Seed Storage Temperature Research Articles

Viability and integrity of Pinus densiflora seeds stored for 20years at three different temperatures.

Storage temperature is one of the most important factors determining seed longevity in the genebank. This study aimed to investigate the effect of storage temperature on the seed viability and physiological integrity after a 20-year storage period of Pinus densiflora, a tree species of ecological and economic significance in South Korea. To this end, seeds were collected and stored dry for 20years at -18°C, 4°C and 25°C. Germination tests were conducted to assess seed viability and vigour, electrolyte leakage analysis was performed to assess cell membrane integrity, and carbohydrate analysis was conducted to assess metabolic integrity during germination. The results revealed that over 20years, seeds stored at -18°C maintained a high germination percentage (GP; 89%), comparable to initial GP (91%), whilst those stored at 4°C exhibited a decline in GP (44%) along with a decrease in vigour. Seeds stored at 25°C lost their viability entirely. Electrical conductivity of the leachate and leakage of inorganic compounds and soluble sugars were higher with elevated storage temperature, indicating increased imbibition damage. Additionally, changes in carbohydrate content during germination revealed that the loss of viability according to storage temperature is associated with reduced storage reserve utilization and altered carbohydrate metabolism during germination. These results enhance our understanding of the effect of seed storage temperature on longevity and physiological changes of aging in the genebank, serving as a reference for establishing conservation strategies for Pinus densiflora.

Effect of storage temperature and packing materials on seed germination and seed storage behavior of Schefflera abyssinica

Abstract. Bareke T, Addi A, Roba K, Kumsa T. 2022. Effect of storage temperature and packing materials on seed germination and seed storage behavior of Schefflera abyssinica. Nusantara Bioscience 14: 141-147. Knowledge of seed storage behavior is crucial for developing appropriate ex-situ conservation strategies. The main objective of this study was to determine the seed storage behavior of Schefflera abyssinica (Hochst. ex A. Rich.). A factorial combination of three temperatures (-10, 0, and 22°C) levels, two types of packing containers (polythene bag and aluminum bag), and eight periods of storage (0, 30, 60, 90, 120, 150, 180 days, and for a year) level was used to determine the germination capacity and storage behavior of the seeds. Accordingly, seed storage temperatures and storage period (up to 1 year) have a significant effect on the germination (p<0.01) of S. abyssinica. The highest average germination percentage of S. abyssinica seeds was obtained after 2 months of storage under all conditions. The seed storage period influences the germination of S. abyssinica by 47.8%. The germination percentages of S. abyssinica seeds have shown significant differences in storage temperatures. Seeds stored at -10°C showed the highest germination percentage in all storage periods compared to the two storage temperatures. Generally, the highest germination capacity of S. abyssinica seeds was between 7% and 9% moisture content after 60 and 90 days of storage. Packing materials have no significant difference in the survival of seeds. No stored seeds germinated after one year of storage at room temperature, 0°C, and -10°C. Based on the definition of seed storage behavior, we conclude that seeds of S. abyssinica have intermediate storage.

Pengaruh Hormon terhadap Induksi Embrio Somatik Kacapiring (Gardenia jasminoides) dan Potensi Aplikasinya dalam Pembuatan Benih Sintetik

Kacapiring (Gardenia jasminoides) is an ornamental plant that has many uses, as a cut flowers, food ingredients, textile materials, cosmetic raw materials, and containing therapeutic compounds. The high demand for gardenia needs to be balanced with the results of its cultivation. Conventional propagation of gardenias has disadvantages such as a long life cycle, genotypes can differ from the parent, and can carry disease from the parent. Therefore, more efficient gardenia propagation techniques are needed, one of which is by making synthetic seeds. Synthetic seeds can be produced by encapsulating somatic embryos. Somatic embryos are collections of embryonic cells formed from soma cells that have the ability to regenerate into a complete new plant. Hormones are organic materials that occur naturally in plants or are synthetic. Hormones have an effect on plant differentiation and growth. Somatic embryogenesis can be carried out using auxin and cytokinin hormones, because auxins can induce embryogenic callus and cytokinins can initiate the embryogenic process in callus. Synthetic seeds are single somatic embryos covered by a matrix, so that they can be stored for a certain duration of time and can grow into a complete plant in both in vitro and ex vitro conditions. This literature review is to provide an overview based on existing references on the effects of various types of hormones for the induction of gardenia somatic embryos, synthetic seed production methods, and synthetic seed storage temperatures.

