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The low quality of plants produced in nurseries has added to the high mortality rates in plantations established in Mexico. The objective of this study is to evaluate the effect of three sowing dates and the provenance of the germplasm on the plant quality of Pinus patula, in addition to evaluating the effectiveness of four pre-germination treatments: i) control, ii) soaking in water for 12-hour and storage at 3 °C for five weeks, plus 12-hour soaking before sowing, iii) storage at 3 °C for five weeks and 12-hour soaking before sowing, and iv) 12-hour soaking before sowing. The height, diameter at the root neck, robustness index, and germination efficiency of the provenance progenies of P. patula in the nursery were evaluated, in addition to daily and accumulated germination in the laboratory. Data were analyzed using ANOVA, Kruskal-Wallis tests, Tukey means, and Dunn's medians. In addition, the response variables were correlated with the bioclimatic variables of the provenances. Statistical differences were found in plant quality according to provenance. Families from Pinal de Amoles, Querétaro presented the lowest robustness index (6,61). The seeds had a higher germination (92,3 %) when soaked for 12 h and stored at 3 °C for five weeks, plus soaking in water for 12 h before sowing. The quality and germination of P. patula are influenced by its provenance, sowing date, and pregerminative treatments. [ABSTRACT FROM AUTHOR]

Despite exhibiting intriguing features associated with its multipurpose applications and drought tolerance, Ferula communis remains a wild and uncultivated species, with limited experimental research on its biology, starting from seed germination and extending to its ecology. The purpose of this study was to investigate potential germination and kinetics in F. communis seeds in response to four cold stratification periods (0, 15, 45, and 90 days at a constant temperature of 5 °C) and four temperatures (5, 10, 15, and 20 °C) under continuous darkness. F. communis exhibited a pronounced germination potential exceeding 90%, with the optimal temperature for germination falling within the range of 5 °C to 15 °C, without necessitating cold stratification. A dramatic drop of the germination percentage was observed at 20 °C (<10%), suggesting a form of conditional dormancy attributed to the higher temperature tested. [ABSTRACT FROM AUTHOR]

Copyright of Anadolu (1300-0225) is the property of Anadolu Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Saskatoon berry has become as important as a commercial fruit crop. One main goal is to release new plant cultivars well adapted to different climatic and soil conditions. Dormant seeds obtained from breeding are serious problems delaying the program. The seeds were directly extracted from fruits after harvest (unstored) or after storage at −18 °C for 6 months (stored) and subjected to modified stratification (3 °C) with KNO3, H2O2, NO, smoke-water (SW) or scarification using sandpaper or H2SO4 for 10, 20, 30, 40 min or treatments with pulsed radio frequency (PRF) or red light. The seeds were also subjected to warm–cool stratification (20/3 °C). Unstored seeds germinated in a higher percentage and with better uniformity (T75–T25) than stored seeds. Stored seeds positively affected the onset of seed germination (T1) and mean germination time (MGT). Dormancy breakage was promoted by stratification with KNO3, SW or scarification with sandpaper, H2SO4 or treatments with PRF. The recommended method for the breeding program of breaking seeds dormancy is when unstored seeds are subjected to stratification in KNO3 (0.2%) or SW (1:100). Depending on the applied methods, the percentage of seeds' germination increased to 87% compared to untreated (64%) control seeds. The positive effects of the selected methods persisted during seedling development by stimulating their growth and enhancing the chlorophyll content index (SPAD) and effective quantum yield of PSII of chlorophyll in leaves (ΦPSII). [ABSTRACT FROM AUTHOR]

Seed dormancy is a complex adaptive trait of plants that are influenced by several physiological and environmental factors. The endangered plant Cinnamomum migao is also known to exhibit seed dormancy and low germination, which may influence its regeneration; however, these characteristics remain unexplored. To our knowledge, this study is the first to examine the type of dormancy and improve the germination percentage of C. migao seeds. We evaluated the structure and characteristics of the embryo and endocarp of C. migao seeds as well as the effects of endogenous inhibitors. Furthermore, we assessed the effects of light, stratification, alternating temperature, and gibberellic acid 3 (GA3) on the dormancy release of these seeds. The embryo was well developed the endocarp was water-permeable, and no obvious mechanical hindrance to germination was observed. However, the endocarp and embryo contained phenols and other germination inhibitors. The seed extracts of C. migao delayed the germination of cabbage and ryegrass seeds, which indicates the presence of endogenous inhibitors. These findings suggest that C. migao seeds exhibit physiological dormancy. Light and an alternating temperature (15/20°C) did not influence germination. However, GA3 pretreatment, alternating temperatures, and warm stratification relieved dormancy. GA3 pretreatment combined with the 15°C stratification treatment was most effective in rapidly releasing the C. migao seed dormancy. Our findings may facilitate the storage and conservation of this endangered plant, which is currently underrepresented in ex situ collections.

Seed dormancy is a complex adaptive trait of plants that are influenced by several physiological and environmental factors. The endangered plant Cinnamomum migao is also known to exhibit seed dormancy and low germination, which may influence its regeneration; however, these characteristics remain unexplored. To our knowledge, this study is the first to examine the type of dormancy and improve the germination percentage of C. migao seeds. We evaluated the structure and characteristics of the embryo and endocarp of C. migao seeds as well as the effects of endogenous inhibitors. Furthermore, we assessed the effects of light, stratification, alternating temperature, and gibberellic acid 3 (GA3) on the dormancy release of these seeds. The embryo was well developed the endocarp was water-permeable, and no obvious mechanical hindrance to germination was observed. However, the endocarp and embryo contained phenols and other germination inhibitors. The seed extracts of C. migao delayed the germination of cabbage and ryegrass seeds, which indicates the presence of endogenous inhibitors. These findings suggest that C. migao seeds exhibit physiological dormancy. Light and an alternating temperature (15/20°C) did not influence germination. However, GA3 pretreatment, alternating temperatures, and warm stratification relieved dormancy. GA3 pretreatment combined with the 15°C stratification treatment was most effective in rapidly releasing the C. migao seed dormancy. Our findings may facilitate the storage and conservation of this endangered plant, which is currently underrepresented in ex situ collections. [ABSTRACT FROM AUTHOR]

