Avena fatua is an economically detrimental weed found in cereal growing areas worldwide. Knowledge about the variation of dormancy and germination characteristics, as well as of the genetic diversity and structure can provide additional information about different populations within a region. Identification and development of potential indicators or markers of seed germination behavior, would be useful for modelling emergence and seed bank dynamics. This study aimed to describe the initial germination, dormancy, and morphological characteristics of seeds from different Latvian populations of A. fatua and to investigate the genetic structure of local populations. Seed samples from 26 to 41 locations in different regions of Latvia were collected over three years. Seed morphology, initial germination, and the effect of dormancy-breaking treatments were determined. Seeds from 18 Latvian populations with contrasting seed dormancy characteristics were genotyped. Although morphological differences between seeds from different regions were revealed, genetic analysis of the selected populations indicated that the population structure was not related to geographical location, which probably reflects the impact of anthropogenic dispersal of A. fatua seeds. The effect of dormancy-breaking treatments varied between years, between climatic zones and between populations, indicating environmental influences as well as inherited dormancy.

Saussurea esthonica is an endangered plant species typical for wet inland habitats such as calcareous fens. Due to its limited population size and distribution, non-invasive sampling of is important in the research of S. esthonica. The aim of the present study was to assess the effect of mineral nutrient availability and substrate moisture on the growth, physiological status, and mineral nutrition of S. esthonica. The non-destructive measurement of physiological parameters was performed in native habitats during three vegetative seasons, followed by two experiments in controlled conditions. Soil at the two Estonian sites had a relatively larger similarity in the composition of plant-available mineral nutrients in comparison to the two Latvian sites. The chlorophyll a fluorescence parameter Performance Index correlated with the total precipitation in the respective month before measurement, but no significant relationship with other environmental variables was found. For mineral nutrient experiments, plants were grown in four substrates with different mineral nutrient composition, resembling that of soil at different S. esthonica sites. Plant growth and physiological indices were significantly affected by the mineral composition of the substrate. Differences in leaf and root mineral nutrient concentrations of S. esthonica plants in part reflected differences in substrate mineral concentration. To evaluate the effect of soil moisture on growth and photosynthesis-associated parameters of S. esthonica, plants were cultivated in “Pope+” substrate at four different moisture treatments (dry, normal, wet, and waterlodged). The most intense growth of S. esthonica plants was evident in waterlodged conditions, which decreased with a decrease in soil moisture. The biomass of leaves increased by 106% and that of the roots increased by 72% as soil moisture increased from dry to normal. For waterlodged plants, leaf biomass increased by 263% and root biomass increased by 566%, in comparison to that for plants cultivated in dry substrate. Substrate drying had a more negative effect on the growth of S. esthonica plants in comparison to that of waterlodging, and this can be directly linked to prevalent hydrological conditions of an alkaline fen habitat native to the species. Therefore, the preservation of the natural water regime in natural habitats is critical to the conservation of the species.

Societal Impact Statement: Ambitious targets have been set to backup seeds of threatened plants by the global strategy for plant conservation (GSPC), but it is unclear in how far these targets have been met and how seed collection should be organized to meet future challenges. Here, we provide an overview of the status of 44 countries in achieving seed conservation targets. We show that progress varies strongly across countries, but in general, targets of the 2011–2020 GSCP have not been reached. By a regional example, we illustrate how seed collection could be organized to safeguard our threatened flora. Summary: Seed banking of wild plants is a central pillar of conservation strategies for threatened plants. Target 8 of the Global Strategy for Plant Conservation (GSPC) called for at least 75% of threatened plant species to be conserved ex situ by 2020, but to what extent countries have achieved this target is unclear. Consequently, it is unknown how seed banking should be organized in future to safeguard plant diversity and support the increasing demand for seeds for habitat restoration. We conducted a comprehensive survey across 44 countries in Europe and western Asia and collected information on seed bank stocks of native taxa. We harmonized the taxonomic names across the collections and matched them against a database of national plant Red Lists to assign each taxon its IUCN (International Union for Conservation of Nature) threat status in its country of origin. We analysed each country's achievement in terms of the conservation of its threatened flora and evaluated the quality of the collections in terms of genetic representativeness and seed quantity. We found that none of the studied countries had reached Target 8 of the GSPC by 2020. While a few countries had come close to it, on average only 21% of threatened taxa were conserved across countries. Our results demonstrate that the current seed conservation strategy has not met conservation demands. Using an example from Belgium, where considerable progress has been achieved by investing in a network of volunteer seed collectors, we show how future seed collection could be organized in collaborative community‐based approaches.