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Structural and physiological leaf traits and their plasticity were compared in the hemiepiphyte Vanilla phaeantha. This species grows along a phorophyte reaching different understorey positions and exhibiting diverse responses to environment changes. We analysed three height strata above the ground, establishing a light gradient, and considering seasonal water fluctuations. The upper leaves had higher area and mass and were less pigmented. The dry season induced a reduction of approximately 2 h of stomatal opening over the diel 24 h crassulacean acid metabolism (CAM) cycle in the leaves at all understorey positions. The leaves more exposed to sunlight were larger with higher titratable acidity during the rainy season, while the leaves near the ground maintained the same rates of stomatal conductance and nocturnal acidification between seasons, with lowest values of carbon isotopes in the rainy season. Our research showed that some structural leaf traits (such as specific leaf mass, biomass, and saturated water content) are sensitive to variation in understorey position. In contrast, other physiological traits (stomatal conductance, transpiration, and fluorescence parameters) are more sensitive to seasonal variations. The results are a novelty in assessing the variation of CAM along the same plant in a height gradient and under field conditions. Surviving in conditions of water fluctuation and light heterogeneity by plants requires to be plastic. We showed that the hemiepiphyte Vanilla phaeantha adjusts leaf traits and their metabolism for atmospheric CO2 capture in function of the vertical gradient of the understorey (that has different light availability and air humidity), and according to water seasonality. The morphological traits mainly varied according to the understorey position, while physiological ones were more sensitive to seasonal variations. [ABSTRACT FROM AUTHOR]

Tillandsia recurvata is an epiphytic plant commonly found in tropical regions and colonizes tree trunks, fences, and power wires. This plant plays an important role in interacting with trees, sharing microorganisms, and performing specific functions in the process of tree colonization. The objective of this study was to evaluate and compare the microbiomes of T. recurvata collected from two different locations (trees and fences) and two plant tissues (leaves and roots). The hypothesis of this study was that the microbiome of T. recurvata is composed of microorganisms that would provide nutritional support to compensate for the lack of nutrients in a particular growth support. The results showed significant differences in microbial diversity between trees and fences, with trees exhibiting higher richness and more complex microbial networks. Proteobacteria was the most prevalent bacterial phylum, with Actinobacteria and Sphingomonas also playing key roles in nitrogen fixation and plant growth. Fungal communities were similar across locations, with Ascomycota and Basidiomycota being predominant, but Paraconiothyrium and Nigrospora showed significant differences in abundance between trees and fences. Functional analysis indicated similar metabolic profiles across leaf and root samples, with key functions for T. recurvata including carbohydrate and amino acid metabolism, stress control, and biofertilization. [ABSTRACT FROM AUTHOR]

In epiphytes, aerial roots are important to combat water‐deficient, nutrient‐poor, and high‐irradiance microhabitats. However, whether aerial roots can respond to gravity and whether auxin plays a role in regulating aerial root development remain open‐ended questions. Here, we investigated the gravitropic response of the epiphytic orchid Phalaenopsis aphrodite. Our data showed that aerial roots of P. aphrodite failed to respond to gravity, and this was correlated with a lack of starch granules/statolith sedimentation in the roots and the absence of the auxin efflux carrier PIN2 gene. Using an established auxin reporter, we discovered that auxin maximum was absent in the quiescent center of aerial roots of P. aphrodite. Also, gravity failed to trigger auxin redistribution in the root caps. Hence, loss of gravity sensing and gravity‐dependent auxin redistribution may be the genetic factors contributing to aerial root development. Moreover, the architectural and functional innovations that achieve fast gravitropism in the flowering plants appear to be lost in both terrestrial and epiphytic orchids, but are present in the early diverged orchid subfamilies. Taken together, our findings provide physiological and molecular evidence to support the notion that epiphytic orchids lack gravitropism and suggest diverse geotropic responses in the orchid family. Summary statement: The architectural and functional innovations required to achieve fast gravitropism in flowering plants are lost in terrestrial and epiphytic orchids, but present in the early diverged orchid subfamilies. Our data suggest diverse geotropic responses in the orchid family. [ABSTRACT FROM AUTHOR]