Seed dormancy classes determine both population and species-level processes which can be crucial in the life cycle of many plants. However, there are no studies of a dormancy cline between levels of morphophysiological dormancy (MPD). We aimed to determine the class of seed dormancy of Narcissus yepesii exhibits in order to explore links between different dormancy levels, previously characterized in two closely related phylogenetic congeners, N. alcaracensis and N. longispathus. Experiments were carried out under both near-natural temperature and controlled laboratory conditions. The parameters calculated were mean embryo length, radicle and shoot emergence percentages. The effects of different periods of storage; and different periods with or without GA3 of warm, cold or warm plus cold were analysed. The Narcissus populations from the Baetic System of mountain ranges in south-eastern Spain show clinal variation in a northeast–southwest gradient from intermediate to non-deep complex MPD, through the coexistence of intermediate and non-deep complex MPD in N. yepesii (21 % and 74 %, respectively). In addition, 54 % of stored seeds were able to show both levels of MPD. Narcissus yepesii occupies an intermediate position between N. alcaracensis and N. longispathus in the geographical distribution and in the clinal germination ranges. It strongly suggests an evolutionary gradient, which connects the intermediate complex MPD with the non-deep complex MPD in southern Iberian daffodils. This is the first study showing a gradient in the evolution between levels of MPD. Our results demonstrate a cline in these levels in response to both an environmental gradient and genetic differences. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Forestry Society of Croatia / Sumarski List Hrvatskoga Sumarskoga Drustva is the property of Forestry Society of Croatia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Forestry Society of Croatia / Sumarski List Hrvatskoga Sumarskoga Drustva is the property of Forestry Society of Croatia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Seed germination requirements for S. alata were investigated using cold stratification and phytohormones. Treatments included no stratification (control), two week, three week, four week, five week, and six week cold stratification. Hormone treatments included no stratification with cytokinin, no stratification with gibberellins, no stratification with cytokinin and gibberellins, no stratification with auxin, and one with six week stratification with abscisic acid. Three weeks cold stratification was required to yield a significant increase in percent germination. Gibberellin was the only hormone which caused a significant increase in germination in S. alata seeds. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine whether the A horizon (topsoil) exhibits stratification across two depths, 1 cm and 4 cm. Two sites in San Antonio, TX, were chosen to address this question. The first was on the campus of the University of the Incarnate Word. The second was adjacent to the university in the Headwaters Sanctuary. At each locality, soil samples were analyzed in order to examine the morphological diversity of bacteria across site and depth. Preliminary results suggest that the bacterial biodiversity is different when depths are considered as a single entity versus individually. These finding have implications for investigations into soil biodiversity and suggest that in order to gain an accurate estimate of bacterial biodiversity in topsoil multiple depths within this layer of soil should be examined. [ABSTRACT FROM AUTHOR]

Highlights • Photoinhibition of seed germination affected by temperature has been reported. • A fraction of Allium melananthum seeds has a primary non-deep physiological dormancy. • Low temperatures can induce a strong secondary dormancy that prevents germination. • A. melananthum plants can bloom in the second growing season from the sowing of seeds. • A. melananthum plants can produce bulblets in the third growing season from the sowing. Abstract The germination and life cycle of the rare species Allium melananthum , endemic to southeast Spain, were investigated. One alternating and four constant temperature regimes and two light conditions were tested. Gibberellic acid and cold or warm stratification were used as dormancy breaking treatments. The results showed that light can inhibit seed germination, although the light inhibitory effects varied with temperature. In continuous darkness, seed germination was hardly affected by temperature, but in alternating light/darkness it was sensitive to extreme temperatures of 25 and 10 °C, while mild temperatures of 15–20 °C permitted successful germination. However, a dormant stage was observed in a small fraction of seeds, which was only overcome by warm stratification. By contrast, cold stratification induced strong secondary dormancy. This germination pattern shows that primary and secondary dormancy, temperature and light play pivotal roles as components of the germination-timing strategies of A. melananthum. As regards its life cycle, the juvenile phase in a low proportion of individuals (0.93%) lasted 2 years from seeding, while 56.7% of individuals were capable of producing bulblets in the third year. We suggest that at least two growing seasons post seeding are necessary in the nursery to obtain suitable material for the introduction or reinforcement of A. melananthum populations in their natural habitat. [ABSTRACT FROM AUTHOR]

Zanthoxylum nitidum (Roxb.) DC. is one of the most important economic crops on account of its value as a Chinese herbal medicine ( Zanthoxyli radix ), health product and daily chemical raw materials. Zanthoxylum nitidum seeds are characterized to be an intermediate physiological dormancy that requires three months of cold stratification (4 °C) or gibberellin (GA) treatment (300 mg L −1 , soaking for two days) to relieve seed dormancy and promote germination. Exploring the changes of proteins and related biosynthetic and metabolic pathways during seed dormancy release will contribute to expand our knowledge of this process. In this study, mature Zanthoxylum nitidum seeds from Pingyuan County, Guangdong province were treated with cold stratification and GA solution. The differently expressed proteins after treatments were characterized by iTRAQ coupled LC–MS/MS. In total, 484 proteins showed that at least 1.3-fold differences in abundance were detected after treatments; a majority of the differently abundant proteins are involved in the respiration-related metabolism processes, biosynthesis of amino acids and translation during the dormancy release of Zanthoxylum nitidum seeds. This study is the first to use the iTRAQ-based proteomics approach to analyse the proteome of Zanthoxylum nitidum seeds, pointing out the direction for our further research on the pathways and even the key genes and proteins associated with the dormancy release of Zanthoxylum nitidum seeds. [ABSTRACT FROM AUTHOR]

Persimmon (Diospyros kaki) is an important subtropical, monoecious, dioeocious and polygamous tree which belongs to Ebenaceae family. Because of low total seed and low viability seed in persimmon, grafting on seedling rootstock is generally used for its propagation. The common rootstock is Diospyros lotus, but its seeds have long dormancy. So, the study was carried out to investigate the effects of stratification (0, 25, 50 and 70 days) at 4- 7°C, scarification with (97%) sulphuric acid (0, 2.5, 5 and7.5 minute) and GA3 (0, 250, 500 and 750 mgL-1) on seed germination of D. lotus. Results showed that the most germination rate was observed in GA3 at 250 mgL-1. Stratification for 70 days had the most germination percent. The most germination uniformity was observed in GA3 at 500 mgL-1. In scarification plus stratification, the germination percent was lower than control and stratification. [ABSTRACT FROM AUTHOR]