Effect of Desiccation and Storage Environment on Longevity of Ehretia cymosa Thonn. Seeds

Globally, forestry faces challenges in the availability of seeds due to limited knowledge on seed handling of various species. Forestry seeds are constantly being reviewed and classified as either recalcitrant, intermediate, or orthodox based on their storage behavior. It is essential to understand the tree seed storage behavior to maintain seed viability and thus minimize seed losses. There is scanty literature combining factors of seed moisture content (6%, 9%, 12%, 15%, and 20%), seed storage temperature (20oC, 5oC and -20oC), seed storage duration (1, 4, 9 and 12 months), and germination in different sites with varying environmental variables. Ehretia cymosa is important in the Afromontane forestry landscape as a medicinal, rehabilitation, and conservation species. This study conducted desiccation and storage studies and their influence on the viability of E. cymosa seeds. The study sought to determine the optimum conditions for the storage of Ehretia cymosa that maintains viability. This study observed that E. cymosa dried to seed moisture content of 6%, stored for 12 months at 20oC and sown in the laboratory had the highest germination performance (27.6 ± 3.18%) (p<0.05). This confirms that E. cymosa seeds exhibit orthodox storage behavior. The authors recommend longer storage studies (>12months) to determine the actual longevity of the seeds of this species. The significance of these results would be useful for foresters and farmers that would need to use this species for various purposes.

EFFECT OF STORAGE TEMPERATURE AND CULTIVARS ON SEED GERMINATION OF Lilium×formolongi HORT.

An experiment was carried out to evaluate the influences of seed storage temperature and variation due to cultivars on the germination of the Lilium×formolongi hort. seeds. The seeds of four cultivars of Lilium×formolongi Hort. viz. Augusta, Raizan Herald (RH), Eorayeon 1ho, and Eorayeon 2ho was treated with four temperature ranges 5°C, -2°C, -20°C and 20°C (Room temperature, Control) up to 6 months to execute the experiment. In total 500 seeds of each cultivar including four temperature regimes and four replications for each temperature treatment and each replication represented by 30 seeds have been provided 10 days chilling treatment before to test the germination to get the uniformity in germination. The laboratory experiment was carried out in a completely randomized design (CRD) to assess the different parameters of germination viz. germination percentage(GP), mean germination time (MGT), germination index (GI), time taken to 50% germination (T50), and coefficient of the velocity of germination (CVG) at four temperature regime of four cultivars. The ANOVA analysis revealed significant variability among the four cultivars for all germination parameters in all temperature treatment levels. The results of the experiment demonstrated that the storage temperature has a great influence on germination percentage (GP), mean germination time (MGT), germination index (GI), time taken to 50% germination (T50), and coefficient of the velocity of germination (CVG) with comparisons to the normal temperature stored seeds (20°C). The significant variation among these parameters for each cultivar demonstrated the significance of varied requirements like stored temperature for the long term storage of that particular cultivar.

The quality of cold-pressed rapeseed oil obtained from seeds of Brassica napus L. with increased moisture content.

