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Influência do ambiente de armazenamento na qualidade fisiológica de sementes de milheto (Pennisetum glaucum (L.) R. Br
Silva, Girlânio Holanda da; Toledo, Mariana Zampar ; Teixeira, Renake Nogueira ; Rossi, Rubiana Falopa ; Nakagawa, João - \ 2019
Journal of seed science 41 (2019)3. - ISSN 2317-1537 - p. 286 - 292.
Conservation - Germination - Physiological quality
Millet is a species of the grass family used in cattle pastures, for hay, for silage, and in soil cover in no-tillage systems. However, studies on seed production and post-harvest techniques for this species have not been sufficiently developed, considering the demand for and potential of this crop. The objective of this study was to monitor the physiological quality of millet seeds stored in porous packaging. Millet seeds were stored under four ambient conditions (natural laboratory environment, dry chamber, refrigerator, and freezer). Physiological quality was evaluated by germination and vigor tests before and during storage each year, up to six years for the dry chamber and natural laboratory environment, and up to 12 years for the refrigerator and freezer. Analysis of variance was conducted on the data, which were in 4 × 6 and 2 × 12 (environment and storage period) factorial arrangements. The means of the environments were compared by the Tukey test (p ≤ 0.05) and the storage periods by regression analysis. The germination capacity of millet seeds is best conserved in a refrigerator and freezer, and they remain viable for up to twelve years of storage under these conditions.
Root architecture system of oilseed species from the Jatropha genus during seed development and germination
Brito, Cristiane D. de; Loureiro, Marta B. ; Ribeiro, Paulo R. ; Vasconcelos, Paulo Carvalho T. ; Moreno, Maria Lúcia V. ; Fernandez, Luzimar G. ; Hilhorst, Henk W.M. ; Lammeren, Andre van; Ligterink, Wilco ; Castro, Renato D. de - \ 2019
Industrial Crops and Products 139 (2019). - ISSN 0926-6690
Germination - Guard cells - Root development - Seed embryo
The life cycle of a seed plant involves subsequent stages of development including germination and seedling establishment. Morphological structures have a fundamental role in these phases, since they are strongly related to physiological adaptations to survival in a range of environments. The present study describes an important morphophysiological and anatomical pattern in embryos of Jatropha genus, involving adaptations for germination and seedling growth. Seed embryos of Jatropha curcas, J. gossypiifolia, J. podagrica and J. multifida were examined using different physiological and microscopic assays. Jatropha species present a multimeristematic embryo composed of one main apical primary meristem plus four radial primary meristems. Seed germination is completed by simultaneous protrusion of five functional roots and seedlings are able to survive even with only one of them. The hypocotyl-radicle transition zone exhibiting different stomata sizes, ontogenic phases and short lifespan limited to the germination. Stomata fractures at mid-region due to the fact that guard cells were not lengthen as neighboring epidermal cells, forming a large cavity in the epidermal tissue during seedling growth. The results showed an unusual and complex root structure for the Jatropha genus. The presence of stomata operating strictly during seed germination could be associated to intense energetic metabolism demanded for the simultaneous growth of the five roots originated from the multimeristematic radicle. This study provides important insights into the understanding of seed germination of Jatropha species in response to stress environmental conditions.
Editorial: Actinobacteria, a source of biocatalytic tools
Tischler, Dirk ; Berkel, Willem J.H. Van; Fraaije, Marco W. - \ 2019
Frontiers in Microbiology 10 (2019). - ISSN 1664-302X
Actinomycetes - Biocatalysis - Biotechnology - Extremophile actinobacteria - Germination - High GC genetics - Novel biocatalysts - Secondary metabolites
Heat resistance of spores of 18 strains of Geobacillus stearothermophilus and impact of culturing conditions
Wells-Bennik, Marjon H.J. ; Janssen, Patrick W.M. ; Klaus, Verena ; Yang, Chi ; Zwietering, Marcel H. ; Besten, Heidy M.W. Den - \ 2019
International Journal of Food Microbiology 291 (2019). - ISSN 0168-1605 - p. 161 - 172.