The Mexican yew (Taxus globosa) is important for the production of taxol, which is used to treat several types of cancer and its seeds undergo a latent period. The objectives of this research were to study the causes of seed dormancy in this species, the types of dormancy mechanisms it undergoes and how to break such dormancy. Seeds from two regions of Mexico (northern and central region) were evaluated using 12 pre-germination treatments. The treatments consisted of warm and cold stratification, applying 500 ppm of gibberellic acid (GA4/7) at different intervals, or using alternative seed scarification methods. In addition, embryo growth was studied and a protocol for in vitro embryo culture was also tested. Seeds from the central region did not germinate, probably because of inbreeding depression in seeds that came from small fragmented populations. In contrast, seeds from the northern region of Mexico subjected to warm plus cold stratification, warm plus cold stratification plus GA4/7 application, and warm stratification plus stratification with N2 plus GA4/7 application exhibited the highest germination rates (12-14 %). In vitro embryo culture indicated that only 30% of the embryos germinated. Thus, dormancy in the Mexican Yew seems to be caused by several factors, including both morphological and physiological factors. [ABSTRACT FROM AUTHOR]

Propagation of European hazelnut by seed is influenced by some seed treatments. In this investigation, effect of stratification period and some chemicals on seeds of four hazelnut cultivars were studied. GA3 and four months of stratification, each individually resulted in the highest germination percentage at 82.73% and 83.75%, respectively. There were significant differences between cultivars and treatments in terms of germination percentage and rate. The highest germination percentage and rate were observed in the local cultivar Gerd under GA3 treatment at 100 mg/L and also after four months of stratification. [ABSTRACT FROM AUTHOR]

Using a complete factorial, randomized block design, the effects of seed density (430 or 860 seeds/m2), seed stratification (stratified, non-stratified), split planting (complete seed mix planted in spring vs. non-aggressive species in spring and aggressive species in fall), and distance to groundwater (−5 or − 30 cm) were studied in a mesocosm complex in central Iowa. All 16 treatment combinations were replicated 5 times for a total of 80 mesocosms. The seed mix sown contained 25 species. At the end of the study, groundwater levels had the greatest effect on species richness, total shoot density, and total biomass. Seed stratification, seed density and delayed planting all had a significant impact on species richness and total shoot density. Delaying the planting of aggressive species significantly increased total shoot densities and biomass of non-aggressive species. Of the 20 species actually found in the mesocosms, 12 had higher shoot densities in the delayed planting, 11 in the high groundwater, 7 in the stratified seed, and 3 in the high seed density treatment. Overall, groundwater level and delayed planting of aggressive species had the largest impact on species diversity and shoot density. [ABSTRACT FROM AUTHOR]

Mexican bean weevil, Zabrotes subfasciatus Boheman, is a significant pest of stored beans (Phaseolus vulgaris L.) that causes considerable loss in the quality and quantity of bean grain in Africa. In the past two to three decades, researchers have attempted to identify botanicals with better insecticidal potential against storage pests. However, there is a lack of information on the potency of botanical combinations, their toxicology, and optimal application rates. This study was conducted to examine the bioefficacy of unitary and binary botanical combinations of Jatropha curcas (L.), Datura stramonium (L.), Chenopodium ambrosioides (L.), Schinus molle (L.), and Azadirachta indica (A. Juss) against Z. subfasciatus at 1% and 2% w/w dosages. The insecticidal activities of the botanicals were measured based on their effect on adult mortality of Z. subfasciatus and progeny reduction, grain weight loss, and weevil perforation index. Among botanical admixtures, binary combinations of C. ambrosioides + D. stramonium , J. curcas + C. ambrosioides , and S. molle + C. ambrosioides were the most potent. They resulted in the highest mortality of Z. subfasciatus , low weevil perforation index or none, and grain weight loss at the most moderate test dosage (1% w/w). Treatment with C. ambrosioides resulted in the highest efficacy when applied individually. We failed to observe any notable difference in toxicity between dosage levels among the binary botanical combinations. However, the effectiveness of unitary formulations improved with the increase in dosage rate. Application of botanicals did not adversely affect bean seed germination. Our study suggests that botanicals in binary mixtures may enhance the potency of constituent components for effective control of Z. subfasciatus. [ABSTRACT FROM AUTHOR]

We present our techniques for producing blue elderberry (Sambucus nigra L. ssp. cerulea (Raf.) Bolli [Adoxaceae]) from seeds at a container nursery in northern Idaho. By applying a gibberellic acid treatment combined with a cold, moist stratification we are able to reliably break seed dormancy and produce an annual crop of seedlings that are 30 cm (12 in) tall with a root collar diameter > 4 mm (0.16 in). [ABSTRACT FROM AUTHOR]

Many seeds of woody plants require low temperature for germination and that’s called seed dormancy has been investigated for relations of proteins by several researchers. We determined polypeptide profiles of cold-stratified Mazzard seeds. Seeds were studied in five different periods: seeds in dormancy (none stratified), 30, 60, 90 and 120 days cold-stratified. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE) of the soluble protein fractions from stratified and none stratified seeds was utilized for determination of changes in polypeptides. SDS-PAGE revealed a decrease in the concentrations of 14 polypeptides and appearance of four low-molecular weight (15.1, 16.3, 17.8 and 19.4 kDa) polypeptides were determined in 90 and 120 day stratified seeds. The study results exhibited the evidences of the involvement of protein changes in response of Mazzard seeds during cold stratification. [ABSTRACT FROM AUTHOR]

One of the rarer problems that occur in growing medicinal and spice plants is ensuring the quality of the propagating material. Germination of seeds of one of these plants, Allium ursinum L., is slow. To improve that, stratification is used. In the experiment, which was carried out in Lithuania in 2016, evaluation of four-and five-week long stratification and the use of alkaline ionized (pH 8.6) water for germination affect for Allium ursinum L. seeds were evaluated. It was found that the above-mentioned intervals for stratification did not affect the beginning of seed germination. Furthermore, one of the possible reasons for slower germination was found, and it was the incidence of seed diseases caused by fungi and bacteria. Allium ursinum L. seeds were affected the most by Penicillium ssp. micromycetes. The longer the period of stratification, the more alkaline ionized water decreased the effect of Mucor ssp. Micromycetes. [ABSTRACT FROM AUTHOR]

