Pangenome inventory of Burkholderia sensu lato, Burkholderia sensu stricto, and the Burkholderia cepacia complex reveals the uniqueness of Burkholderia catarinensis.

Here the pangenome analysis of Burkholderia sensu lato (s.l.) was performed for the first time, together with an updated analysis of the pangenome of Burkholderia sensu stricto, and Burkholderia cepacia complex (Bcc) focusing on the Bcc B. catarinensis specific features of its re-sequenced genome. The pangenome of Burkholderia s.l., Burkholderia s.s., and of the Bcc was open, composed of more than 96% of accessory genes, and more than 62% of unknown genes. Functional annotations showed that secondary metabolism genes belonged to the variable portion of genomes, which might explain their production of several compounds with varied bioactivities. Taken together, this work showed the great variability and uniqueness of these genomes and revealed an underexplored unknown potential in poorly characterized genes. Regarding B. catarinensis 89T, its genome harbors genes related to hydrolases production and plant growth promotion. This draft genome will be valuable for further investigation of its biotechnological potentials.

Global rheophytes data set: angiosperms and gymnosperms.

The term rheophyte describes a biological group of flood-tolerant plants that are confined to the beds of swift-running streams and rivers in nature and grow up to flood level, but not beyond the reach of regularly occurring flash floods. Although over 35 yr have passed since the first global census of rheophytes, no updates have been recorded regarding the number of taxa in this biological group in seed plants. Therefore, the present work aimed to (1) review the main topics associated with rheophytism (e.g., morphological characteristics, genetic studies, geographic distribution, conservation, and evolutionary aspects); (2) provide an updated checklist of rheophytes distributed around the world considering the two main groups in seed plants (gymnosperms and angiosperms); (3) demonstrate the distribution of rheophytism in the angiosperm phylogeny; and (4) estimate the geographical distribution and richness of selected taxa on the world map for the first time. All data compiled for the present study originated from a search of peer-reviewed articles, secondary literature (theses, dissertations, reports, books, and floras), and electronic facilities. We compiled a data set composed of four taxa in gymnosperms (Podocarpaceae family) and 1,368 taxa (including obligate, facultative, and unclassified rheophytes) distributed in 114 families and 508 genera in angiosperms. Most of the studied taxa belong to eudicotyledons (72.81%), while 1.46% belong to magnoliids, and 25.73% belong to monocotyledons. The families with the highest number of taxa in descending order are Podostemaceae, Araceae, Myrtaceae, Rubiaceae, Asteraceae, Apocynaceae, Arecaceae, Fabaceae, Phyllanthaceae, and Poaceae. Of the 114 families plotted in angiosperm phylogeny, at least 80 harbor obligate rheophytes. The geographical distribution of rheophytes in angiosperms, as expected based on the first census of this biological group, is mainly in the tropical and subtropical regions. The high richness of rheophytic taxa was mostly found in southern Mexico, southern China, Borneo, and northern and eastern Australia. In contrast, the geographical distribution of rheophytes in gymnosperms is restricted to New Caledonia and Tasmania. The present study will help to advance knowledge regarding the diversity of rheophytes in angiosperms and gymnosperms while drawing attention to this biological group, which has often been overlooked. There are no copyright restrictions. Please cite this data paper when the data are used in publications and teaching events.

Checklist of climbing plants in an Araucaria forest of Rio Grande do Sul State, Brazil / Florística de trepadeiras em uma floresta de Araucária do Estado do Rio Grande do Sul, Brasil

Climbing plants are remarkable components of forests, highly contributing for the diversity and dynamics of communities. Studies focusing on climbing plants are scarce and for many vegetation types little is known about climbing species composition and their traits relevant for dispersal and establishment. The focus of this study is to provide the first floristic inventory of climbing plants in an Araucaria forest of Brazil, describing the dispersal syndromes and climbing mechanisms of species and comparing these traits and species composition patterns with other study sites in Southern Brazil. We found 104 taxa belonging to 33 families, with Asteraceae (22 spp.) and Apocynaceae (14 spp.) being the richest families. Among climbing mechanisms, stem twiner (50 spp.) is the most common, followed by tendril (20 spp.) and scrambler (12 spp.), while in relation to the dispersal syndromes, anemochoric species (65 spp.) are the most relevant followed by endozoochoric (28 spp.). Three new species registries were found for Rio Grande do Sul State expanding their occurrence range towards South Brazil. The comparison of climbers' survey sites showed two sharp groups in relation to species composition and traits proportion, Seasonal and Araucaria/Atlantic forest sites, but with no difference of traits frequency between sites. There is a predominance of stem twiners species in all sites, but the relative difference for tendril species increases in Araucaria and Atlantic forest sites. The Asteraceae and Apocynaceae families were the most relevant, contrasting to Seasonal forests of Southeast Brazil. Interesting patterns can be achieved with a more detailed classification of climbing mechanisms and the results found in this study contributes to enhance the knowledge on climbers' traits and diversity in South Brazil.