Enumeration - Germination - Inactivation - Modelling - Sporulation - Variability
In this study, different methods were evaluated for enumeration of spores of G. stearothermophilus, different sporulation methods were assessed for yields and wet heat resistances of obtained spores, and subsequently, the variation in heat resistances of spores was determined. Overall, tryptone soya agar (TSA) was the most suitable medium for enumeration of spores of this thermophilic bacterium. Sporulation on different media both at 55 and at 61 °C led to considerable variation in spore heat resistance. The heat resistance of spores was highest upon sporulation on medium supplemented with free ions of calcium, potassium, magnesium and manganese (CaKMgMn). For 18 different G. stearothermophilus strains that were isolated from various sources, spores were subsequently produced on nutrient agar supplemented with CaKMgMn at 55 °C. Strain ATCC 12980T, also known as 9A20, which is commonly used in steam sterilization tests was included. The survival of spores of all strains was assessed at 125 °C and 130 °C using two independent spore batches per strain. The mean D125°C for spores of the 18 strains was 1.1 min (95% PI 0.48–2.3 min) and the mean D130°C was 0.37 min (95% PI 0.17–0.82 min). For spore inactivation of these 18 strains, a z-value of 11.1 °C was estimated, resulting in an estimated D-value of 2.4 min (95% PI 1.1–5.2) at the reference temperature 121.1 °C. Based on the data sets obtained in this study, it was found that the variability in spore heat resistance could largely be attributed to strain variability and conditions used during sporulation (especially the sporulation medium); reproduction and experimental variabilities were much smaller. The established variabilities were compared with the overall variability in spore heat resistance of G. stearothermophilus based on a meta-analysis of reported D-values. The data presented indicate that strain variability and history of sporulation each account for approximately half of the overall variability observed with respect to the heat resistance of spores of G. stearothermophilus. The findings presented in this study allow for optimal recovery of G. stearothermophilus spores from foods and a better understanding of factors that determine the heat resistance properties of spores of G. stearothermophilus. Moreover, this study once more underlines the limited effects of heat treatments used in the food industry on inactivation of spores of this bacterium.
Mass spectrometric characterisation of avenanthramides and enhancing their production by germination of oat (Avena sativa)
Bruijn, Wouter J.C. de; Dinteren, Sarah van; Gruppen, Harry ; Vincken, Jean Paul - \ 2019
Food Chemistry 277 (2019). - ISSN 0308-8146 - p. 682 - 690.
Avena sativa - Avenanthramides - Cereal grain - Germination - LC-MS - Phytoalexin - Plant defence - Poaceae
Avenanthramides are amides, with a phenylalkenoic acid (PA) and an anthranilic acid (AA) subunit, which are secondary metabolites of oat. Oat seeds were germinated, extracted, and the avenanthramides analysed by a combination of UHPLC with ion trap and high resolution ESI-MS. Typical fragmentation pathways with corresponding diagnostic fragments belonging to the PA and AA subunits were identified and summarised in a decision guideline. Based on these findings 28 unique avenanthramides were annotated in the oat seed(ling) extracts, including the new avenanthramide 6f (with a 4/5-methoxy AA subunit). Avenanthramide content increased by 25 times from seed to seedling. Avenanthramides 2p, 2c, and 2f, which are commonly described as the major avenanthramides, represented less than 20% of the total content in the seedlings. Future quantitative analyses should, therefore, include a wider range of avenanthramides to avoid underestimation of the total avenanthramide content.
Quantifying establishment limitations during the ecological restoration of species-rich Nardus grassland
Daele, Frederik Van; Wasof, Safaa ; Demey, Andreas ; Schelfhout, Stephanie ; Schrijver, A. De; Baeten, Lander ; Ruijven, Jasper van; Mertens, Jan ; Verheyen, Kris - \ 2017
Applied Vegetation Science 20 (2017)4. - ISSN 1402-2001 - p. 594 - 607.