Summary: Although the effects of cold stratification on the release of physiological dormancy in seeds have been studied extensively, knowledge of the role of soil moisture content on seed dormancy release during cold stratification is limited. Our study determined seed dormancy characteristics and the effect of soil moisture content on seed dormancy breakage during cold stratification in the five common weed species Amaranthus retroflexus, Chenopodium album, Chenopodium hybridum, Plantago lanceolata and Setaria glauca. Seeds of all five species were dormant at the time of harvest and their germination response to light and temperature varied. Soil moisture content had a significant effect on seed dormancy release of all species except P. lanceolata. Germination percentage of A. retroflexus, C. album, C. hybridum increased and then decreased as soil moisture content increased, regardless of germination test temperature. The optimal soil moisture content and seed moisture content for dormancy breakage of A. retroflexus, C. album, C. hybridum were 8%, 12%, 8% and 22.0%, 37.7%, 25.7% respectively. Dry storage (after‐ripening) significantly increased germination of S. glauca. Moreover, increasing soil moisture content first slowed and then increased dormancy breakage in S. glauca. These results suggest that data on soil moisture content should be incorporated into models that predict weed seed dormancy breakage and timing of seedling emergence as well as those for weed management. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Kirkuk University for Agricultural Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Eleocharis carniolica is included in the EU Habitat Directive and legally protected in many European countries. It is also considered as one of the most threatened plants in Poland. It typically occurs in muddy habitats, wet meadows, lake or pond shores or temporary puddles, but in Poland this species usually occurs at disturbed anthropogenic sites such as road verges or drainage ditches. Despite being the focus of a number of ecological and conservation studies, E. carniolica still does not have a fully recognized ecology and life-strategy, particularly with regard to breaking seed dormancy and germination. To find out the population performance and species propagation potential in Poland, we have conducted experiments aimed at assessing the seed germination conditions and efficiency. The main goal was to discover the crucial factors that stimulate germination. The results of the experiments suggest that light is a pivotal factor for triggering germination of E. carniolica seeds. Moreover, E. carniolica's seed bank consisted of about 80 % dormant seeds. The only effective method for dormancy breaking was warm stratification (placing the seeds at high temperature on a moist substrate) with application of gibberellic acid (GA 3) , and even a few days of warm stratification resulted in effectively overcoming dormancy. Eleocharis carniolica's germination features are typical for plants adapted to frequent disturbances with a short life expectancy and large reproductive effort. Our results strongly suggest that E. carniolica has a ruderal life strategy at its northern distribution limits and probably can be considered as an alien species in Poland. • light is a crucial factor for triggering germination of E. carniolica seed. • E. carniolica creates a diverse seed bank consisting of about 80 % dormant seeds. • germination features are typical for plants adapted to frequent disturbances. • E. carniolica has a ruderal life strategy in its northern limits and probably can be regarded as an alien plant in Poland. [ABSTRACT FROM AUTHOR]

Thalictrum uchiyamae Nakai is an herbaceous perennial plant that has potential for greater utilization for landscaping and medicinal purposes. In the present study, we investigated some of the factors that affect seed dormancy and germination in this species. To determine the temperature requirements for embryo growth and germination in field conditions, the seeds were buried in field soil. Every 1 or 2 weeks, the seeds were exhumed, and embryo growth, germination, and seedling emergence were investigated. In the laboratory, the effects of temperature and GA 3 on dormancy break and germination were investigated in order to characterize the seed dormancy. The seeds had underdeveloped embryos that were physiologically dormant at maturity in late September. In natural conditions, embryo growth and germination occurred in March of the following year, and seedlings emerged in early April. The physiological dormancy of the embryos was broken by cold stratification at 5 °C for 8 weeks, but warm temperatures (25/15 °C) were required to promote embryo elongation even after the physiological dormancy was broken. GA 3 treatment could substitute for the cold stratification requirements and broke seed dormancy of T. uchiyamae , 87.3% of which germinated after 8 weeks of incubation at 25/15 °C at 100 mg ⋅L −1 GA 3 soaking treatment. These results suggest that the seeds of T. uchiyamae exist in a state of non-deep simple morphophysiological dormancy. The temperature requirements for the dormancy break of the seeds enabled the seedlings to emerge in the very beginning of the growing season the following year. These results represent practical knowledge for propagation of these plants from seed. [ABSTRACT FROM AUTHOR]

Understanding the key aspects of plant regeneration from seeds is crucial in assessing species assembly to their habitats. However, the regenerative traits of seed dormancy and germination are underrepresented in this context. In the alpine zone, the large species and microhabitat diversity provide an ideal context to assess habitat-related regenerative strategies. To this end, seeds of 53 species growing in alpine siliceous and calcareous habitats (6230 and 6170 of EU Directive 92/43, respectively) were exposed to different temperature treatments under controlled laboratory conditions. Germination strategies in each habitat were identified by clustering with k-means. Then, phylogenetic least squares correlations (PGLS) were fitted to assess germination and dormancy differences between species' main habitat (calcareous and siliceous), microhabitat (grasslands, heaths, rocky, and species with no specific microhabitats), and chorology (arctic-alpine and continental). Calcareous and siliceous grasslands significantly differ in their germination behaviour with a slow, mostly overwinter germination and high germination under all conditions, respectively. Species with high overwinter germination occurs mostly in heaths and have an arctic-alpine distribution. Meanwhile, species with low or high germinability in general inhabit in grasslands or have no specific microhabitat (they belong to generalist), respectively. Alpine species use different germination strategies depending on habitat provenance, species' main microhabitat, and chorotype. Such differences may reflect adaptations to local environmental conditions and highlight the functional role of germination and dormancy in community ecology. [ABSTRACT FROM AUTHOR]

The bilberry ( Vaccinium myrtillus L.) is a spontaneous dwarf shrub with potential for national and international markets due to food and medicinal uses of its fruits, being considered an important source of sugars, antioxidants, vitamins and minerals. Request for bilberry fruits are on the rise, but the land area covered in bilberry bushes and locally collected berries have declined in Central Italian Apennine regions in recent last decades. The objective of this study was to assess the most suitable conditions for in vivo and in vitro seed germination in order to improve the reproductive performance of this species under artificial and controlled environments. Freshly matured bilberry seeds were tested for germination before and after cold stratification and air-room storage under different light conditions and temperatures. Seeds were then in vivo and in vitro germinated on different soil types and culture media. Fresh seeds showed a better germination capacity (76%) than stratified ones, being 16-h photoperiod and air temperatures of 22.5 °C the optimal conditions for germination. At 25 °C the germination rate decreased to 66% and very few seeds (8%) germinated at 15 °C. Darkness always had a negative influence on the germination capacity. However, after cold stratification germination increased significantly at 15 °C, both in light (51%) and darkness (24%); thus, seeds of this species are conditionally dormant at maturity. Although the effect was different depending on temperature and light condition, cold seed stratification had an overall negative effect on all the considered germination parameters, and seed viability was strongly reduced after storage at room temperature for 90 days. Soil type and culture media did not significantly affect the final germination percentage (≈62 and 78%) in the in vivo and in vitro trials performed on fresh non stratified seeds, respectively. Nevertheless V. myrtillus turf ( in vivo experiment) and modified MS medium ( in vitro experiment) gave rise to the most germination in the shortest time. Temperature proved to be the most influential physical factor on bilberry seed germination. Seedlings obtained from in vivo experiments showed good development. [ABSTRACT FROM AUTHOR]