The basic parameter influencing the quality of cold-pressed oil is the quality of seeds used  for pressing. Adverse moisture content and storage temperature of rape seeds may affect the quality of oil obtained from them. This paper presents the effects of increased rapeseed moisture content on the quality of the oil pressed. The material used for the tests was rapeseed (canola) cv. PR 46 W14. The moisture content of the seeds was adjusted to 10%, 12% and 20%, and the seeds were stored at room temperature for 14 days. The samples were then dried to a seed moisture equal to 7% and oil was pressed from them. Acid and peroxide values, as well as the content of water, tocopherols and phenolic acids, were determined. In addition, a sensory analysis of the oil samples was carried out, and structural changes in the association colloids in the oil were determined using a fluorescent probe. With the increase in seed moisture, the increase in peroxide and acid values of the analyzed oils was recorded. A slight decrease in tocopherol content and a significant increase in phenolic acid concentration, depending on the seed moisture content, was observed. Sensory analysis showed odor sensory profile changes that probably indicate microflora development. The rapeseed moisture content has a crucial influence on the quality of oil obtained from them. Along with an increase in seed moisture, the possibility of developing undesirable microflora grows, which results in a deterioration in the quality of the obtained oil.

Does synthetic seed storage at higher temperature reduce reserpine content of Rauvolfia serpentina (L.) Benth. ex Kurz.?

In the present study, we analyzed the impact of storage temperature and storage duration of synthetic seeds of Rauvolfia serpentina (L.) Benth. ex Kurz. on their germination performance and reserpine content, its key secondary metabolite. Synthetic seeds were developed using in vitro shoot tips (3–4 mm long) polymerized with 3% (w/v) sodium alginate and 75 mM calcium chloride. Storage of synthetic seeds at 25 °C exhibited a high frequency of germination (82%) after 30-day storage. However, longer storage period (60 days) drastically reduced the germination frequency of synthetic seeds to 36%. Alternatively, in case of 8 °C storage temperature, 60% synthetic seeds were germinated after 30-day storage with a minor decline to 52% following 60-day storage. Moreover, synthetic seed-germinated plantlets from 25 °C storage condition showed a regression in reserpine content (203.38 ± 0.21 µg gm−1 of dried sample) than that of the plantlets regenerated from 8 °C storage (249.37 ± 0.21 µg gm−1 of dried sample). Our study clearly infers that a lower temperature condition (above freezing; 8 °C) is appropriate for storage, post-storage germination, and upholding the reserpine content of R. serpentina synthetic seeds.

Physiological and Biochemical Parameters of Lupin Seed Subjected to 29 Years of Storage

Physiological and biochemical changes resulting from long‐term storage of lupin (Lupinus luteus L.) seed were studied in a precisely controlled experiment to gain a better knowledge of the seed deterioration process. The seed was stored at different temperatures (0, −14, and +20°C) during a 29‐yr period. It was found that after long‐term storage at −14 and 0°C, the seed germinated well, whereas seed stored at +20°C did not germinate at all. The contents of albumin, biogenic amines, and soluble carbohydrates were determined. The content of albumin decreased in seed stored at +20°C. In two‐dimensional electrophoresis of seed proteins, 343 spots were obtained with seed stored at −14°C, whereas the extract of seed stored at +20°C gave 290 spots. Out of all detected spots, 27 displayed significant differences in intensity related to seed storage temperature (−14, 0, +20°C). The identified 27 proteins could be assigned to four major functional categories: storage proteins, proteins connected with defense mechanisms, proteins responsible for energy reactions, and proteins involved in growth and development. Spermine, spermidine, and putrescine were also analyzed in stored seed. The content of biogenic amines was higher in seed stored at +20°C. Significant changes occurred in the content of soluble carbohydrates during seed storage. In seed stored at +20°C, verbascose did not occur and the total content of raffinose family oligosaccharides decreased. The content of reducing monosaccharides and sucrose increased. The results show that lupin seed storage at −14 and 0°C resulted in very similar levels of physiological and biochemical changes, affecting the germination rate, proteome, biogenic amines, and soluble carbohydrates, whereas storage at +20°C is incomparably more detrimental.

Storage duration and temperature of hydroprimed seeds affects some growth indices and yield of wheat.