Community assembly - Establishment limitation - Germination - Intraspecific trait variation - Plant–soil interactions - Restoration ecology - Semi-natural Nardus grasslands
Aims: Successful establishment of species-rich Nardus grasslands on ex-agricultural land requires identification and removal of barriers to effective seed germination and seedling survival. Therefore, we investigate how germination and early development are affected by soil conditions from different restoration phases and how this relates to their specific plant strategies. Location: Grasslands and experiments in northern Belgium. Methods: We selected three grassland restoration phases (Lolium perenne grasslands, grass–herb mix grasslands and species-rich Nardus grasslands), which were characterized by a distinct plant community and soils with contrasting abiotic and biotic properties (respectively, eutrophic, mesotrophic and oligotrophic soils). In a first germination experiment we investigated the species-specific responses (germination, lag time and emergence rate) of 70 grassland species (that typically occur along the restoration gradient) in each of the selected soils. Second, a mesocosm experiment was set-up in which a mixture of 19 species (representative of the distinct grassland restoration phases) was grown together in the respective soils. Here, we analysed the intraspecific variation of plant growth, SLA and identified changes in community assembly. Results: Irrespective of soil influences, Nardus grassland species had significantly lower germination potentials and longer germination lag times than L. perenne grassland species. Germination (and its lag time) of grass–herb mix grassland species were negatively affected by the oligotrophic soils. Soil factors determined early growth patterns during the emergence and establishment phase. L. perenne grassland species exhibited a more plastic growth response and were highly dependent on soil type. Nardus grassland species exhibited large intraspecific variation in SLA, which was found to be significantly lower in the oligotrophic soils. Even though the difference in bio-available P between mesotrophic and oligotrophic soils was minor, Nardus grassland species were only able to compete in the oligotrophic soils (no significant difference in biomass between communities). Mesotrophic mesocosms exhibited the highest species richness after 200 d of growth. Conclusion: Plant species from the three grassland restoration phases display distinct germination strategies, irrespective of soil type. Interactions between growth strategies and soil factors determine competitive asymmetry and therefore shape community assembly in the distinct grassland phases.
Analysis of germination capacity and germinant receptor (sub)clusters of genomesequenced Bacillus cereus environmental isolates and model strains
Warda, Alicja K. ; Xiao, Yinghua ; Boekhorst, Jos ; Wells-Bennik, Marjon H.J. ; Nierop Groot, Masja N. ; Abee, Tjakko - \ 2017
Applied and Environmental Microbiology 83 (2017)4. - ISSN 0099-2240
Bacillus cereus - Germination - Sporeformer - Spores
Spore germination of 17 Bacillus cereus food isolates and reference strains was evaluated using flow cytometry analysis in combination with fluorescent staining at a single-spore level. This approach allowed for rapid collection of germination data under more than 20 conditions, including heat activation of spores, germination in complex media (brain heart infusion [BHI] and tryptone soy broth [TSB]), and exposure to saturating concentrations of single amino acids and the combination of alanine and inosine. Whole-genome sequence comparison revealed a total of 11 clusters of operons encoding germinant receptors (GRs): GerK, GerI, and GerL were present in all strains, whereas GerR, GerS, GerG, GerQ, GerX, GerF, GerW, and GerZ (sub)clusters showed a more diverse presence/absence in different strains. The spores of tested strains displayed high diversity with regard to their sensitivity and responsiveness to selected germinants and heat activation. The two laboratory strains, B. cereus ATCC 14579 and ATCC 10987, and 11 food isolates showed a good germination response under a range of conditions, whereas four other strains (B. cereus B4085, B4086, B4116, and B4153) belonging to phylogenetic group IIIA showed a very weak germination response even in BHI and TSB media. Germination responses could not be linked to specific (combinations of) GRs, but it was noted that the four group IIIA strains contained pseudogenes or variants of subunit C in their gerL cluster. Additionally, two of those strains (B4086 and B4153) carried pseudogenes in the gerK and gerRI (sub)clusters that possibly affected the functionality of these GRs.
Extensive translational regulation during seed germination revealed by polysomal profiling
Bai, Bing ; Peviani, Alessia ; Horst, Sjors van der; Gamm, Magdalena ; Snel, Berend ; Bentsink, Leónie ; Hanson, Johannes - \ 2017
New Phytologist 214 (2017)1. - ISSN 0028-646X - p. 233 - 244.
Arabidopsis - Germination - Imbibition - Polysomal profiling - Ribosome - RNA structure - Seedling establishment - Translatomics
This work investigates the extent of translational regulation during seed germination. The polysome occupancy of each gene is determined by genome-wide profiling of total mRNA and polysome-associated mRNA. This reveals extensive translational regulation during Arabidopsis thaliana seed germination. The polysome occupancy of thousands of individual mRNAs changes to a large extent during the germination process. Intriguingly, these changes are restricted to two temporal phases (shifts) during germination, seed hydration and germination. Sequence features, such as upstream open reading frame number, transcript length, mRNA stability, secondary structures, and the presence and location of specific motifs correlated with this translational regulation. These features differed significantly between the two shifts, indicating that independent mechanisms regulate translation during seed germination. This study reveals substantial translational dynamics during seed germination and identifies development-dependent sequence features and cis elements that correlate with the translation control, uncovering a novel and important layer of gene regulation during seed germination.