Premise: Vascular epiphytes of tropical montane cloud forests are vulnerable to climate change, particularly as cloud bases elevate and reduce atmospheric inputs to the system. However, studies have generally focused on epiphytes in contiguous forests, with little research being done on epiphytes on isolated pasture trees. We investigated water relations of pasture‐tree epiphytes at three sites located below and above the elevation of the average cloud base in Monteverde, Costa Rica. Methods: We measured sap velocity and four microclimate variables in both the dry and wet season of 2018. We also measured functional traits, including pressure volume (PV) curves, predawn/midday water potential, and various lab‐based water relations traits. We used linear mixed models to assess the correlation between microclimate and sap velocity in both seasons and ANOVA to assess the variation in PV curve and water potential variables. Results: The turgor loss point generally increased from the wettest to driest site. However, this trend was driven primarily by the increasing prevalence of leaf succulence at drier sites. Microclimatic variables correlated strongly with sap velocity in the wet season, but low soil moisture availability caused this correlation to break down during the dry season. Conclusions: Our results emphasize the vulnerability of cloud forest epiphytes to rising cloud bases. This vulnerability may be more severe in pasture trees that lack the potential buffer of surrounding forest, but additional research that directly compares the canopy microclimate conditions between forest and pasture trees is needed to confirm this possibility. [ABSTRACT FROM AUTHOR]

The Aegle marmelos tree holds immense religious significance in India. Not only do indigenous communities use it, but so do the general populace. Traditional medicine makes use of the whole plant. In addition to its analgesic and antioxidant effects, the plant also possesses antiviral, antifungal, and antibacterial capabilities. The term "Epiphytes" describes the fungal colonies that many endophytic fungi establish on the outside of their host plants. However, there are species that nest in the interstitial and intracellular regions of their host plants; these are known as endophytic species. Endophytes, after interacting with the Bael plant as a host, confer stress tolerance and the capacity to produce bioactive chemicals. It is known that Aegle marmelos include several endophytes. In this study, we detailed the process of isolating ten fungal endophytes from various plant tissues, including bark, roots, fruits, stems and leaves. [ABSTRACT FROM AUTHOR]

Microbiota associated with host–parasite relationships offer an opportunity to explore interactions among plants, parasites, and microbes, thereby contributing to the overall complexity of community structures. The dynamics of ecological interactions between parasitic plants and their hosts in arid environments remain largely understudied, especially in Africa. This study aimed to examine the bacterial communities of Cuscuta epithymum L. (clover dodder), an epiphytic parasitic plant, and its host, Ziziphus lotus L. (jujuba), in an arid environment. Our goal was to uncover the ecological complexities of microbial communities within the framework of plant–plant interactions. We conducted a comprehensive analysis of the bacterial composition and diversity within populations of the C. epithymum parasite, the infected- and non-infected jujuba host, and their interface at the shoots of the host. This involved amplicon sequencing, targeting the V5–V6 regions of the 16S rRNA gene. A total of 5680 amplicon sequence variants (ASVs) were identified, with Pseudomonadota, Bacillota, and Actinobacteriota being prevalent phyla. Among the bacterial communities, three genera were dominant: Cutibacterium, Staphylococcus, and Acinetobacter. Interestingly, analyses of alpha-diversity (p = 0.3 for Shannon index and p = 0.5 for Simplon index) and beta-diversity (PERMANOVA, with p-values of 0.6 and 0.3) revealed no significant differences between Cuscuta-infected and non-infected jujube shrubs, suggesting a shared shoot endophytic bacteriome. This finding advances our comprehension of microbial communities linked to plant–parasite interactions in the arid environments of Africa. Further research on various hosts is required to confirm plant-to-plant bacterial transmission through Cuscuta infection. Additionally, studies on functional diversity, cytology, ecophysiology and the mechanisms by which bacterial communities transferred between host and parasite are necessary. [ABSTRACT FROM AUTHOR]

