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To understand how the environment drives spatial variation in population dynamics, we need to assess the effects of a large number of potential drivers on vital rates (survival, growth, and reproduction) and explore these relationships over large geographical areas and broad environmental gradients. In this study, we examined the effects of a wide variety of abiotic and biotic environmental factors on the demography of the forest understory herb Actaea spicata between 2017 and 2019 at 40 sites across Sweden, including the northern range margin of its distribution. We assessed the effects of potential environmental drivers on vital rates using generalized linear mixed models (GLMMs) and then quantified the impact of each important driver on population growth rate (λ) using integral projection models (IPMs). Population dynamics of A. spicata were mostly driven by environmental factors affecting survival and growth, such as air humidity, soil depth, and forest tree species composition, and thus, those drivers jointly determined the realized niche of the species. Soil pH had a strong effect on the flowering probability, while the effect on λ was relatively small. In addition to identifying specific drivers for A. spicata's population dynamics, our study illustrates the impact that spatial variation in environmental conditions can have on λ. Assessing the effects of a broad range of potential drivers, as done in this study, is important not only to quantify the relative importance of different drivers for population dynamics but also to understand species distributions and abundance patterns. [ABSTRACT FROM AUTHOR]

In animals, age-associated disorders are believed to be connected to shifts in the antioxidant/pro-oxidant balance in favour of oxidative stress. However, the contribution of oxidative stress to ageing in long-lived perennials has not been explored to date., Here, we tested age- and sex-related changes in several photo-oxidative stress markers in Borderea pyrenaica, a small dioecious geophyte relict of the Tertiary with one of the longest life spans ever recorded for a non-clonal herb (more than 300 years). Given that survival increases with age in B. pyrenaica, we hypothesized that oxidative stress does not increase with ageing because the species develops improved anti-oxidant defence., In three field samplings performed during 2008, 2010 and 2011 in the Central Pyrenees ( NE Spain), we examined the effects of ageing and sex on photosynthetic pigment levels, PSII integrity ( F v /F m ratio), lipid peroxidation, and the extent of photo and anti-oxidant protection in chloroplasts. Furthermore, we explored whether age and sex affect plant response to severe natural desiccation., Both male and female plants maintained chlorophyll levels intact, as well as the F v/ F m ratio and the levels of lipid peroxidation, irrespective of age. This finding suggests the absence of age-associated oxidative stress at the organismal level. Furthermore, photoprotection mechanisms were found to be similarly efficient in the oldest individuals as in juvenile plants, in terms of xanthophyll cycle de-epoxidation and accumulation of low-molecular-weight antioxidants (carotenoids and tocopherols). Indeed, females over 100 years of age were the most resistant to severe desiccation, maintaining higher leaf hydration levels, less chlorophyll degradation and better PSII integrity under stress than females below 100 years, males below or above 100 years, and juveniles., Synthesis. Neither males nor females of the extraordinarily long-lived B. pyrenaica show age-dependent signs of oxidative stress. This observation suggests that age-induced oxidative stress is not a universal feature of ageing in perennial plants. Indeed, females older than 100 years showed signs of negative senescence, in that they registered improved physiological performance with increasing age. [ABSTRACT FROM AUTHOR]

* Premise of the study: Using genomic shotgun 454 sequencing, 50 candidate microsatellite markers were targeted for the arctic--alpine polyploid perennial herb Bistorta vivipara to distinguish between individual genets and ramets within a population. * Methods and Results: Out of the 50 markers, 31 were polymorphic for seven test samples. We have developed a multiplex protocol for 16 of these microsatellite markers. * Conclusions: Our results show that the microsatellite markers provide a powerful tool for the research on genetic variation of B. vivipara. [ABSTRACT FROM AUTHOR]

Negative effects of habitat fragmentation on individual performance have been widely documented, but relatively little is known about how simultaneous effects on multiple vital rates translate into effects on population viability in long-lived species. In this study, we examined relationships between population size, individual growth, survival and reproduction, and population growth rate in the perennial plant Phyteuma spicatum. Population size positively affected the growth of seedlings, the survival of juveniles, the proportion of adults flowering, and potential seed production. Analyses with integral projection models, however, showed no relationship between population size and population, growth rate. This was due to the fact that herbivores and pathogens eliminated the relationship between population size and seed production, and that population growth rate was not sensitive to changes in the vital rates that varied with population size. We conclude that effects of population size on vital rates must not translate into effects on population growth rate, and that populations of long-lived -organisms may partly be able to buffer negative effects of small population size on vital rates that have a relatively small influence on population growth rate. Our study illustrates that we need to be cautious when assessing the consequences of habitat fragmentation for population viability based on effects on only one or a few vital rates. [ABSTRACT FROM AUTHOR]

• Premise of the study: Microsatellite primers were developed in Iris ensata (Iridaceae) to provide polymorphic markers for further studies into population genetics. • Methods and Results: Thirteen polymorphic microsatellite loci were isolated from I. ensata. These loci were successfully amplified in two natural populations of I. ensata from eastern China (Longwangshan, Zhejiang Province) and northeastern China (Jinchuan, Jilin Province). There was no significant linkage disequilibrium found for any pair of loci. These loci contained between two and 12 alleles per locus across all 48 individuals of I. ensata. The number of alleles per locus varied from two to 10 at the population level and the observed and expected heterozygosities ranged from 0.167 to 0.958 and from 0.284 to 0.853, respectively. • Conclusions: These loci showed high levels of polymorphism and could be used to study the population genetic structure, genetic relationships, and phylogeography of I. ensata. [ABSTRACT FROM AUTHOR]

We developed eight polymorphic microsatellite simple sequence repeat (SSR) loci from genomic DNA of a clonal perennial herb, Convallaria keiskei, using a dual-suppression-polymerase chain reaction (PCR) technique and an improved technique. These markers with four to 10 alleles per locus identified 29 genotypes in 82 samples collected from a population in Hokkaido, Japan. The observed and expected heterozygosities ranged from 0.241 to 0.862 and from 0.639 to 0.825, respectively. These SSR markers will be available to identify genets and evaluate genetic diversity of C. keiskei. [ABSTRACT FROM AUTHOR]

Premise: Polymorphic microsatellite markers were developed as a tool for genetic investigations of Filipendula vulgaris (Rosaceae) and related species. Methods and Results: Seventeen new polymorphic microsatellite markers were developed for F. vulgaris using the Illumina MiSeq platform. Polymorphism of the 17 loci was tested in three populations. We identified a total of 203 alleles, ranging from four to 19 per locus, with levels of observed and expected heterozygosity ranging from 0.267 to 1.000 and 0.461 to 0.899, respectively. Primers were also tested for cross‐amplification in three related species. Seven loci successfully cross‐amplified in F. camtschatica and F. ulmaria, whereas we detected positive cross‐amplification in only three loci in Geum urbanum. Conclusions: The newly developed microsatellite primers will serve as useful genetic tools for further population genetic studies on F. vulgaris and related species. [ABSTRACT FROM AUTHOR]

Premise: Microsatellite markers were developed in the federally endangered species Liatris helleri (Asteraceae) to evaluate species boundaries with closely related congeners within the genus. Methods and Results: Using Illumina data, 17 primer pairs were developed in populations of L. helleri. The primers amplified motifs from tri‐ to hexanucleotide repeats with one to 17 alleles per locus. Primers were also tested for cross‐amplification in L. aspera, L. microcephala, and L. pycnostachya. Conclusions: The developed primers for L. helleri serve as a novel genetic tool for future investigations in this genus, allowing for more explicit species delineation as well as population genetic analyses. [ABSTRACT FROM AUTHOR]