Genetic diversity and its distribution, both within and between populations, may be determined by micro-evolutionary processes, such as the demographic history of populations, natural selection, and gene flow. In plants, indices of genetic diversity (e.g., k, h and π) and structure (e.g., F_ST) are typically inferred from sequences of chloroplast markers. Given the recent advances and popularization of molecular techniques for research in population genetics, phylogenetics, phylogeography, and ecology, we adopted a scientometric approach to compile evidence on the recent trends in the use of cpDNA sequences as markers for the analysis of genetic diversity in botanical studies, over the years. We also used phylogenetic modeling to assess the relative contribution of relatedness or ecological and reproductive characters to the genetic diversity of plants. We postulated that genetic diversity could be defined not only by microevolutionary factors and life history traits, but also by relatedness, so that species more closely related phylogenetically would have similar genetic diversities. We found a clear tendency for an increase in the number of studies over time, confirming the hypothesis that the advances in the area of molecular genetics have supported the accumulation of data on the genetic diversity of plants. However, we found that the vast majority of these data have been produced by Chinese authors, and refer specifically to populations of Chinese plants. Most of the data on genetic diversity have been obtained for species in the International Union for Conservation of Nature (IUCN) category NE (Not Evaluated), which indicates a relative lack of attention on threatened species. In general, we observed very high F_ST values in the groups analyzed and, as we focused primarily on species that have not been evaluated by the IUCN, the number of plant species that are threatened with extinction may be much greater than that indicated by the listing of this organization. We also found that the number of haplotypes (k) was influenced by the type of geographic distribution of the plant, while haplotype diversity (h) was affected by the type of flower, and the fixation index (F_ST), by the type of habitat. The plant species most closely-related phylogenetically have similar levels of genetic diversity. Overall, then, it will important to consider phylogenetic dependence in future studies that evaluate the effects of life-history traits on plant genetic diversity.

Stryphnodendron adstringensis a medicinal plant belonging to the Leguminosae family, and it is commonly found in the southeastern savannas, endemic to the Cerrado biome. The goal of this study was to assemble and annotate the chloroplast genome ofS. adstringensand to compare it with previously known genomes of the mimosoid clade within Leguminosae. The chloroplast genome was reconstructed usingde novoand referenced-based assembly of paired-end reads generated by shotgun sequencing of total genomic DNA. The size of theS. adstringenschloroplast genome was 162,169 bp. This genome included a large single-copy (LSC) region of 91,045 bp, a small single-copy (SSC) region of 19,014 bp and a pair of inverted repeats (IRa and IRb) of 26,055 bp each. TheS. adstringenschloroplast genome contains a total of 111 functional genes, including 77 protein-coding genes, 30 transfer RNA genes, and 4 ribosomal RNA genes. A total of 137 SSRs and 42 repeat structures were identified inS. adstringenschloroplast genome, with the highest proportion in the LSC region. A comparison of theS. adstringenschloroplast genome with those from other mimosoid species indicated that gene content and synteny are highly conserved in the clade. The phylogenetic reconstruction using 73 conserved coding-protein genes from 19 Leguminosae species was supported to be paraphyletic. Furthermore, the noncoding and coding regions with high nucleotide diversity may supply valuable markers for molecular evolutionary and phylogenetic studies at different taxonomic levels in this group.

Alternative sources of fuel have been a concern in the last few decades. The growth of urbanization and industrialization will lead to the exhaustion of fossil fuels, attracting studies on alternative routes. The main aim of this study was to produce biodiesel from waste cooking oil (WCO) by methyl transesterification using sodium hydroxide as a catalyst. For this, the physicochemical parameters of biodiesel were studied in triplicate (density, acidity, saponification, viscosity, corrosiveness to copper, visual appearance, and cloud point). An analysis by thin layer chromatography and infrared spectrometry was also performed. The increase in yield (83.3%) was directly proportional to the increase in the catalyst (0.22 g of NaOH). The infrared absorption spectra of WCO and biodiesel showed the presence of common and singular bands of each material. Furthermore, a simple and low-cost mechanism was proposed for purifying glycerol. The spectra of glycerol versus purified glycerin showed that the glycerin produced was pure, being used in the formulation of bioplastic. The product was checked for biodegradation and photodegradation, with incredible soil-degradation times of 180 days and photodegradation of only 60 days. In this way, biodiesel production from WCO showed environmentally friendly proposals and applicability. As the next steps, it is necessary to test the biodiesel produced in combustion engines and improve the bioplastic production, including a spectroscopic characterization and extensive biodegradation testing.

