Abstract. In the Amazonian rain forest, major parts of trees and shrubs are covered by epiphytic cryptogams of great taxonomic variety, but their relevance in biosphere–atmosphere exchange, climate processes, and nutrient cycling is largely unknown. As cryptogams are poikilohydric organisms, they are physiologically active only under moist conditions. Thus, information on their water content (WC) as well as temperature and light conditions experienced by them are essential to analyze their impact on local, regional, and even global biogeochemical processes. In this study, we present data on the microclimatic conditions, including water content, temperature, and light conditions experienced by epiphytic bryophytes along a vertical gradient, and combine these with above-canopy climate data collected at the Amazon Tall Tower Observatory (ATTO) in the Amazonian rain forest between October 2014 and December 2016. While the monthly average of above-canopy light intensities revealed only minor fluctuations over the course of the year, the light intensities experienced by the bryophytes varied depending on the location within the canopy, probably caused by individual shading by vegetation. In the understory (1.5 m), monthly average light intensities were similar throughout the year, and individual values were extremely low, remaining below 3 µmol m−2 s−1 photosynthetic photon flux density more than 84 % of the time. Temperatures showed only minor variations throughout the year, with higher values and larger height-dependent differences during the dry season. The indirectly assessed water content of bryophytes varied depending on precipitation, air humidity, dew condensation, and bryophyte type. Whereas bryophytes in the canopy were affected by diel fluctuations of the relative humidity and condensation, those close to the forest floor mainly responded to rainfall patterns. In general, bryophytes growing close to the forest floor were limited by light availability, while those growing in the canopy had to withstand larger variations in microclimatic conditions, especially during the dry season. For further research in this field, these data may be combined with CO2 gas exchange measurements to investigate the role of bryophytes in various biosphere–atmosphere exchange processes, and could be a tool to understand the functioning of the epiphytic community in greater detail.

This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0), which permits reproduction, adaptation, and distribution provided the original author and source are credited. Resumo Este trabalho relata a ocorrência de espécies de fungos dos gêneros Chlorophyllum Massee e Macrolepiota Singer, este último ainda não registrado para São Gabriel, Rio Grande do Sul, Brasil. A área de estudo está localizada no Bioma Pampa, sendo as coletas realizadas entre abril de 2011 e maio de 2012. Os resultados indicam que a micobiota da área é representada por cinco espécies, como segue: Macrolepiota gracilenta (Krombh) Wasser, Macrolepiota fuligineosquarrosa Malençon, Macrolepiota procera (Scop.) Singer, Chlorophyllum rachodes (Vittad.) Vellinga e Chlorophyllum molybdites (G. Mey.) Massee. Dessa forma, são apresentadas chaves para a identificação dessas espécies e registradas duas novas ocorrências de Macrolepiota, respectivamente, para o Brasil e Rio Grande do Sul.

Endophyte biology is a branch of science that contributes to the understanding of the diversity and ecology of microorganisms that live inside plants, fungi, and lichen. Considering that the diversity of endolichenic fungi is little explored, and its phylogenetic relationship with other lifestyles (endophytism and saprotrophism) is still to be explored in detail, this paper presents data on axenic cultures and phylogenetic relationships of three endolichenic fungi, isolated in laboratory. Cladonia curta Ahti & Marcelli, a species of lichen described in Brazil, is distributed at three sites in the Southeast of the country, in mesophilous forests and the Cerrado. Initial hyphal growth of Xylaria spp. on C. curta podetia started four days after inoculation and continued for the next 13 days until the hyphae completely covered the podetia. Stromata formation and differentiation was observed, occurring approximately after one year of isolation and consecutive subculture of lineages. Phylogenetic analyses indicate lineages of endolichenic fungi in the genus Xylaria, even as the morphological characteristics of the colonies and anamorphous stromata confirm this classification. Our preliminary results provide evidence that these endolichenic fungi are closely related to endophytic fungi, suggesting that the associations are not purely incidental. Further studies, especially phylogenetic analyses using robust multi-locus datasets, are needed to accept or reject the hypothesis that endolichenic fungi isolated from Xylaria spp. and X. berteri are conspecific.

In the current study, we present the molecular characterization of an endophyte fungus associated with the leaves of Deschampsia antarctica Desv. (Poaceae), a monocot species native to Antarctica. The isolate was obtained from 90 leaf fragments from two distinct collection sites, both located on Half Moon Island, South Shetland Islands and Maritime Antarctica. The internal transcribed spacer region (ITS) was sequenced and the endophytic fungus was identified as belonging to the genus Juncaceicola Tennakoon, Camporesi, Phook and K.D. Hyde (99% nucleotide sequence identity). When compared to all fungi of the genus Juncaceicola deposited in data base, our isolate showed greater proximity with Juncaceicola typharum, however, because it presents a low bootstrap value to be considered a new species, we treat it as Juncaceicola cf. typharum. Moreover, the identification of our isolate as belonging to the genus Juncaceicola makes this the first occurrence of a species of this genus to be associated with the leaves of Antarctic plants. This work is considered as a starting point for other studies with fungi of this genus associated with leaves of Deschampsia antarctica, as it presents results from two collection points on a single Antarctic island, suggesting that new sites and new Antarctic islands should be explored.

Cryptogamic organisms such as bryophytes and lichens cover most surfaces within tropical forests, yet their impact on the emission of biogenic volatile organic compounds is unknown. These compounds can strongly influence atmospheric oxidant levels as well as secondary organic aerosol concentrations, and forest canopy leaves have been considered the dominant source of these emissions. Here we present cuvette flux measurements, made in the Amazon rainforest between 2016–2018, and show that common bryophytes emit large quantities of highly reactive sesquiterpenoids and that widespread lichens strongly uptake atmospheric oxidation products. A spatial upscaling approach revealed that cryptogamic organisms emit sesquiterpenoids in quantities comparable to current canopy attributed estimates, and take up atmospheric oxidation products at rates comparable to hydroxyl radical chemistry. We conclude that cryptogamic organisms play an important and hitherto overlooked role in atmospheric chemistry above and within tropical rainforests.