Alien grape ( Vitis, Vitaceae) species and recently described hybrids are recognised as major environmental weeds in southern Europe, based on their tendency to spread into natural and semi-natural habitats, often behaving as invasive species. Despite a high number of agronomic, genetic and phytopathological studies on Vitis cultivars, regeneration from seed has been poorly investigated, although it plays a key role in plant distribution and evolution. To this end, in this study we exposed seeds of eight wild grapes in Europe (three species and five nothospecies, including the native Vitis vinifera), to different temperature treatments in the laboratory. Fresh seeds from all studied taxa were dormant and germinated only after cold and/or warm plus cold stratification, but showing significant differences between the species. Seeds of V. vinifera showed an intermediate complex morphophysiological dormancy, while all other tested Vitis taxa exhibited a deep complex morphophysiological dormancy. Dark conditions reduced the germination percentage in Vitis labrusca, Vitis riparia and V. vinifera and their hybrids, and alternating temperatures elicited the highest germination percentages in all populations. Our results demonstrated for the first time that Vitis hybrids are capable of regeneration by seed, even in the absence of dispersal by animals. The germination processes studied here help understand the current expansion of alien Vitis taxa in Europe outside the viticultural areas. Consequently, germination requirements contribute to a better understanding of the mechanisms underlying alien Vitis taxa establishment and invasion. [ABSTRACT FROM AUTHOR]

We studied species richness and community composition as well as the vertical distribution of ferns and lycophytes in three forest types along an elevational gradient in the region of Los Tuxtlas, Mexico. We established 23 plots of 20 m x 20 m at 150–1650 m, recording presence-absence of all species in eight vertical distribution zones (terrestrial and seven epiphytic zones). We found 84 species, including 79 ferns and five lycophytes. Species richness patterns differed markedly between different vertical zones, with the forest understory having a high diversity of epiphytes, many of which were specialized to this habitat. Overall species richness increased with elevation, but the richness of ground-living, terrestrial species showed the lowest elevational increase by only 50%, whereas epiphytic richness increased fourfold to tenfold. These differences presumably reflect the stronger influence of increasing environmental humidity on the water-limited epiphytic assemblages. We also found that the degree of habitat specialization of epiphytes decreased with elevation. This probably is due to decreasing tree height and increasing overall humidity, reducing the microclimatic differences between the forest interior and canopy. This elevational decrease in habitat specialization raises important questions as to, e.g., the strength of competitive interactions or the possibility that the evolutionary transition from terrestrial to epiphytic growth forms is more easily achieved at higher elevations. [ABSTRACT FROM AUTHOR]

Salinity is a major environmental stress factor for crop production and is an extensive limitation for seed germination. A germination test was carried out with four replications and three levels of salt concentrations (0 dS.m-1, 6 dS.m-1 and 12 dS.m-1) in plastic tray under quartz granules. Analysis of variance (ANOVA) indicated that all traits were significance (P < 0.01) for genotypes, treatment and their interaction. Germination percentage (GP), germination speed (GS), germination index (GI), maximum root length (MRL), maximum shoot length (MSL), total dry matter (TDM), and salt tolerance index (STI), seed vigor index (SVI) were all decreased as the level of NaCl was increased. Mean germination time (MGT) and Percent reduction in dry weight over control (ROC%) was increased as the NaCl concentration increased. From the result, it is concluded that 962, Super gold, Kaveri-50, PAC-999, 9120, 900M Gold and C-6485 hybrids would be tolerant while prince articulated as salt sensitive. [ABSTRACT FROM AUTHOR]

Vaccinium vitis-idaea L. (Ericaceae) and Vaccinium myrtilloides Michx. are important agronomic and ecological species. Several food products are derived from these species throughout Europe and North America, and they are becoming important plants for land reclamation. Several studies have indicated that stratification can be beneficial for the germination of Vaccinium seed species including V. vitis-idaea and V. myrtilloides; however, the recommended stratification lengths vary from 12 wk to 10 mo. This study investigated the optimal time for cold stratification of V. vitis-idaea and V. myrtilloides seeds collected in Alberta, Canada. Seed treatments consisted of unstratified as well as 2, 4, and 8-wk stratification periods. Our results indicate that the 8-wk cold stratification period provided the highest mean germination and uniformity for V. vitis-idaea, but mean germination time was longer compared to the other stratification treatments. Moreover, 8-wk stratified V. myrtilloides seeds showed the lowest average germination percentage and the least amount of synchronization. Similar studies involving V. vitis-idaea presented comparable findings to this study but further studies are required to determine stratification strategies for V. myrtilloides. Further research of V. myrtilloides seed characteristics, such as dormancy, may be beneficial for gaining a better understanding of the effects of stratification on germination. [ABSTRACT FROM AUTHOR]