SARS-CoV-2, the virus responsible for COVID-19, has undergone significant genetic evolution since its emergence in 2019. This study examines the genomic diversity of SARS-CoV-2 in Brazil after the worst phase of the pandemic, the wider adoption of routine vaccination, and the abolishment of other non-pharmacological preventive measures from July 2022 to July 2024 using 55,951 sequences retrieved from the GISAID database. The analysis focuses on the correlation between confirmed COVID-19 cases, sequencing efforts across Brazilian states, and the distribution and evolution of viral lineages. Our findings reveal significant regional disparities in genomic surveillance, with São Paulo and Rio de Janeiro recovering the largest number of genomes, while Tocantins and Amazonas showed higher sequencing rates relative to their reported case numbers, indicating proactive surveillance efforts. We identified 626 distinct SARS-CoV-2 lineages circulating in Brazil, with dominant subvariants shifting over time from BA.5 in 2022 to XBB and JN.1 in 2023–2024. The emergence of new subvariants in this new epidemiological scenario underscores the importance of ongoing genomic surveillance to track viral evolution and inform public health strategies, providing valuable information to update vaccines and implement other measures, such as lockdowns, mask usage, social distancing, health education, and self-testing.

The IUCN Red List categorizes species based on their geographical distribution and population size. However, attributes such as genetic information are not yet considered. We compiled information on genetic diversity (HE, HO) and inbreeding coefficient (f) along with their ecological attributes (IUCN category, migratory habit, forest dependence and habitat type) from a literature survey to assess whether bird species categorized as being of highest conservation concern display the lowest genetic diversity. We used generalized linear mixed models (GLMM) to test whether avian species with less inclusive characteristics (e.g., taxa with small geographical distributions or low dispersal capability) display lower genetic diversity than those classified as Least Concern (LC). We used hylogenetic generalized least squares (pGLS) to account for phylogenetic independence of predictor variables and to verify robustness of GLMMs (generalized linear mixed models). In general, GLMM revealed more significant relationships among ecological attributes and genetic diversity patterns. After accounting for phylogenetic independence, the highest average heterozygosity values were observed in species falling under the LC category; non–migratory birds showed lower HO and HE average values than migratory birds, while non–forest birds showed lower heterozygosity than forest birds. Hence, we corroborate our hypothesis that genetic diversity of birds is lower in species of high conservation concern. We hope our results promote further studies on genetic diversity of bird populations. Lastly, we propose the incorporation of genetic data as metrics in the assessment of bird conservation status.

Brazil currently ranks second in absolute deaths by COVID-19, even though most of its population has completed the vaccination protocol. With the introduction of Omicron in late 2021, the number of COVID-19 cases soared once again in the country. We investigated in this work how lineages BA.1 and BA.2 entered and spread in the country by sequencing 2173 new SARS-CoV-2 genomes collected between October 2021 and April 2022 and analyzing them in addition to more than 18,000 publicly available sequences with phylodynamic methods. We registered that Omicron was present in Brazil as early as 16 November 2021 and by January 2022 was already more than 99% of samples. More importantly, we detected that Omicron has been mostly imported through the state of São Paulo, which in turn dispersed the lineages to other states and regions of Brazil. This knowledge can be used to implement more efficient non-pharmaceutical interventions against the introduction of new SARS-CoV variants focused on surveillance of airports and ground transportation.