One of the methods for achieving more yields is to use seed priming technique correctly. When it comes to using seed priming, practically important issues should be taken into account including interval between priming to planting and conditions for storage of primed seeds. Thus, it is very crucial to be informed of duration and temperature for storage of primed seeds. This research seeks to compare the effect of temperature and duration of hydroprimed wheat seeds (var Kouhdasht) on growth indices and grain yield. This test was carried out with three replications in Research Farm of Agricultural Faculty of Lorestan University, as completely randomized block design. The relevant factors include storage temperature (15, 20 and 25° C) and storage duration of hydroprimed seed (0, 2, 4, 6, and 8 days). The results showed that hydropriming increased number of productive spike and grain yield. Nevertheless, delay (8 days storage) in planting and storage seeds at high temperature (25° C) could decrease benefits of priming. Storage temperature and duration of hydroprimed seeds affect morpho-physiological characteristics as well as yield. Seeds stored at 15 and 20° C showed a better yield than those stored at 25° C. Primed seeds stored at 20° C for 2 days showed a better performance than the other applied treatments.

Effect of seed storage temperature on fine root development and mycorrhizal colonization of young Populus nigra seedlings

Abstract Key message Seed storage temperature influences root anatomy of the endangered Populus nigra, and consequently may alter nutrient absorption. A lower temperature during seed storage (−20 and −196 °C) may preserve the potential for a suitable root system development after germination. Context Seed storage conditions can be an important determinant of later seedling growth of Populus nigra L., an endangered tree species. Aims We tested whether long-term seed storage temperature, −10, −20 or −196 °C, affects the pattern of seedling root traits responsible for resource acquisition as compared to seedlings of fresh seeds. Methods We analysed the morphology, anatomy, degree of mycorrhizal colonization, and biochemical composition of roots developed from seed stored for 24 months at five different temperatures (from 3 to −196 °C) commonly used to preserve genetic resources. Results Except for root anatomy, we found no relationship between seed storage temperature and the root traits of seedlings. Among the various storage conditions, the proportion of roots with primary development in the first four orders was similar in seedlings developed from fresh seeds of from seeds stored at −196 or −20 °C. Nitrogen content in the roots was positively correlated with the proportion of (i) roots with primary development and (ii) the cortex width in the root diameter. Conclusions Higher temperatures during seed storage reduced the proportion of roots with absorptive function (with primary development). Therefore, for preservation of P. nigra seeds we recommend lower temperatures such as −20 and −196 °C.

Influence of Growth Temperatures of S almonella and Storage Temperatures of Alfalfa Seeds on Heat Inactivation of the Pathogen during Heat Treatment

Sprouts have been implicated in several outbreaks of salmonellosis in the United States, where the seeds are thought to be the primary source of contamination. The objectives of this study were to investigate the influence of growth temperatures of Salmonella and storage temperatures of alfalfa seeds on heat inactivation of the pathogen on seeds. Alfalfa seeds were inoculated with a composite of Salmonella, grown at temperatures of 15, 25, 35 or 40C, stored at 22C for 7 days, dry heated at 65C for up to 48 h, chilled and subsequently microbiologically analyzed. The heat resistance of Salmonella at 65C (D65) varied with the growth temperatures in the order of 15C > 25C > 35C > 40C. The effect of storage temperature of seeds on heat inactivation of Salmonella was subsequently investigated. Inoculated seeds were dried, stored for 7 days at different temperatures (22, 15, 10, 4, 0, −10 or −18C) and then heat-treated at 60, 65 or 70C. Heat inactivation of Salmonella was dependent on the storage temperature and increased in the order of 0C ≈ −18C > 4C > 10C ≈ −10C > 15C > 22C. Storage at −18 or 0C followed by dry heating at 60 for 72 h consistently inactivated the pathogen to below detectable levels (<0.7 log cfu/g) and did not significantly (P > 0.05) reduce the sprouting yield of seeds compared to their untreated counterparts. These observations will be useful when developing effective strategies and practices to enhance the microbiological safety of alfalfa sprouts. Practical Applications Sprouts are very young shoots of plants often consumed raw in salads or sandwiches. Common sprouts include mung bean, soybean and alfalfa sprouts. Unfortunately, alfalfa sprouts have been implicated in outbreaks of gastrointestinal illness where the seeds themselves are contaminated with important disease-causing microorganisms. In this study, the influence of growth temperature of Salmonella and the storage temperature of seeds on the susceptibility of the disease-causing microorganism to heat was investigated. Storage of seeds in the refrigerator or freezer for a week prior to heating for 3 days completely destroyed the microorganisms and did not have any considerable impact on the seed viability. These observations will be useful for the sprouting industry to design and optimize heat processes to improve the safety of alfalfa sprouts.