Trepadeiras são importantes componentes florestais, contribuindo na diversidade e dinâmica de comunidades vegetais. Estudos focados em trepadeiras são escassos e para muitos tipos vegetacionais pouco se sabe sobre a composição de espécies de trepadeiras e seus atributos relevantes para dispersão e estabelecimento. O foco deste estudo é fornecer o primeiro inventário florístico de plantas trepadeiras em uma floresta de Araucária no Brasil, descrevendo as síndromes de dispersão e mecanismos de escalada das espécies e comparando esses atributos e a composição de espécies com outros sítios no Sul do Brasil. Foram encontrados 104 taxa pertencentes a 33 famílias, sendo Asteraceae (22 spp.) e Apocynaceae (14 spp.) as famílias mais ricas. Dentre os mecanismos de escalada, o tipo volúvel (50 spp.) é o mais comum, seguido por gavinhas (20 spp.) e apoiantes (12 spp.), enquanto em relação ès síndromes de dispersão as espécies anemocóricas (65 spp.) são as mais relevantes seguidas por endozoocóricas (28 spp.). Três novos registros de espécies foram encontrados para o Estado do Rio Grande do Sul, expandindo suas extensões de ocorrência para o Sul do Brasil. A comparação entre sítios evidenciou dois grupos nítidos em relação è composição de espécies e proporção de atributos, sítios em florestas sazonais e nas florestas com Araucária e Atlântica, porém não há diferença na frequência dos atributos entre os sítios. Há uma predominância de espécies volúveis em todos os sítios, entretanto a diferença relativa para espécies com gavinhas aumenta nos sítios de floresta com Araucária e Atlântica. As famílias Asteraceae e Apocynaceae foram as mais relevantes, contrastando com florestas sazonais no Sudeste do Brasil. Padrões interessantes podem ser encontrados com uma classificação mais detalhada dos mecanismos de escalada e os resultados encontrados neste estudo contribuem para aumentar o conhecimento sobre os atributos e a diversidade de trepadeiras no Sul do Brasil.

Phylobetadiversity among forest types in the Brazilian Atlantic Forest complex.

Phylobetadiversity is defined as the phylogenetic resemblance between communities or biomes. Analyzing phylobetadiversity patterns among different vegetation physiognomies within a single biome is crucial to understand the historical affinities between them. Based on the widely accepted idea that different forest physiognomies within the Southern Brazilian Atlantic Forest constitute different facies of a single biome, we hypothesize that more recent phylogenetic nodes should drive phylobetadiversity gradients between the different forest types within the Atlantic Forest, as the phylogenetic divergence among those forest types is biogeographically recent. We compiled information from 206 checklists describing the occurrence of shrub/tree species across three different forest physiognomies within the Southern Brazilian Atlantic Forest (Dense, Mixed and Seasonal forests). We analyzed intra-site phylogenetic structure (phylogenetic diversity, net relatedness index and nearest taxon index) and phylobetadiversity between plots located at different forest types, using five different methods differing in sensitivity to either basal or terminal nodes (phylogenetic fuzzy weighting, COMDIST, COMDISTNT, UniFrac and Rao's H). Mixed forests showed higher phylogenetic diversity and overdispersion than the other forest types. Furthermore, all forest types differed from each other in relation phylobetadiversity patterns, particularly when phylobetadiversity methods more sensitive to terminal nodes were employed. Mixed forests tended to show higher phylogenetic differentiation to Dense and Seasonal forests than these latter from each other. The higher phylogenetic diversity and phylobetadiversity levels found in Mixed forests when compared to the others likely result from the biogeographical origin of several taxa occurring in these forests. On one hand, Mixed forests shelter several temperate taxa, like the conifers Araucaria and Podocarpus. On the other hand, tropical groups, like Myrtaceae, are also very representative of this forest type. We point out to the need of more attention to Mixed forests as a conservation target within the Brazilian Atlantic Forest given their high phylogenetic uniqueness.