Large tropical trees are rightly perceived as supporting a plethora of organisms. However, baseline data about the variety of taxa coexisting on single large tropical trees are lacking and prevent a full understanding of both the magnitude of biodiversity and the complexity of interactions among organisms in tropical rainforests. The two main aims of the research program "Life on Trees" (LOT) are (1) to establish baseline knowledge on the number of eukaryote species supported/hosted by the above-ground part of a single tropical tree and (2) to understand how these communities of organisms are assembled and distributed on or inside the tree. To achieve the first goal, we integrated a set of 36 methods for comprehensively sampling eukaryotes (plants, fungi, animals, protists) present on a tropical tree. The resulting LOT protocol was conceived and implemented during projects in the Andean Amazon region and is proposed here as a guideline for future projects of a similar nature. To address the second objective, we evaluated the microclimatic differences between tree zones and tested state-of-the-art terrestrial laser scanning (TLS) and positioning technologies incorporating satellite and fixed base station signals (dGNSS). A marked variation in temperature and relative humidity was detected along a 6-zones Johansson scheme, a tree structure subdivision system commonly used to study the stratification of epiphytic plants. Samples were collected from these six zones, including three along the trunk and three in the canopy. To better understand how different tree components (e.g., bark, leaves, fruits, flowers, dead wood) contribute to overall tree biodiversity, we categorized observations into communities based on Johansson zones and microhabitats. TLS was an essential aid in understanding the complex tree architecture. By contrast, the accuracy of positioning samples in the tree with dGNSS was low. Comprehensively sampling the biota of individual trees offers an alternative to assessing the biodiversity of fewer groups of organisms at the forest scale. Large old tropical trees provide a wealth of microhabitats that encompass a wide range of ecological conditions, thereby capturing a broad spectrum of biodiversity. [ABSTRACT FROM AUTHOR]

Marine ecosystems are important in discovering novel fungi with interesting metabolites that have shown great potential in pharmaceutical and biotechnological industries. Seagrasses, the sole submerged marine angiosperm, host diverse fungal taxa with mostly unknown metabolic capabilities. They are considered to be one of the least studied marine fungal habitats in the world. This review gathers and analyzes data from studies related to seagrasses-associated fungi, including taxonomy and biogeography, and highlights existing research gaps. The significance of the seagrass–fungal associations remains largely unknown, and current understanding of fungal diversity is limited to specific geographical regions such as the Tropical Atlantic, Mediterranean, and Indo-Pacific. Our survey yielded 29 culture-dependent studies on seagrass-associated endophytic and epiphytic fungi, and 13 miscellaneous studies, as well as 11 meta-studies, with no pathogenic true fungi described. There is a significant opportunity to expand existing studies and conduct multidisciplinary research into novel species and their potential applications, especially from understudied geographical locations. Future research should prioritize high-throughput sequencing and mycobiome studies, utilizing both culture-dependent and -independent approaches to effectively identify novel seagrass-associated fungal taxa. [ABSTRACT FROM AUTHOR]

There are a number of rather anecdotal reports of plant growth on power cables in the Americas, but until now there has been no systematic attempt to gauge the geographical extension of this phenomenon nor a documentation of the diversity of species found there. Using observations from the participatory science data platform iNaturalist and the scientific literature, we document almost 700 occurrences of more than 40 species of vascular plants and three lichen species on power cables with a geographical distribution over 7000 km from the southern United States to northern Argentina. Based on these observations we discuss the ecological conditions of plant growth on power cables in terms of climate; elevational distribution; and the morphological, physiological, and life history traits that allow the observed set of species to thrive on this anthropic structure. [ABSTRACT FROM AUTHOR]

Premise of research. In ecosystems where they are common, vascular epiphytes usually interact positively with both their hosts and other epiphytes. However, there are no integrative studies simultaneously analyzing both host-epiphyte and epiphyte-epiphyte associations in ecosystems with a high abundance of vascular epiphytes, such as cloud forests. Most studies have described host-epiphyte associations, but there is a lack of studies evaluating the type of associations established between vascular epiphytes with different growth forms, reproductive states, and taxonomic identities. The goal of this study was to describe the host-epiphyte and epiphyte-epiphyte associations in a cloud forest in central Mexico. Moreover, we evaluated the effect of vascular epiphyte reproductive state, growth form, and taxonomic identity on those associations. Methodology. We first described the host and vascular epiphyte species in the community. Then all host-epiphyte and epiphyte-epiphyte associations were recorded. Pivotal results. All types of associations were recorded among both host-epiphyte (random: 44%; positive: 29%; negative: 27%) and epiphyte-epiphyte (random: 69%; positive: 15%; negative: 16%) associations. Most epiphytes were hosted by four phorophyte species; however, the most abundant phorophytes hosted few or no epiphytes. Epiphyte-epiphyte conspecific associations were mostly positive, whereas the heterospecific associations were predominantly random. At the community level, this pattern did not vary between reproductive states. Associations between heterospecific epiphytes with different growth forms were predominantly random but were positive between conspecifics. Epiphytes with creeping and rosette growth forms established negative associations with their neighbors. Conclusions. Our results show the importance and complexity of the host-epiphyte and epiphyte-epiphyte associations established. To our knowledge, this is the first study in which the epiphyte-epiphyte and host-epiphyte associations and the effect of epiphyte growth form and reproductive state are evaluated. [ABSTRACT FROM AUTHOR]