Factors Influencing the Dry Heat Sensitivity of Salmonella enterica on Alfalfa Sprouting Seeds

AbstractSprouts have been implicated in several outbreaks of salmonellosis where the seeds were found to be the likely source of contamination. The aims of this study were to assess the efficacy of heat to eliminate Salmonella on alfalfa seeds as affected by the water activity of seeds, inoculum strain(s) of Salmonella, storage temperature of seeds and heat treatment duration. Thermal inactivation of Salmonella at 65C was less effective in seeds of reduced water activity of 0.3 or 0.5 compared with 0.6. Prior freezing of inoculated seeds enhanced heat inactivation of Salmonella in seeds with an elevated water activity of 0.6, but not for seeds with a water activity of 0.3–0.5. Salmonella DT104 and a cocktail of four typical strains of Salmonella were more heat resistant than Salmonella Senftenberg 775W regardless of the storage temperature. Heat treatment (65C) of durations ranging from 8 to 48 h of seeds (aw ∼0.6), previously kept at freezing or refrigeration temperatures, resulted in complete elimination of Salmonella irrespective of the strains tested. Freezing of seeds (aw ∼0.6) followed by heating at 65C for 6–8 h did not significantly reduce the germinability of seeds although the yield was significantly impaired (P &lt; 0.05).Practical ApplicationsSprouts have been implicated in the outbreaks of salmonellosis where seeds were found to be the likely source of contamination. The effect of water activity, inoculum strain(s) of Salmonella, storage temperature and treatment duration on the lethality of the heat treatment of seeds was investigated. A decrease in the seed water activity from 0.6 to 0.3 resulted in a considerable decrease in the efficacy of the thermal treatment. There was an appreciable difference in the extent of heat inactivation of the different strains, suggesting the importance of using strain cocktails in inactivation studies. Storage of seeds (aw of 0.6) at freezing temperature followed by heating at 65C for 6–8 h reduced the load of Salmonella to undetectable levels although the sprouting yield was greatly reduced. Findings from this study highlight the important intrinsic and extrinsic parameters that need to be optimized for effective pathogen load reduction and viability retention of seeds.

종자저장온도 및 전처리가 야생 하늘타리와 노랑하늘타리의 종자발아 및 유묘 생육특성에 미치는 영향

This study was conducted to determine the effects of seed storage temperature and pre-treatment on seed germination, seedling quality and vigor index of wild Trichosanthes kirilowii and Trichosanthes kirilowii var. japonica. As a result the highest germination rate of T. kirilowii was the 95% at seed stored in room temperature and then soaking for 24 hours in dH₂O. And the highest germination rate of T. kirilowii var. japonica was 96% at seed stored in 2℃ and then soaking for 24 hours in GA₃ (100 ppm). But the seed germination rate was non-significance in pre-treatment at seed stored in room temperature 2℃. Seedlings of T. kirilowii and T. kirilowii var. japonica showed not only the best seedling quality but also seedling vigor index in seed stored at 2℃ and then soaking for 24 hours in GA₃ (100 ppm). In this research, T. kirilowii and T. kirilowii var. japonica seed were stored in room temperature or 2℃, and then sown in peat moss, seed germination rate was more than 90% and production of superior quality seedlings.