The present study was carried out on 315 breedable sows of approximately 2-4 years of age irrespective of parity with good body condition in varying managemental conditions under subtropical rainfall areas of Meghalaya. These animals were fed on kitchen wastes with locally available green fodder. The animals those were non return after one month (range 28-34 days) post-breeding, were grouped as positive group (n=215), non-mated pigs as negative group (n=100) and distilled water as control group (n=100). Urine samples were collected in clean, sterilized plastic containers through manual method at farmer's door during natural micturition in the morning and diluted at the ratio of 1:4 with distilled water for pregnancy diagnosis on the same day of collection. Wheat seed with average 85% of germination after 48 h at room temperature was selected for the entire study. In each sterile petri dish, 15 wheat seeds were taken on the blotting paper and 15 ml of diluted urine was added and covered with trays to avoid evaporation, and kept undisturbed for 48 h at room temperature. Test was conducted in triplicate for each animal. Control test was also carried out with the addition of distilled water only to the wheat seeds. The germination inhibition percentage and shoot length (cm) of germinated seeds in each petri dish was recorded and calculated at 48, 72 and 96 h after adding the sample. All data were analysed using two-way ANOVA by SPSS software and expressed as Mean±SE. The mean germination inhibition percentage of wheat seeds was significantly different between pregnant (75.66±3.48), non-pregnant (28.70±2.96) and control (19.48±2.69) groups. Shoot length (cm) was significantly less in pregnant group when compared to non pregnant and control groups, and also significantly different within the group at different time intervals. Mean germination inhibition percentage and reduced shoot length in positive group was indicative of pregnancy status. Hence, it can be concluded that seed germination inhibition is a useful technique to detect pregnancy in pigs as a simple, non-invasive and cost effective method, and must be popularized among the farmers, veterinary officers and paraveterinary workers for field level application. [ABSTRACT FROM AUTHOR]

Seeds of Bunium persicum (Boiss.) B. Fedtsch. have complex physiological dormancy that can be released by 15 weeks stratification. The present study revealed that cold stratification enhanced content of HO, O and application of GA and ROS donors (Fenton reagent, HO, methylviologen and menadione) did not affect or only slightly promoted the germination of non-stratified, fully dormant seeds. Dormancy was markedly decreased by ROS-generating reagents, GA and fluridone (an inhibitor of ABA biosynthesis) and was enhanced by ROS-decreasing compounds (DMTU, Tiron, SB and DPI), diniconazole (Dinc, an inhibitor of ABA catabolism) and paclobutrazol (PAC, an inhibitor of GA biosynthesis) when dormancy was partially removed by cold stratification. The response to these compounds reduced with increasing time of stratification. ABA inhibited germination by repressing of NADPH oxidase activity and ROS accumulation and conversely, GA triggered germination by promoting an increase of NADPH oxidase activity and ROS levels. Data in this study, for the first time suggest releasing deep complex physiological dormancy by cold stratification is associated with interplay between ROS and ABA/GA. [ABSTRACT FROM AUTHOR]

Effects of immersing seeds in water and X-ray imagining on germination of Corylopsis seed were investigated. Seeds that sank or floated were collected after immersing in water for 5 min, 4 h or 16 h, and germinated with or without 5°C cold stratification (CS). In C. coreana and C. sinensis var. calvescens, 52% and 89%, respectively, of seeds that sank immediately developed embryos and cotyledons germinated. Germination of C. sinensis var. calvescens seeds that sank after 16 h increased to 45% after the first CS treatment, as compared to 12% without CS. Immersing seeds in water for 16 h to collect full and mostly full seeds is recommended. X-ray imaging coupled with immersion is effective technique to select viable seeds. Dormancy could be partially released by immersing seeds in water for 16 h; however, germination was improved after CS. [ABSTRACT FROM AUTHOR]

We present quantitative measurements and mathematical analysis of the granular drag reduction by rotation, as motivated by the digging of Erodium and Pelargonium seeds. The seeds create a motion to dig into soil before germination using their moisture-responsive awns, which are originally helical shaped but reversibly deform to a linear configuration in a humid environment. We show that the rotation greatly lowers the resistance of soil against penetration because grain rearrangements near the intruder change the force chain network. We find a general correlation for the drag reduction by relative slip, leading to a mathematical model for the granular drag of a rotating intruder. In addition to shedding light on the mechanics of a rotating body in granular media, this work can guide us to design robots working in granular media with enhanced maneuverability. [ABSTRACT FROM AUTHOR]

Germination strategy is an essential mechanism that determines plant survival in previously established populations or newly colonised sites. Carex is a group of species that has shown difficulties to germinate experimentally and also many of them failed in order to use in restoration projects. Our aim was to determine whether Carex elata and C. elongata that dominate in vegetation of Central European swamps differ in their germination strategy. We conducted germination experiments with stratified and unstratified seeds of both species to determine: 1) if they are able to germinate fresh, 2) if they exhibit a cyclic dormancy pattern, and 3) if they will germinate from a seed bank. We demonstrate fresh seed germination and no evidence of cyclic dormancy in either species. Stratification did not enhance final germination but it did accelerate germination. Seed bank seeds of both species germinate sparsely. We demonstrate that these coexisting Carex species differ with respect to final germination. The higher germination percentages of the fresh seeds compared to buried and seed bank seeds of both species probably reflect adaptation to fluctuating water-level conditions. In summary, these findings support a strategy of fresh germination in a highly-variable environment. Our study indicates that both C. elata and C. elongata are suitable for restoration projects. Successful establishment and revegetation with C. elongata may result simply from sowing fresh seeds. In contrast, seed sowing, combined with vegetatively produced seedling transplants is essential for the successful restoration of C. elata. [ABSTRACT FROM AUTHOR]

Cottonseed yield data of 17 genotypes, of which two genotypes contributed to more than 30% of the total ecovalence, and grown in 23 locations, were used to compare four methods of disjoint environmental stratification: a) environmental index (Ie): favorable or unfavorable environments; b) stratification in partitions that maximize the sum of squares of the genotype x partition interaction [(GP)m]; c) environmental scores of the second principal component of the GGE analysis (PC2-GGE); d) environmental scores of the first principal component of the AMMI analysis (PC1-AMMI). Scenarios were simulated (10,000 simulations per scenario) using combination of nine or 13 environments and 11 genotypes, either including or excluding those with the highest ecovalence values. In all scenarios, the greatest selection gains were obtained via PC2-GGE stratification, and the lowest selection gains were obtained via Ie. The ecovalences of the genotypes influenced the results obtained using the stratification methods. [ABSTRACT FROM AUTHOR]