High-throughput scoring of seed germination
Ligterink, Wilco ; Hilhorst, Henk W.M. - \ 2017
In: Methods in Molecular Biology / Kleine-Vehn, Jürgen, Sauer, Michael, Humana Press Inc. (Methods in Molecular Biology ) - ISBN 9781493964673 - p. 57 - 72.
Arabidopsis thaliana - Automatic scoring - Curve-fitting - Germination - High-throughput analysis - Image analysis
High-throughput analysis of seed germination for phenotyping large genetic populations or mutant collections is very labor intensive and would highly benefit from an automated setup. Although very often used, the total germination percentage after a nominated period of time is not very informative as it lacks information about start, rate, and uniformity of germination, which are highly indicative of such traits as dormancy, stress tolerance, and seed longevity. The calculation of cumulative germination curves requires information about germination percentage at various time points. We developed the GERMINATOR package: a simple, highly cost-efficient, and flexible procedure for high-throughput automatic scoring and evaluation of germination that can be implemented without the use of complex robotics. The GERMINATOR package contains three modules: (I) design of experimental setup with various options to replicate and randomize samples; (II) automatic scoring of germination based on the color contrast between the protruding radicle and seed coat on a single image; and (III) curve fitting of cumulative germination data and the extraction, recap, and visualization of the various germination parameters. GERMINATOR is a freely available package that allows the monitoring and analysis of several thousands of germination tests, several times a day by a single person.
Effects of temperature, moisture and soil type on seedling emergence and mortality of riparian plant species
Heerdt, Gerard N.J. ter; Veen, Ciska G.F. ; Putten, Wim H. van der; Bakker, Jan P. - \ 2017
Aquatic Botany 136 (2017). - ISSN 0304-3770 - p. 82 - 94.
Chenopodium rubrum - Drawdown - Functional groups - Germination - Moisture - Mortality - Phragmites australis - Riparian plant species - Rumex maritimus - Seedling emergence - Senecio congestus - Soil type - Temperature - Typha latifolia
Restoration of riparian plant communities on bare soil requires germination of seeds and establishment of seedlings. However, species that are present in the soil seed bank do not always establish in the vegetation. Temperature, moisture conditions and soil type could play a major role in the establishment of riparian plant communities, through impacting seedling emergence. We studied the effects of temperature, combinations of temperature and moisture conditions, and soil type on seedling emergence and mortality of perennial reeds (Typha latifolia and Phragmites australis) and annual or biannual pioneer species (Senecio congestus, Rumex maritimus and Chenopodium rubrum). The responses to the environmental conditions were species-specific and resulted in context-dependent differences in proportions of species emerging from the soil seed bank. Typha latifolia and S. congestus preferred wet or very wet conditions, C. rubrum and R. maritimus preferred dry to very dry conditions. Phragmites australis was able to establish under all conditions. Both cold and very dry conditions resulted in low emergence and survival, which was not fully compensated for when conditions became favorable again. Senecio congestus, R. maritimus and C. rubrum benefitted from secondary seedling emergence when, after a very dry period, the weather became very wet again, while T. latifolia and P. australis remained absent. When the conditions remained wet, more seedlings emerged from sand than from clay. However, when the soil was drying out, fewer seedlings emerged from sand than from clay. We propose that using information on plant species-specific responses to abiotic environmental conditions during germination, emergence and establishment can help to restore different target riparian plant communities.
Soil seed bank dynamics under the influence of grazing as alternative explanation for herbaceous vegetation transitions in semi-arid rangelands
Langevelde, Frank van; Tessema, Zewdu K. ; Boer, Fred de; Prins, Herbert H.T. - \ 2016
Ecological Modelling 337 (2016). - ISSN 0304-3800 - p. 253 - 261.
