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Members of the genus Atropa contain various tropane alkaloids, including atropine ((±)-hyoscyamine) and scopolamine, which possess medicinal properties. Preserving the diverse genetic background of wild populations via optimal plant production from seeds could be essential for avoiding the loss of potential uses. We analyzed the germination ecology of two Atropa species comprising the threatened A. baetica and widespread A. belladonna to determine the: (1) influence of temperature, light, and seed age on germination patterns; (2) effects of cold stratification and gibberellic acid (GA3); (3) phenology of seedling emergence in outdoor conditions; (4) phenology of dormancy break and loss of viability in buried seeds; and (5) ability to form persistent soil seed banks. Freshly matured seeds exhibited conditional physiological dormancy, with germination at high temperatures (32/18 °C) but not at low and cold ones (5, 15/4, 20/7 °C). The germination ability increased with time of dry storage and with GA3, thereby suggesting nondeep physiological dormancy. Under outdoor conditions, no seedlings emerged during the first post-sown autumn, but emergence peaks occurred in late winter–early spring. Both species could form small persistent soil seed banks with short durations (3–5 years). A plant production protocol from seeds was established for both taxa. [ABSTRACT FROM AUTHOR]

Members of the genus Atropa contain various tropane alkaloids, including atropine ((±)-hyoscyamine) and scopolamine, which possess medicinal properties. Preserving the diverse genetic background of wild populations via optimal plant production from seeds could be essential for avoiding the loss of potential uses. We analyzed the germination ecology of two Atropa species comprising the threatened A. baetica and widespread A. belladonna to determine the: (1) influence of temperature, light, and seed age on germination patterns; (2) effects of cold stratification and gibberellic acid (GA3); (3) phenology of seedling emergence in outdoor conditions; (4) phenology of dormancy break and loss of viability in buried seeds; and (5) ability to form persistent soil seed banks. Freshly matured seeds exhibited conditional physiological dormancy, with germination at high temperatures (32/18 °C) but not at low and cold ones (5, 15/4, 20/7 °C). The germination ability increased with time of dry storage and with GA3, thereby suggesting nondeep physiological dormancy. Under outdoor conditions, no seedlings emerged during the first post-sown autumn, but emergence peaks occurred in late winter–early spring. Both species could form small persistent soil seed banks with short durations (3–5 years). A plant production protocol from seeds was established for both taxa.

* Premise of the study : Seed longevity and persistence in soil seed banks may be especially important for population persistence in ecosystems where opportunities for seedling establishment and disturbance are unpredictable. The fire regime, an important driver of population dynamics in sagebrush steppe ecosystems, has been altered by exotic annual grass invasion. Soil seed banks may play an active role in post? re recovery of the foundation shrub Artemisia tridentata, yet conditions under which seeds persist are largely unknown. * Methods : We investigated seed longevity of two Artemisia tridentata subspecies in situ by retrieving seed bags that were placed at varying depths over a 2 yr period. We also sampled naturally dispersed seeds in litter and soil immediately after seed dispersal and before flowering in subsequent seasons to estimate seed persistence. * Key results : After 24 mo, seeds buried at least 3 cm below the soil surface retained 30 - 40% viability whereas viability of seeds on the surface and under litter declined to 0 and < 11%, respectively. The density of naturally dispersed seeds in the seed bank was highly heterogeneous both spatially and temporally, and attrition varied significantly by region. * Conclusions : Our study suggests that Artemisia tridentata has the potential to form a short-term soil seed bank that persists longer than has been commonly assumed, and that burial is necessary for seed longevity. Use of seeding techniques that promote burial of some seeds to aid in formation of a soil seed bank may increase restoration potential. [ABSTRACT FROM AUTHOR]