Development of microsatellite markers for sister species Linum suffruticosum and Linum tenuifolium in their overlapping ranges

Background: Microsatellite markers were developed for distylous Linum suffruticosum and tested in the monomorphic sister species Linum tenuifolium. These species are perennial herbs endemic to the western and northwestern Mediterranean, respectively, with a partially overlapping distribution area. Methods and results: We developed 12 microsatellite markers for L. suffruticosum using next generation sequencing, and assessed their polymorphism and genetic diversity in 152 individuals from seven natural populations. The markers displayed high polymorphism, with two to 16 alleles per locus and population, and average observed and expected heterozygosities of 0.833 and 0.692, respectively. All loci amplified successfully in the sister species L. tenuifolium, and 150 individuals from seven populations were also screened. The polymorphism exhibited was high, with two to ten alleles per locus and population, and average observed and expected heterozygosities of 0.77 and 0.62, respectively. Conclusions: The microsatellite markers identified in L. suffruticosum and tested in L. tenuifolium are a powerful tool to facilitate future investigations of the population genetics, mating patterns and hybridization between both Linum species in their contact zone.European Research Council 757451Ministerio de Ciencia e Innovación CGL2013-45037-P, PGC2018 099608 B 100, PID2021-122715NB-I00European Union 89789

Adaptive divergence in resistance to herbivores in Datura stramonium

Defensive traits exhibited by plants vary widely across populations. Heritable phenotypic differentiation is likely to be produced by genetic drift and spatially restricted gene flow between populations. However, spatially variable selection exerted by herbivores may also give rise to differences among populations. To explore to what extent these factors promote the among-population differentiation of plant resistance of 13 populations of Datura stramonium, we compared the degree of phenotypic differentiation (PST) of leaf resistance traits (trichome density, atropine and scopolamine concentration) against neutral genetic differentiation (FST) at microsatellite loci. Results showed that phenotypic differentiation in defensive traits among-population is not consistent with divergence promoted by genetic drift and restricted gene flow alone. Phenotypic differentiation in scopolamine concentration was significantly higher than FST across the range of trait heritability values. In contrast, genetic differentiation in trichome density was different from FST only when heritability was very low. On the other hand, differentiation in atropine concentration differed from the neutral expectation when heritability was less than or equal to 0.3. In addition, we did not find a significant correlation between pair-wise neutral genetic distances and distances of phenotypic resistance traits. Our findings reinforce previous evidence that divergent natural selection exerted by herbivores has promoted the among-population phenotypic differentiation of defensive traits in D. stramonium

Present and future of ecological and evolutionary research in mediterranean-type ecosystems: Conclusions from the last international mediterranean ecosystems conference

Mediterranean‐type ecosystems (MTEs) have long attracted the attention of biologists worldwide. One of the main reasons is the tremendous vascular plant diversity within the five MTEs, including the Mediterranean Basin, southwestern and southern Australia, coastal and southern regions of California, central Chile and the Cape Region in South Africa. Mediterranean‐type ecosystems harbor almost 20%, i.e., about 50,000 species, of the world's known vascular plant species on less than 5% of the Earth's surface (Cowling et al., 1996). A combination of geological stability, climatic oscillations, fire frequency, and summer droughts created unique plant communities and floras with characteristic, unmistakable names, such as matorral, chaparral, maquis, fynbos and kwongan. Such a great interest in MTEs by the international scientific community was given concrete expression in 1971, when the International Society for Mediterranean Ecology (ISOMED) was established to promote research, conservation, and public awareness of the biological diversity of the world's Mediterranean‐type climate regions. Since then, the International Mediterranean Ecosystems Conference (MEDECOS) has periodically been held, rotating among Mediterranean‐type climate countries every 3–4 yr, to bring together scientists and natural resource managers with a strong interest in MTEs.We acknowledge the Severo Ochoa Program for Spanish Centers of Excellence in R+D+I (SEV‐2012‐0262) and the Vice‐Rectorate for Research of the University of Seville through operating grants for the conference

Precision measurement of the structure of the CMS inner tracking system using nuclear interactions

The structure of the CMS inner tracking system has been studied using nuclear interactions of hadrons striking its material. Data from proton-proton collisions at a center-of-mass energy of 13 TeV recorded in 2015 at the LHC are used to reconstruct millions of secondary vertices from these nuclear interactions. Precise positions of the beam pipe and the inner tracking system elements, such as the pixel detector support tube, and barrel pixel detector inner shield and support rails, are determined using these vertices. These measurements are important for detector simulations, detector upgrades, and to identify any changes in the positions of inactive elements