic resources, long-term storage of seeds is highly relevant for genebanks. Here we present a systematic review and a meta-analysis of studies on seed longevity focusing on half-life (P 50) under different storage conditions. Six studies were selected for the meta-analysis; in addition, a high number of additional references were included in the discussion of the results. The results show that under ambient conditions, half-life is short, from 5 to 10 years, while under more optimal conditions, which for orthodox seeds is at low humidity and low temperature, half-life is more in the 40−60 years range, although with large interspecies variation. Under longterm genebank conditions, with seeds dried to equilibrium and thereafter kept at minus 18 −20°C in waterproof bags or jars, half-life can be twice or three times as long. In general, many of the grain legume seeds, as well as corn, common oat, and common barley are long-lived, while cereal rye, onion, garden lettuce, pepper, and some of the forage grasses are more short-lived. Conditions during maturation and harvesting influence longevity, and proper maturation and gentle handling are known to be of importance. Seed longevity models have been developed to predict final germination based on initial viability, temperature, humidity, storage time, and species information. We compared predicted germination to results from the long-term experiments. The predicted values were higher or much higher than the observed values, which demonstrate that something in the seed handling in the genebanks have not been optimal. Long-term studies are now available with data at least up to 60 years of storage. Our review shows that the knowledge and methodology developed for the conservation of plant genetic resources should also work for wild species of orthodox seed nature.

Aim To contribute directly to Norway's national and international commitments to systematic, long‐term conservation of crop wild relatives (CWR) by ensuring both the in situ and ex situ protection and availability of a broad range of CWR genetic diversity within the country. Location Norway. Methods We created a priority list of CWR within Norway based upon four main criteria including economic value from national to global level of associated crops and inclusion in Annex 1 of the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA). Species presence data were gathered from the Global Biodiversity Information Facility (GBIF) and used for predictive species distribution modelling in MaxEnt. capfitogen software was utilized to create an ecogeographic land characterization (ELC) map and to identify complementary in situ genetic reserves and ex situ collecting priorities which target the full range of ecogeographic diversity of taxa. Results An inventory of 204 priority CWR within Norway was compiled. A grid cell complementary network of 19 in situ areas (~10 km2) conserved 201 priority CWR, and a separate analysis identified a protected area complementary network of 23 reserves that conserved 181 priority taxa. For ex situ conservation, 177 taxa did not have ex situ accessions and of the 24 with accessions, 15 had the minimum of five populations conserved throughout their ecogeographic range. Main conclusions We present the first comprehensive national recommendations for in situ and ex situ conservation of 204 priority CWR in Norway. Proposals target the conservation of the ecogeographic diversity of the priority CWR and hence their genetic diversity. Both the priority taxa and the methodology used are applicable at regional and global scales with the recommendations not only helping Norway to meet its international obligations for conservation of genetic diversity of CWR but also ensuring this genetic diversity is available for use in tackling global food security.

Apple genetic resources in Norway are currently conserved within a number of local clonal archives. However, during establishment of these ex situ collections, primary focus was not on capturing as much of the diversity as possible, but instead on preserving cultivars of particular importance to specific fruit-growing areas. To identify redundancies within the collection as well as to assess the genetic diversity and structure of apple germplasm currently being conserved in Norway, eight microsatellites were used in genetic characterization of 181 apple accessions. Overall, 14 cases of synonym or possibly mislabeled accessions were identified, as well as several homonyms and duplicates within and among the analyzed collections. The information obtained should contribute to overall better management of the preserved germplasm. Bayesian analysis of genetic structure revealed two major clusters, one containing most of the foreign cultivars, while the other consisted mainly of traditional Scandinavian cultivars, but also some very winter-hardy genotypes such as ‘Charlamovsky’, ‘Gravenstein’, ‘Transparente Blanche’, and ‘Wealthy’. Analyses of molecular variance (AMOVA) detected a significant genetic differentiation among the clusters (fCT = 0.077; P < 0.01). The results of the Bayesian analyses do not indicate a strong differentiation between the foreign and the Norwegian apple accessions, however, they do suggest that climate adaptation has had a significant influence on the genetic structure of the preserved germplasm. Overall, apple accessions currently maintained ex situ in Norway represent a diverse germplasm which could be very valuable in future breeding programs, especially for the Scandinavian climate.

Crop wild relatives (CWR) can provide one solution to future challenges on food security, sustainable agriculture and adaptation to climate change. Diversity found in CWR can be essential for adapting crops to these new demands. Since the need to improve in situ conservation of CWR has been recognized by the Convention on Biological Diversity (CBD) (2010) and the Global Strategy for Plant Conservation (2011–2020), it is important to develop ways to safeguard these important genetic resources. The Nordic flora includes many species related to food, forage and other crop groups, but little has been done to systematically secure these important wild resources. A Nordic regional approach to CWR conservation planning provided opportunities to network, find synergies, share knowledge, plan the conservation and give policy inputs on a regional level. A comprehensive CWR checklist for the Nordic region was generated and then prioritized by socio-economic value and utilization potential. Nordic CWR checklist was formed of 2553 taxa related to crop plants. Out of these, 114 taxa including 83 species were prioritized representing vegetable, cereal, fruit, berry, nut and forage crop groups. The in situ conservation planning of the priority CWR included ecogeographic and complementarity analyses to identify a potential network of genetic reserve sites in the region. Altogether 971,633 occurrence records of the priority species were analysed. A minimum number of sites within and outside existing conservation areas were identified that had the potential to support a maximum number of target species of maximum intraspecific diversity.