쥐오줌풀 개화·결실 특성과 적정 채종방법 및 육묘이식재배에 관한 연구

This study was carried out to know the characteristics of flowering and bearing fruit, the optimum period, regions and methods for seed harvesting, the optimum temperatures for seed storage and germination, and the optimum period for sowing at nursery bed and seedling transplanting of Valeriana fauriei Briquet. The flowering and bearing fruit of Valeriana fauriei was developed from the before-year root. Optimum period for seed harvest of Valeriana fauriei was from late July to middle August, and optimum areas were the high elevated areas over 500 m above the sea level as Jinbu-myeon, Pyeongchang-gun, Gangwon-do. Using of net-bag for seed harvesting was the effective method to gather the full ripe seed, and bagging of net-bag was necessary from the season of middle May that was the flowering middle-stage. Germination rates don`t show the difference among the different temperatures of storage as approximately 41% at -20℃, 2℃ or 20℃ of seed storage temperatures. The optimum temperature range was in 15 ~ 30℃ for seed germination at nursery bed. The optimum period for seed sowing at nursery bed was the late February, and the optimum period for seedling transplanting was the middle April.

STORAGE STABILITY USING CRYOPRESERVATION: A CASE STUDY IN PAPAYA

ISHS XXVIII International Horticultural Congress on Science and Horticulture for People (IHC2010): III International Symposium on Plant Genetic Resources STORAGE STABILITY USING CRYOPRESERVATION: A CASE STUDY IN PAPAYA

Teste de condutividade elétrica na avaliação de sementes de girassol armazenadas sob diferentes temperaturas

A deterioração é um dos grandes problemas do armazenamento de sementes, principalmente das oleaginosas. Estudos recentes têm evidenciado que a eficiência do teste de condutividade elétrica pode ser influenciada pela temperatura de armazenamento das sementes. Este fato sugere que a deterioração da semente, principalmente em baixas temperaturas de armazenamento, pode não estar relacionada diretamente com a perda da integridade das membranas celulares. Para investigar o efeito de diferentes temperaturas de armazenamento sobre os resultados do teste de condutividade elétrica em sementes de girassol (Helianthus annuus L.), sementes dos híbridos Helio 250 e Helio 251 foram embaladas em papel Kraft multifoliado e armazenadas nas temperaturas: 10 e 25 °C (constante) e 25 °C por seis meses e depois transferidas para 10 ºC até o final do período de armazenamento, sendo que a cada três meses, num total de doze meses, a qualidade fisiológica das sementes foi avaliada pelos testes de germinação, emergência de plântulas, envelhecimento acelerado, condutividade elétrica. Também foi determinado o teor de água das sementes. O teste de condutividade elétrica não é eficiente na detecção do processo de deterioração em sementes de girassol armazenadas sob baixa temperatura.

Temperature during soybean seed storage and the amount of electrolytes of soaked seeds solution

The electrical conductivity test measures the electrolytes that leach out of seeds when they are immersed in water and this leakage is an indication of seed vigor. The level of standardization reached by the procedures of this test is such that the test is recommended for pea seeds and suggested for other large seeded legumes, including soybean [Glycine max (L.) Merrill]. This study was conducted to contribute to the standardization of this test for soybean seeds by verifying whether the seed storage temperature influences the composition of the leachate from soaked seeds solution. Two soybean seed lots of distinct physiological potential were stored in moisture-proof containers either at constant temperatures of 10ºC and 20ºC or at the temperature of 20ºC during the first seven months of storage followed by a change to 10ºC for the rest of the storage time (nine months). The chemical composition of the soaked water was evaluated every three months from January to October 1998. The highest amount of leakage was observed for potassium, followed by calcium and magnesium, iron and sodium regardless of temperature and storage period. The amount of electrolytes in the soaked water increased as the period of time and the temperature of storage increased. On the other hand the amount of leakage decrease along the time for those seeds stored at 10ºC or transferred from the temperature of 20 to that of 10ºC. The temperature at which soybean seeds remain during storage may affect the amount of electrolytes in the soaked water and consequently the results of the electrical conductivity test.