Annual grass - Bare soil - Germination - Grazing - Perennial grass - Seed longevity - State-and-transition models
Ecological studies have frequently stressed that the availability of seeds in the soil is important for the recovery of semi-arid rangelands. However, the crucial role of soil seed banks has not been incorporated into rangeland models to understand vegetation states and transitions in semi-arid rangelands. We developed and evaluated a novel model to show that the availability of seeds in the soil seed banks as a function of plant cover can trigger transitions from perennial to annual grasses and from annual grasses to bare soil with increasing grazing pressure. The model indicates that when grazing pressure is low, a high cover of perennial grasses and a large soil seed bank of these grasses may be present, whereas annual grasses with their seeds in the soil appear with increasing grazing. When grazing pressure further increases, vegetation cover and the soil seed bank size decline. We found that the positive feedback between plant cover and the size of the soil seed bank depends on seed traits, i.e., longevity and germination rate. This positive feedback is an alternative explanation for a sudden vegetation changes in rangelands, which are often explained by the positive feedback between plant cover and the infiltration rate of rain into the soil. In contrast to this latter positive feedback, our model can explain shifts in vegetation from perennials to annuals and vice versa on different soil types, which are often seen in semi-arid rangelands. Our model contributes therefore to the understanding of vegetation dynamics for the proper management and possible restoration of degraded semi-arid rangelands.
Tolerância à dessecação e longevidade de sementes germinadas de Sesbania virgata (Cav.) Pers.
Costa, Maria Cecília Dias ; Faria, José Marcio Rocha ; José, Anderson Cleiton ; Ligterink, Wilco ; Hilhorst, Henk W.M. - \ 2016
Journal of seed science 38 (2016)1. - ISSN 2317-1537 - p. 50 - 56.
Desiccation tolerance - Germination - Osmotic stress - Storage
Seed desiccation tolerance (DT) and longevity are necessary for better dissemination of plant species and establishment of soil seed bank. They are acquired by orthodox seeds during the maturation phase of development and lost upon germination. DT can be re-induced in germinated seeds by an osmotic and/or abscisic acid treatment. However, there is no information on how these treatments affect seed longevity. Germinated Sesbania virgata seeds were used as a model system to investigate the effects of an osmotic treatment to re-establish DT on seed longevity. Longevity of germinated S. virgata seeds treated and non-treated by an osmoticum was analysed after storage or artificial ageing. The radicle is the most sensitive organ, the cotyledons are the most resistant, and the ability to produce lateral roots is the key for whole seed survival. Germinated S. virgata seeds with 1mm protruded radicle tolerate desiccation and storage for up to three months without significant losses in viability. An osmotic treatment can improve DT in these seeds, but not longevity. Germinated S. virgata seeds are a good model to study DT uncoupled from longevity. Further studies are necessary to unveil the molecular mechanisms involved in both DT and longevity.
Barley seed aging : Genetics behind the dry elevated pressure of oxygen aging and moist controlled deterioration
Nagel, Manuela ; Kodde, Jan ; Pistrick, Sibylle ; Mascher, Martin ; Börner, Andreas ; Groot, Steven P.C. - \ 2016
Frontiers in Plant Science 7 (2016). - ISSN 1664-462X
Caryopsis - Genotype - Germination - Linkage mapping - Seed conservation - Seed storage
Experimental seed aging approaches intend to mimic seed deterioration processes to achieve a storage interval reduction. Common methods apply higher seed moisture levels and temperatures. In contrast, the “elevated partial pressure of oxygen” (EPPO) approach treats dry seed stored at ambient temperatures with high oxygen pressure. To analyse the genetic background of seed longevity and the effects of seed aging under dry conditions, the EPPO approach was applied to the progeny of the Oregon Wolfe Barley (OWB) mapping population. In comparison to a non-treated control and a control high-pressure nitrogen treatment, EPPO stored seeds showed typical symptoms of aging with a significant reduction of normal seedlings, slower germination, and less total germination. Thereby, the parent Dom (“OWB-D”), carrying dominant alleles, is more sensitive to aging in comparison to the population mean and in most cases to the parent Rec (“OWB-R”), carrying recessive alleles. Quantitative trait locus (QTL) analyses using 2832 markers revealed 65 QTLs, including two major loci for seed vigor on 2H and 7H. QTLs for EPPO tolerance were detected on 3H, 4H, and 5H. An applied controlled deterioration (CD) treatment (aged at higher moisture level and temperature) revealed a tolerance QTL on 5H, indicating that the mechanism of seed deterioration differs in part between EPPO or CD conditions.
Bacterial Spores in Food : Survival, Emergence, and Outgrowth
Wells-Bennik, Marjon H.J. ; Eijlander, Robyn T. ; Besten, Heidy M.W. Den; Berendsen, Erwin M. ; Warda, Alicja K. ; Krawczyk, Antonina O. ; Nierop Groot, Masja N. ; Xiao, Yinghua ; Zwietering, Marcel H. ; Kuipers, Oscar P. ; Abee, Tjakko - \ 2016
Annual Review of Food Science and Technology 7 (2016). - ISSN 1941-1413 - p. 457 - 482.