There are several different opinions regarding dormancy in tea ( Camellia sinensis L.), but there is no strong evidence available to conclude whether or not these seeds are dormant. Freshly matured tea seeds collected from Hangzhou, China, at the natural dispersal time did not germinate in light at daily alternative temperature regimes of 10/15, 15/20, 20/25, or 25/35 °C, or at a constant temperature of 25 °C. Seeds were permeable to water and the embryos did not grow prior to radicle emergence, thus, the seeds have no physical, morphological, or morphophysiological dormancy. When cold-stratified at 4 °C for 1, 2, and 3 months, 64%, 88%, and 93% of the seeds germinated, respectively. Intact fresh seeds failed to germinate after treatment with 0, 10, 500, and 1000 ppm GA3, whereas 3%, 4%, 61%, and 86% of cracked seeds germinated, respectively. Thus, the seeds have nondeep and intermediate physiological dormancy. Seeds cold-stratified for 2 months that were buried at soil depths of 0, 1, and 5 cm in pots showed that seeds at 1 cm depth established significantly higher number of seedlings ( P < 0.05) than at other two depths. Because tea seeds are susceptible to summer temperature drying, these seeds do not establish a persistent seed bank. [ABSTRACT FROM AUTHOR]

Leymus chinensis has important forage value and is considered a useful grass species for grassland restoration in Northeast China. However, little information exists concerning the germination responses of this species to interactions of cold stratification, light, temperature and low water potential caused by salinity and drought. Experiments were conducted in growth chambers, and the results showed that in all conditions of light, temperature and water stresses, the germination percentages of cold-stratified seeds were higher than of non-stratified seeds. Light had an inhibitory effect on germination percentage under both non-saline and salt stress conditions; darkness is beneficial for germination of this species. In addition, seeds germinated much better under alternating temperature regimes than under constant temperatures. Both salt and drought stresses decreased the germination percentage of Leymus chinensis, but the reductions under drought stress were much greater. Moreover, after being transferred to distilled water, most non-germinated seeds under drought stress germinated well, and the total percentage reached that of the non-saline condition level. Therefore, cold stratification is an effective measure to increase seed germination and salt or drought tolerance, especially in darkness. We conclude that Leymus chinensis has definite salt and drought tolerance during the germination stage and it is a promising species for the restoration of deteriorated grassland in Northeast China. [ABSTRACT FROM AUTHOR]

This study was conducted in the forestry department nursery of Mosul University; to investigate the effects of stratification degrees & chilling on seed germination and seedlings growth of Pistacia khinjuk stock. The results revealed the superiority of seed stratification in 12°c stratification in comparison with 4°c stratification. the 12°c gave the higher averages of germination energy (%) , germination percentage (%) , Survival percentage (%) , Seedling length (cm.) & seedling diameter (mm), the averages were 26.96%, 36.39 % , 34.74% , 54.54 cm, 5.90mm respectively , Also the stratificated seeds for 20 days were superior in all characters and gave the highest average in germination energy 34.42% , germination percentage 49.80% survival percentage 46.36%, seedling length 55.41 cm., and seedling diameter 6.1 mm. The chilling period 48 hour was superior in characters of germination energy (29.95%) , germination percentage (40.33%) , Survival percentage (38.16%) , Seedling length (64.09)cm. and seedling diameter (6.37)mm.

Monitoring of browse utilization of plant communities is consistently recommended as an important component of monitoring moose (Alces alces) populations across regions. We monitored winter browse utilization by moose within a willow (Salix spp.) -dominated winter range of Montana in 2008-2010.We sought to improve our understanding of: 1) spatiotemporal heterogeneity of intensity of moose browsing across the winter range, 2) species-specific selection of willow by moose during winter, and 3) appropriate sample sizes, placement, and stratification of monitoring sites for estimating browse utilization. During 3 consecutive winters we monitored 108-111 transect segments, each 50 m in length, in a systematic distribution across willow communities and assessed the effects of covariates potentially predictive of variation in browsing. Mean annual estimated browse utilization across all segments was 11.5% of sampled twigs in 2008 (95% CI = 9.4 - 13.7%), 8.0% in 2009 (95% CI = 6.2 - 9.8%), and 8.3% in 2010 (95% CI = 6.5 - 10.1%). Modeling of variation in browse utilization revealed positive relationships with the proportion of preferred species (β = 0.44, P = 0.05) and previously browsed willow plants (β = 3.13, P < 0.001), and a negative relationship with willow patch width (β = -0.002, P < 0.001). We found that planeleaf (Salix planifolia), Wolf's (S. wolfii), and Booth's willow (S. boothii) were the most consistently preferred species, whereas Drummond's (S. drummondiana) and Geyer willow (S. geyeriana) willow were moderately preferred; Lemmon's willow (S. lemmonii) was used less than expected. Power analyses indicated that detecting a 10% increase in browse utilization with 95% confidence in consecutive years required measuring 38-41, 50-m segments. Because systems with low and heterogeneous browse utilization of willow present challenges for efficient monitoring, we encourage power analyses as a means of evaluating sampling protocols, in addition to consideration of covariates predictive of spatiotemporal heterogeneity. [ABSTRACT FROM AUTHOR]

The objective of this work was to quantify changes in the germination capacity ofJuglans nigraseeds following storage and then artificial stratification. Seeds were stored at 5 and –20 °C under 5% and 14% internal moisture content (IMC) for 0, 8, 10, and 12 months under conditions with oxygen or under vacuum. Germination percentage (GP) was affected by storage temperature, IMC, and storage period. Seeds stored with 5% IMC succeeded in germinating regardless of the temperature. Seeds stored with 14% IMC did not germinate (–20 °C) or germinated during storage (5 °C). The GP was reduced with the time of storage in seeds at –20 °C and 5% IMC and this effect was avoided in storage under vacuum. In conclusion, the germination capacity of black walnut seeds did not change for up to 12 months at low above-zero temperature and low IMC (5 °C, 5% IMC), being the most cost-effective alternative for long-term storage of black walnut seeds in commercial nurseries. Vacuum storage avoided the decrease of around 50% in average germination capacity of seeds stored for a year at –20 °C. [ABSTRACT FROM PUBLISHER]

Peanut is one of the annual crops grown in both arid and semi arid areas whose germination can be affected by high temperatures. The effect of heat stress on seed germination and seedling vigor was investigated. Seeds were kept in sealed laminated aluminium foil bags and exposed to heat stress for 48 h at four temperatures; 27±2°C, 70±5; RH (control: room temperature), 40°C, 50°C, and 60°C. Seed germination and seed vigor decreased significantly as the heat stress temperature increased. The seed moisture content and total abnormal seedlings did not vary among treatments whereas occurrence of deformed seedlings was significant at temperatures greater than 40±1°C. However, 40°C significantly induced dormancy by 31% compared to the control seeds, while heat stress beyond 50°C had detrimental effect on peanut seeds in the form of embryonic death. [ABSTRACT FROM AUTHOR]