Epidermal wax is strategically situated at the interface between plants and air; therefore, it plays a key role in plants' interactions with their surroundings. It is also unstable and susceptible to light intensity. Hosta plants are shade-loving herbs with admirable flowers and leaves. Hosta 'Halcyon' and Hosta ensata F. Maek. are two species of Hosta with a glaucous and a glossy appearance, respectively. Light intensity can affect the composition of epicuticular wax on the leaf surface, which influences the leaf color phenotype and ornamental value. In this paper, the crystal micromorphology, content, and components of epicuticular wax on the leaves of two species of Hosta under different light conditions (10%-, 30%-, 50%-, 70%-, and 100%-intensity sunlight, relative light intensity (RLI)) have been studied using pot experiments. The results indicate that the epicuticular wax crystals of H. 'Halcyon' and H. ensata are tubular and platelet-like, respectively. The wax crystals of H. 'Halcyon' melted and formed a thick crust under 100% RLI, and those of H. ensata melted and formed a thick crust under 70% and 100% RLI conditions. The primary ingredients of the epicuticular wax of the two species of Hosta contained primary alcohols, alkanes, fatty acids, and esters; β-diketones were only detected in H. 'Halcyon'. The quantity of epicuticular wax of H. 'Halcyon' reduced at first and then increased with an RLI increase, achieving its lowest value at 50% RLI, but that of H. ensata declined little by little. The amounts of C28 primary alcohols, C31 alkanes, and C18 fatty acids were significantly higher than those of other carbon atoms in the two genotypes of Hosta. The C31β-diketones content decreased with the increase in light intensity, which caused the white frost phenotype to gradually weaken in H. 'Halcyon'. [ABSTRACT FROM AUTHOR]

Purpose: Nitrogen emissions from human activities are contributing to elevated levels of eutrophication in coastal ecosystems. Mechanisms involved in marine eutrophication show strong geographical variation. Existing life cycle impact assessment (LCIA) and absolute environmental sustainability assessment (AESA) methods for marine eutrophication do not adequately represent this variability, do not have a full global coverage, and suffer from other limitations, such as poor estimation of coastal residence times. This study aims to advance LCIA and AESA for marine eutrophication. Methods: We aligned and combined recent advancements in marine eutrophication LCIA and AESA methods into one method. By re-running models underlying the combined methods and incorporating additional data sources, we included marine regions missing in previous methods and improved fate modeling, with the inclusion of denitrification and plant uptake in the air emission-terrestrial deposition pathway. To demonstrate and validate our method, we applied it in a case study. Results: The developed method allows the assessment of marine eutrophication impacts from emissions to soil, freshwater, and air at high resolution (0.083° and 2° × 2.5° for inland and air emissions, respectively) and spatial coverage (all ice-free global continents). In the case study, we demonstrate the added value of our method by showing that the now quantified spatial variability within spatial units, e.g., river basins, can be large and have a strong influence on the modeled marine eutrophication from the case study. Compared to existing methods, our method identifies larger occupations of safe operating space for marine eutrophication, mainly due to the high resolution of the coastal compartment, reflecting a more realistic areal extent of marine eutrophication impacts. Conclusions: Although limited by factors such as simulations based on a single reference year for modeling inland and air fate, our method is readily applicable to assess the marine eutrophication impact of nitrogen emitted to any environmental compartment and relate it to the safe operating space. With substantial advancement of existing approaches, our method improves the basis for decision-making for managing nitrogen and reducing emissions to levels within the safe operating space. [ABSTRACT FROM AUTHOR]

During the 11th German Antarctic North Victoria Land Expedition in 2015/16, exceptionally well-preserved permineralized Kykloxylon stems—the wood of the iconic Dicroidium plants of the Gondwanan Triassic—were collected from the Middle to Upper Triassic Helliwell Formation in north Victoria Land, Transantarctic Mountains, Antarctica. Some of these logs show large borings and cavities that are partly filled with multi-layered periderm. This periderm is identical in cell shape and dimensions to isolated flakes of tissue that are superabundant in bulk macerations of Dicroidium-bearing rock samples from different coeval locations in the Transantarctic Mountains. These flakes are interpreted as shed bark fragments of Dicroidium-bearing umkomasialean trees. Various hypotheses on the adaptive advantages of bark shedding are discussed, including the reduction of epiphyte load. Palynological data document an abundance of potentially epiphytic cryptogams (spikemosses and bryophytes) in the environments in which the Dicroidium trees grew, and modern ecosystems with a climate comparable to that of the Late Triassic in Antarctica are in many cases also characterized by a lush epiphyte vegetation. Another advantage could lie in the reduction of infections by phytopathogenic microorganisms, as abundant fungal remains in both the wound periderm and the dispersed periderm flakes indicate.

