ABSTRACT
Mosses host diverse bacterial communities essential for their fitness, nutrient acquisition, stress tolerance, and pathogen defense. Understanding the microbiome's taxonomic composition is the first step, but unraveling their functional capabilities is crucial for grasping their ecological significance. Metagenomics characterizes microbial communities by composition, while metatranscriptomics explores gene expression, providing insights into microbiome functionality beyond the structure. Here, we present for the first time a metatranscriptomic study of two moss species, Hypnum cupressiforme (Hedw.) and Platyhypnidium riparioides (Hedw.) Dixon., renowned as key biomonitors of atmospheric and water pollution. Our investigation extends beyond taxonomic profiling and offers a profound exploration of moss bacterial communities. Pseudomonadota and Actinobacteria are the dominant bacterial phyla in both moss species, but their proportions differ. In H. cupressiforme, Actinobacteria make up 62.45% and Pseudomonadota 32.48%, while in P. riparioides, Actinobacteria account for only 25.67% and Pseudomonadota 69.08%. This phylum-level contrast is reflected in genus-level differences. Our study also shows the expression of most genes related to nitrogen cycling across both microbiomes. Additionally, functional annotation highlights disparities in pathway prevalence, including carbon dioxide fixation, photosynthesis, and fatty acid biosynthesis, among others. These findings hint at potential metabolic distinctions between microbial communities associated with different moss species, influenced by their specific genotypes and habitats. The integration of metatranscriptomic data holds promise for enhancing our understanding of bryophyte-microbe partnerships, opening avenues for novel applications in conservation, bioremediation, and sustainable agriculture.
ABSTRACT
During the review of species of the Sematophyllaceae family deposited in national herbaria, it was possible to expand the occurrence record of Meiothecium boyanum (Müll.Hal.) Mitt. in Brazil. Currently, the confirmed occurrence of the species is limited to the States of Bahia, Goiás, Rio de Janeiro, Rio Grande do Sul and São Paulo, although only the State of Bahia is mentioned in Flora e Funga do Brasil 2022. With this work, the species had its record confirmed for Minas Gerais and Pernambuco States.
Durante a revisão de espécies da família Sematophyllaceae depositadas em herbários nacionais foi possível ampliar o registro de ocorrência de Meiothecium boryanum (Müll.Hal.) Mitt. no Brasil. Atualmente a ocorrência confirmada da espécie se limita aos Estados da Bahia, Goiás, Rio de Janeiro, Rio Grande do Sul e São Paulo, embora seja citada apenas o Estado da Bahia no Flora e Funga do Brasil 2022. Com este trabalho, a espécie teve seu registro confirmado também para os estados de Minas Gerais e Pernambuco.
ABSTRACT
We present an integrative molecular and morphological study of subaquatic representatives of the genus Pseudohygrohypnum (Pylaisiaceae, Bryophyta), supplemented by distribution modelling of the revealed phylogenetic lineages. Phylogenetic analyses of nuclear and plastid datasets combined with the assemble species by automatic partitioning (ASAP) algorithm revealed eight distinct species within the traditionally circumscribed P. eugyrium and P. subeugyrium. These species are therefore yet another example of seemingly widely distributed taxa that harbour molecularly well-differentiated lineages with narrower distribution ranges. Studied accessions that were previously assigned to P. eugyrium form three clearly allopatric lineages, associated with temperate regions of Europe, eastern North America and eastern Asia. Remarkably, accessions falling under the current morphological concept of P. subeugyrium were shown to be even more diverse, containing five phylogenetic lineages. Three of these lineages occur under harsh Asian continental climates from cool-temperate to Arctic regions, while the remaining two, referred to P. subeugyrium s.str. and P. purpurascens, have more oceanic North Atlantic and East Asian distributions. Niche identity and similarity tests suggested no similarity in the distributions of the phylogenetically related lineages but revealed the identity of two East Asian species and the similarity of two pairs of unrelated species. A morphological survey confirmed the distinctness of all eight phylogenetic lineages, requiring the description of five new species. Pseudohygrohypnum appalachianum and P. orientale are described for North American and East Asian plants of P. eugyrium s.l., while P. sibiricum, P. subarcticum and P. neglectum are described for the three continental, predominantly Asian lineages of P. subeugyrium s.l. Our results highlight the importance of nontropical Asia as a center of bryophyte diversity. Phylogenic dating suggests that the diversification of subaquatic Pseudohygrohypnum lineages appeared in late Miocene, while mesophilous species of the genus split before Miocene cooling, in climatic conditions close to those where the ancestor of Pseudohygrohypnum appeared. We speculate that radiation of the P. subeugyrium complex in temperate Asia might have been driven by progressive cooling, aridification, and increases in seasonality, temperature and humidity gradients. Our results parallel those of several integrative taxonomic studies of North Asian mosses, which have resulted in a number of newly revealed species. These include various endemics from continental areas of Asia suggesting that the so-called Rapoport's rule of low diversity and wide distribution range in subpolar regions might not be applicable to bryophytes. Rather, the strong climatic oscillations in these regions may have served as a driving force of speciation and niche divergence.