Seed germination of the kiwifruit (Actinidia deliciosa A. Chev. C.F. Liang and A.R. Ferguson), a deciduous, perennial vine, is low because of seed dormancy. The main purpose of this study was to characterize kiwifruit seed dormancy and germination in response to environmental factors such as temperature and light. Dormancy of hydrated seeds is alleviated by the perception of a period at low temperatures (stratification) of at least 3 weeks at 2 or 5°C. Alleviation of dormancy is accomplished by incubation at fluctuating temperatures (20/30°C). A red light pulse did not affect germination, whereas a far-red light pulse strongly inhibited germination. This inhibition was readily reverted by a second pulse of red light, indicating that phytochromes are also involved in dormancy alleviation. Although seed germination was inhibited by the fruit pulp, the latter prevented neither perception of low temperature nor changes in the light sensitivity of the seeds. Therefore, it can be advanced that kiwifruit seeds will only germinate after dispersal if the time–temperature requirement for dormancy alleviation and fluctuating temperatures for dormancy termination are fulfilled. Perception of a closed canopy might interfere with dormancy termination. [ABSTRACT FROM PUBLISHER]

Seed germination is comprehensively regulated by multiple intrinsic and extrinsic factors, and reactive oxygen species (ROS) are relatively new among these factors. However, the role and underlying mechanisms of ROS in germination regulation remain largely unknown. In this study, we initially found that cold stratification could promote germination and respiration of Hedysarum scoparium seeds, especially at low temperature. We then noted that a ROS environment change induced by hydrogen peroxide (H 2 O 2 ) or methylviologen (MV) could similarly promote seed germination. On the other hand, the ROS scavenger N-acetyl-L-cysteine (NAC) suppressed germination of cold-stratified H. scoparium seeds, indicating a stimulatory role of ROS upon seed germination. An increased accumulation of O 2 − was detected in embryonic axes of cold-stratified seeds, and stratification-induced ROS generation as well as progressive accumulation of ROS during germination was further confirmed at the cellular level by confocal microscopy. Moreover, protein carbonylation in cold-stratified seeds was enhanced during germination, which was reversed by NAC treatment. Finally, the relationship between ROS and abscisic acid (ABA) or gibberellin (GA) in germination regulation was investigated. ABA treatment significantly inhibited germination and reduced the H 2 O 2 content in both cold-stratified and non-cold-stratified seeds. Furthermore, we found that cold stratification mediates the down-regulation of the ABA content and increase of GA, suggesting an interaction between ROS and ABA/GA. These results in H. scoparium shed new light on the positive role of ROS and their cross-talk between plant hormones in seed germination. [ABSTRACT FROM AUTHOR]

Tanoak Lithocarpus hancei (Fagaceae) is one of the dominant species in the high diversity subtropical evergreen broad-leaved forests in SW China. However, seedlings of L. hancei and other oaks are quite rare in the understorey. To investigate the effects of seed (acorn) predation and seedling herbivory by mammals, and litter, on acorn germination and seedling survival of L. hancei in these forests, we set up a 2 × 2 factorial experiment (litter present or removed; ±herbivore exclosures (fences); plus natural control; 5 replications) in the Ailaoshan National Nature Reserve, central Yunnan from 2010 to 2015. Acorns and transplanted seedlings of L. hancei were placed in the four treatments plots and the influence of these treatments on acorn germination and seedling survival was monitored. Fences protected L. hancei acorns and seedlings against herbivory by rodents and other mammals; litter had a positive effect on acorn survival but no effect on seedling establishment. Moreover, those seedlings that escaped herbivory were mostly killed by fungal attack. Our results indicate that while litter and pathogens have some influence, herbivores are probably the major cause of the low frequency of L. hancei seedlings in the understorey. [ABSTRACT FROM AUTHOR]

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As a wild apple species native to central Asia, Malus sieversii (Ledeb.) Roem. is distributed in a wide region covering most of the Tienshan Mountains. Malus sieversii is a useful genetic pool for apple breeding since rich with diversity. In this paper, we first describe the species range of this endangered species. We then describe an in situ reserve that has been established. We also investigated some reproductive characteristics of M. sieversii including pollen germination, seed dormancy, and seed viability. Both stratification and seedcoat removal efficiently released seed dormancy and accelerated seed germination. Pollen germination rate is around 60%. Our data suggest that injurious insects and human activities, rather than reproductive characters, limit the renewal of M. sieversii. [ABSTRACT FROM AUTHOR]

Ochradenus baccatus is a perennial glycophyte growing in Middle East and it is one of the most important food sources for many animal species in desert regions. The aim of our study was to investigate the effects of seed storage, light, temperature and gibberellic acid (GA3) on germination of O. baccatus seeds. We also investigated the germination characteristics of O. baccatus seeds under different saline concentration and their capability to recover germination once they were transferred to distilled water. Seeds were stored at room temperature (20 ± 2 °C) and at -18 °C. Germination tests were conducted at alternating temperatures of 15/25, 20/30 and 25/35 °C in either continuous darkness or photoperiod of 12-h dark/12-h light. To study the effect of GA3 on germination of O. baccatus seeds, freshly-collected seeds and stored seeds were soaked for 24 h in a GA3 water solution (1 g/L) before sowing. To assess the salinity tolerance during germination, seeds were germinated under different salinity levels (100, 200 and 400 mM NaCl). Stored seeds at room temperature and -18 °C germinate equally well at different temperature regimes and light conditions. However, freshly matured seeds were not able to germinate even when they were treated with GA3. On the contrary, stored seeds at room temperature and -18 °C treated with GA3 increase the final germination percentages. These results indicated that O. baccatus seeds have physiological dormancy and they need to be stored in order to break their dormancy. In the present study, one year of storage did not show a significant variation in germination between the two storage conditions assayed. Therefore, further research is needed to know about the maximum storage period for O. baccatus seeds under different storage conditions. Very few O. baccatus seeds (less than 5%) germinated at the tested lowest concentration of NaCl. However, ungerminated seeds were able to germinate when salinity stress was alleviated. In conclusion, O. baccatus seeds have physiological dormancy, and seed storage (at room temperature and at -18 °C) for one year is effective for breaking this dormancy. In addition, O. baccatus seeds present ability to remain viable in saline conditions and they will be able to germinate once the salinity level decrease. Rev. Biol. Trop. 64 (3): 965-974. Epub 2016 September 01. [ABSTRACT FROM AUTHOR]