Efeito da temperatura de armazenamento e de fitoreguladores na germinação de sementes de maracujá doce e desenvolvimento inicial de mudas

The germination of sweet passion fruit seeds has problems. Studies that explain and verify its viability are important for seed producers to improve their income and profit. The aim of this work was to verify the effect of storage temperature and imbibition in phytoregulators and KNO2 on germination and seedling development of passion fruit. The experiment was carried out at Casa de Vegetação from Faculdade de Engenharia de Ilha Solteira/Unesp, São Paulo State, using a completely randomized design in a 2 (storage temperature of seeds (room temperature and refrigerator)) x 5 (imbibition treatments (without imbibition, distilled water, gibberelin 250 ppm, cytokinin 250 ppm and KNO3 0.1%)) factorial scheme, with four repetitions. The seeds were stored for 20 days, following imbibition for 24 hours. Evaluations were done until 62 days after sowing. Germination percentage, germination speed and seeds initial development were evaluated. The low temperature had positive effect on germination. The gibberelin positively affected the seeds initial development. The gibberelin effect can be perfectly replaced by low temperature of seed storage.

Effect of Scarification, Seed Storage Temperature, and Relative Humidity on Lupinus havardii Wats. and Lupinus texensis Hook. Seed Germination

Seeds of Lupinus havardii Wats. and L. texensis Hook. were subjected to scarification, storage temperature (4 or 22 °C), and relative humidity (RH) treatments (11%, 23%, 52%, 75%, or 97% RH) for 12 months. Seed moisture increased as relative humidity increased with scarified seed having the greatest increase in seed moisture content regardless of storage temperature. For both species, the combination of seed scarification before storage, 75% RH, and 22 °C storage temperature resulted in a significant and rapid decline in germinability beginning at 4 months. Scarified L. texensis seed stored at 52% RH and 22 °C also exhibited a significant decline in germinability following 6 months storage. Seed of both species stored under all other conditions germinated similar to or higher than the initial germination rate after 12 months. These results clearly show that scarification can be performed before seed packaging as long as the seed packets are stored at ≤23% RH under 4 or 22 °C with no loss in germinability for at least 1 year.

Propagation of native Arctic and alpine species with a restoration potential

Arctic and alpine plant communities today are subject to an increasing frequency and intensity of anthropogenic disturbances. Good understanding of reproductive behaviour and regenerative capacity of native species is important in a restoration situation following human disturbance in Arctic and alpine vegetation. Seeds, bulbils or cuttings from 12 native Arctic and alpine species were collected from Longyearbyen in Svalbard and Dovre Mountain on the Norwegian mainland. Propagation ability was tested in greenhouse conditions. Seeds of Papaver dahlianum, Oxyria digyna, Luzula arcuata ssp. confusa, and bulbils of Bistorta vivipara all had more than 50% germination. Dryas octopetala had less than 10% germination. Both quick and slow germinators were identified among the tested species. Seed storage temperature (+4 °C, ?1 °C and ?20 °C) showed no overall effect on germination. The rooting capacity of cuttings from evergreen and deciduous species was tested. Arctostaphylos uvaursi, Empetrum nigrum ssp. hermaphroditum, Vaccinium vitis-idaea, Salix herbacea and S. polaris had more than 70% rooting ability, while Dryas octopetala and Cassiope tetragona had less than 10%. Saxifraga oppositifolia showed large variation in rooting ability, ranging from 20-90%. The species with high germination and rooting ability are used in an extended restoration experiment in the study areas.