Subject(s)
Bryophyta , Bryopsida , Phylogeny , Phylogeography , Asia, Eastern , AsiaABSTRACT
Porotrichum squarrosum has never been reported from Brazil and it is a new record. While revising herbarium specimens we found a specimen named Pireella squarrosa (currently Porotrichum), identified by Massimo Mastracci. We have compared this specimen with records from literature and several hundreds of specimens and found that among specimens previously determined as P. substriatum several belong to P. squarrosum. These taxa are a quite common in Brazil ranging from Amazon, Atlantic Forest to Cerrado phytogeographical domains at elevations from near sea level to about 600 m. These taxa are fast differentiated by the squarrose leaves, spur costa at back and absence of stem central strand in P. squarrosum against to complanate leaves, without spurowed costa at back and presence of central strand in P. substriatum.
Porotrichum squarrosum nunca foi reportado para o Brasil e trata-se de um novo registro. Durante a revisão de espécimes de herbário, o nome Pireella squarrosa (atualmente Porotrichum), identificado por Massimo Mastracci foi encontrado em algumas plantas. Após a comparação com literatura e centenas de espécimens de herbário, verificamos que P. squarrosum é uma espécie comum no Brasil, ocorrendo desde o domínio fitogeográfico da Amazônia até a Mata Atlântica e Cerrado em elevações desde o nível do mar até próximo 600 m. Esses táxons são rapidamente diferenciados pelos filídios esquarrosos, costa com esporão dorsal e ausência de banda central de estereides no caulídio em P. squarrosum em contraposição a filídios complanados, sem costa esporada dorsalmente e presença de banda central de estereides no caulídio em P. substriatum.
ABSTRACT
Heavy metals (HMs) are released into the environment by many human activities and persist in water even after remediation. The efficient filtration of solubilized HMs is extremely difficult. Phytoremediation appears a convenient tool to remove HMs from polluted water, but it is limited by the choice of plants able to adapt to filtration of polluted water in terms of space and physiological needs. Biomasses are often preferred. Aquatic moss biomasses, thanks to gametophyte characteristics, can act as live filtering material. The potential for phytoremediation of Hypnales aquatic mosses has been poorly investigated compared to aquatic macrophytes. Their potential is usually indicated as a tool for bioindication and environmental monitoring more than for pollutant removal. When phytoremediation has been considered, insufficient attention has been paid to the adaptability of biomasses to different needs. In this study the heavy metal uptake of moss Taxiphyllum barbieri grown in two different light conditions, was tested with high concentrations of elements such as Pb, Cd, Zn, Cu, As, and Cr. This moss produces dense mats with few culture needs. The experimental design confirmed the capacity of the moss to accumulate HMs accordingly to their physiology and then demonstrated that a significant proportion of HMs was accumulated within a few hours. In addition to the biosorption effect, an evident contribution of the active simplistic mass can be evidenced. These reports of HM accumulation within short time intervals, show how this moss is particularly suitable as an adaptable bio-filter, representing a new opportunity for water eco-sustainable remediation.
