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Magnoliaceae is a family of dicotyledonous plants with primitive flowers and is one of the oldest families of flowering plants. In this paper, the chloroplast genomes of 26 species of Magnoliaceae were contrasted and compared to help clarify the relationships among them. The size of the 26 Magnoliaceae chloroplast genomes ranged from 158177 bp to 160183 bp, and approximately 1298 simple-sequence repeats were detected. For long-repeat sequences, 197 repeat loci, including 144 forward repeats, 52 palindromic repeats, and 1 reverse repeat, were detected. In four species, an abnormal gene, rpl22, contained premature stop codons. Moreover, three noncoding regions (ccsA-ndhD, ndhD-psaC, and trnH-psbA) with a nucleotide diversity (Pi) value greater than 0.02 and six coding genes (ycf1, petL, matK, psbT, rps19, and ndhF) with a Pi value of no less than 0.008 were identified (this information is important in resolving relationships within the Magnolia genus). The maximum likelihood (ML) and Bayesian inference (BI) trees had the same topological structures, with high support rates among 20 species, i.e., excluding Magnolia dealbata, Magnolia pyramidata, Magnolia dandyi, Magnolia aromatica, Magnolia conifera, and Magnolia glaucifolia. On the whole, these data represent valuable resources for Magnoliaceae chloroplast genomics and will be useful in future phylogenetic studies.Key words: Magnoliaceae, chloroplast genome, comparative analysis, phylogenomics, sequence divergence.Les magnoliacees constituent une famille de plantes dicotyledones a fleurs primitives qui se situe parmi les plus anciennes familles de plantes a fleurs. Dans cette etude, les auteurs ont compare les genomes chloroplastiques de 26 especes de magnoliacees afin d'aider a clarifier leurs relations. La taille des 26 genomes chloroplastiques de magnoliacees variait de 158 177 a 160 183 pb, et approximativement 1298 motifs de sequence repetee simple ont ete detectes. Pour les sequences repetees longues, 197 loci incluant 144 repetitions directes, 52 repetitions palindromiques et une repetition inversee ont ete detectes. Chez quatre especes, un gene anormal, rpl22, contenait des codons stop prematures. De plus, trois regions non codantes (ccsA-ndhD, ndhD-psaC et trnH-psbA) avaient une valeur de diversite nucleotidique (Pi) plus grande que 0,02, et six genes codants (ycfl, petL, matK, psbT, rps19 et ndhF) ont ete identifies avec une valeur de Pi de 0,008 et plus; cette information est importante pour demeler les relations a l'interieur du genre Magnolia. Les arbres phylogenetiques maximum de vraisemblance (ML) et inference bayesienne (BI) presentaient les memes topologies avec de forts taux de support parmi 20 especes, c.-a-d. excluant Magnolia dealbata, Magnolia pyramidata, Magnolia dandyi, Magnolia aromatica, Magnolia conifera et Magnolia glaucifolia. Dans l'ensemble, ces donnees constituent des ressources precieuses pour la genomique chloroplastique des magnoliacees et elles seront utiles pour des etudes phylogenetiques futures. [Traduit par la Redaction]Mots-cles: magnoliacees, genome chloroplastique, analyse comparative, phylogenomique, divergence de sequence., 1. IntroductionMagnoliaceae is recognized as one of the most primitive groups in angiosperms, and this family is of great significance for the study of the origin and phylogeny of flowering [...]

Camptotheac acuminata Decne is a unique tree species in China with an important secondary metabolite, camptothecin (CPT), used in the treatment of cancer. Nitrogen (N) is an important element that affects plant growth and the accumulation of CPT. Reports on the effect of N on CPT synthesis from a genetic perspective are scarce. To explore the effects of different N sources and levels on CPT synthesis in C. acuminata, two-year-old seedlings were fertilized with different concentrations of pure ammonium sulphate, source of ammonium N (NH4+–N), and potassium nitrate for nitrate N (NO3−–N). Concentrations of 2.5, 5, 7.5, and 10 g pot−1 NH4+–N and NO3−–N were used. The results showed that 7.5 g NH4+–N and NO3−–N treatments were best for growth and fresh weight of leaves. Compared with the other treatments, the CPT content, tryptophan synthase and tryptophan decarboxylase activities, and expression of the CaTSB and CaTDC1 genes under the 2.5 g NH4+–N and NO3−–N treatments peaked significantly at 30 days. However, the expression of CaTDC2 surpassed that of the other two genes at 60 days. Therefore, compared with NH4+–N source, the NO3−–N source was more beneficial for growth, and NO3−–N was better for CPT yield. Consequently, leaves of C. acuminata treated with 2.5 g NO3−–N could be harvested after 30 days to obtain maximum CPT content. CaTDC1 is more closely linked to CPT synthesis. The results of this study improved the production of CPT in C. acuminata via fertilization. [ABSTRACT FROM AUTHOR]

The article discusses the impact of globalization on economic and social development of the U.S. as well as issues associated with rising populism. Topics discussed include new trends in American Populism, rise of left-wing and right-wing populism, landmark policy positions taken by U.S. President Donald Trump to strengthen immigration policy and reshaping the international trade order.

Background: Clematis is the biggest genus in the family Ranunculaceae with about 300 species. Clematis is also a globally important commercial group of flowers, especially in the United States and European countries. Their petals with different colors and shapes make the genus the "Queen of the Vines". However, the genomic information and phylogeny of Clematis based on existing molecular studies are limited. In this paper, new microsatellites (SSR) markers were identified from the transcriptome data of C. finetiana obtained using the Illumina paired-end sequencing technology. Results: Sequences on a total of 71,900 high-quality unigenes with the mean length of 865 bp were produced in this study. There were 6192unigenes annotated and classified into 49 functional sub-groups in three main ontology categories in GO (Gen Ontology) database,14,022 unigenes mapped to COGs (Clusters of Orthologous Groups) database and classified into 25 functional categories, and 21,494 unigenes obtained and divided into 128 pathways of KEGG (Kyoto Encyclopedia of Genes) Database. A total of 7532 SSRs were discovered from 6337 unigenes. We randomly tested 210 primer pairs, of which 52 primer pairs were able to generate specific products, and 19 possessed polymorphism in the 13 wild populations of six species from Clematis, which were used as a test material. Conclusions: The dataset of C. finetiana transcriptome and the identified new SSR markers will promote genetic research and breeding effort in Clematis. [ABSTRACT FROM AUTHOR]