Bacillus - Clostridium - Germination - Heat resistance - Predictive modeling - Spore dormancy
Spore-forming bacteria are ubiquitous in nature. The resistance properties of bacterial spores lie at the heart of their widespread occurrence in food ingredients and foods. The efficacy of inactivation by food-processing conditions is largely determined by the characteristics of the different types of spores, whereas food composition and storage conditions determine the eventual germination and outgrowth of surviving spores. Here, we review the current knowledge on variation in spore resistance, in germination, and in the outgrowth capacity of spores relevant to foods. This includes novel findings on key parameters in spore survival and outgrowth obtained by gene-trait matching approaches using genome-sequenced Bacillus spp. food isolates, which represent notorious food spoilage and pathogenic species. Additionally, the impact of strain diversity on heat inactivation of spores and the variability therein is discussed. Knowledge and quantification of factors that influence variability can be applied to improve predictive models, ultimately supporting effective control of spore-forming bacteria in foods.
Variation in accumulation of isoflavonoids in Phaseoleae seedlings elicited by Rhizopus
Aisyah, Siti ; Gruppen, Harry ; Andini, Silvia ; Bettonvil, Monique ; Severing, Eduard ; Vincken, Jean Paul - \ 2016
Food Chemistry 196 (2016). - ISSN 0308-8146 - p. 694 - 701.
Flavonoid - Germination - Mass spectrometry - Phylogenetic relationship - Phytoalexin - Prenylation
Seeds from seven species of tribe Phaseoleae, i.e. Phaseolus, Vigna, Lablab and Psophocarpus, were investigated for inducibility of isoflavonoids by germination with or without subsequent elicitation with Rhizopus oryzae. Germination alone poorly induced isoflavonoid production (in the range of 0.2-0.7 mg representative compound equivalents (RCE)/g DW), whereas application of Rhizopus onto the seedlings increased the isoflavonoid content considerably (in the range of 0.5-3.3 mg RCE/g DW). The inducibility of different isoflavonoid subclasses in seedlings with Rhizopus varied per species. Isoflavones and isoflavanones were mainly found in elicited seedlings of Phaseolus, Vigna and Lablab, whereas pterocarpans were mainly observed in those of Psophocarpus. Despite their phylogenetic relatedness, the seeds of various species within Phaseoleae appeared to respond differently towards elicitation by Rhizopus during germination. The kind of molecules induced followed the phylogenetic relationship of the various species, but their amounts induced during germination, alone or combined with elicitation, did not.
How do bryophytes govern generative recruitment of vascular plants?
Soudzilovskaia, Nadejda A. ; Graae, Bente J. ; Douma, Jacob C. ; Grau, Oriol ; Milbau, Ann ; Shevtsova, Anna ; Wolters, Loes ; Cornelissen, Johannes H.C. - \ 2011
New Phytologist 190 (2011)4. - ISSN 0028-646X - p. 1019 - 1031.
Allelopathy - Bryophyte - Generative recruitment - Germination - Moisture - Plant-plant interaction - Seedling - Temperature
Interactions between vascular plants and bryophytes determine plant community composition in many ecosystems. Yet, little is known about the importance of interspecific differences between bryophytes with respect to their effects on vascular plants. We compared the extent to which species-specific bryophyte effects on vascular plant generative recruitment depend on the following underlying mechanisms: allelopathy, mechanical obstruction, soil moisture and temperature control. We sowed 10 vascular plant species into monospecific mats of six chemically and structurally diverse bryophytes, and examined 1-yr seedling recruitment. Allelopathic effects were also assessed in a laboratory phyto-assay. Although all bryophytes suppressed vascular plant regeneration, there were significant differences between the bryophyte species. The lack of interactions indicated the absence of species-specific adaptations of vascular plants for recruitment in bryophyte mats. Differences between bryophyte species were best explained by alterations in temperature regime under bryophyte mats, mostly by reduced temperature amplitudes during germination. The temperature regime under bryophyte mats was well predicted by species-specific bryophyte cushion thickness. The fitness of established seedlings was not affected by the presence of bryophytes. Our results suggest that climatically or anthropogenically driven changes in the species' composition of bryophyte communities have knock-on effects on vascular plant populations via generative reproduction.