The majority of the woodland area in Central Europe is composed of managed forests. Although the species diversity and composition, particularly in older forests, may be similar to those of natural or close-to-nature forests, intensive forestry and other human activities have adverse impacts on biodiversity. The present study focused on bryophyte diversity in managed lowland forests, as these have received less attention compared to other types of forests. Our research targeted the area located within the Borská nížina Lowland in south-western Slovakia. In total, 37 forest sampling plots (SPs) were selected, representing five different forest types, namely Quercus, Fraxinus, Robinia, Pinus, and mixed forests. Multivariate statistical analyses were conducted across these forest types to demonstrate variations in bryophyte species richness, composition, and functional traits. Overall, 60 species of bryophytes were identified, of which five were liverworts and 55 were mosses. Epiphytes were the most abundant substrate group in deciduous and mixed stands, while epigeic species prevailed in Pinus forests. Considering environmental factors, the bryophyte diversity was influenced mostly by the forest type and area size of SPs. Clear differences in species composition were observed when comparing coniferous and deciduous stands, as well as non-native Robinia forests and native tree stands. Overall, intensive forest management results in a high concentration of hemerophilous and nitrophilous species, along with the absence of rare and threatened mosses and liverworts. Nevertheless, by adhering to proper management methods, even managed forests can provide suitable habitats for various bryophytes. [ABSTRACT FROM AUTHOR]

Tea gardens are the main economic backbone of the Terai & Dooars region and intermingle with forest areas of northern Bengal in India. The study aims to explore the vascular epiphytic diversity and their zone-wise assemblage pattern on 10 dominant shade trees in the tea gardens. Four years (March 2018-September 2022) of surveys recorded a total of 6,704 individuals that belong to 74 species of 20 families of vascular epiphytes. Considering life forms, the majority of them are holoepiphytes (62.16%), followed by hemiepiphytes (20.27%), accidental epiphytes (13.51%), and facultative epiphytes (2.7%). The predominantly recorded families are Orchidaceae (21 spp.), Araceae (11 spp.), Apocyanaceae with six species, and Piperaceae & Pteridaceae with three species each. Albizia lebbeck (L.) Benth. hosts a maximum of 737 vascular epiphytic assemblages (VEAs), whereas, Gmelina arborea Roxb. has a minimum of 450 VEAs. Vascular epiphytes were also studied for their host specificity using interpolation and extrapolation analyses. The findings of the study show that vascular epiphytic assemblage upon the shade trees of the tea garden has a remarkably high potential to contribute toward epiphytic diversity of this region other than forest and contribute significant ecological impacts. [ABSTRACT FROM AUTHOR]

Trees in urban green areas (UGAs) face various stress-inducing factors that, together with the incidence and severity of damage agents, reduce their growth and health condition. The objective of this study was to characterize the incidence and severity of damage to trees located in 21 UGAs in the city of Texcoco, Mexico, as well as the relationship between their health, green area typology, and urban infrastructure. Using tree damage indicators, the incidence of two damage agents per tree was determined, and seven damage groups were identified: biotic agents, parasitic and epiphytic plants, insects, animals, abiotic agents, and anthropogenic factors. A damage severity index (DSI) was estimated at species level and by green area. Chlorophyll fluorescence was used to assess stress as an indirect measure of tree health condition in UGAs, and surrounding urban infrastructure was classified. A total of 1543 trees were assessed, and 23 damage agents were identified, affecting 9.95 % of the foliage, 10.24 % of the branches, 4.47 % of the trunk, and 0.45 % of the root collar and roots. As for incidence, 60.01 % showed no damage at all, 29.49 % showed only one agent, and 10.5 % showed two agents. Most of the trees at the UGAs were found to be under stress (≤ 0.78) and uncorrelated with DSI; however, the index was different by species and UGA (p ≤ 0.05). Insect damage and poor management practices were associated with the presence of buildings, busy roads, and people congregation areas inside UGAs. [ABSTRACT FROM AUTHOR]

Plant herbivore interactions have long been recognized as a complex interplay influenced by various factors, including plant volatile emissions. Understanding the role of these volatiles in mediating plant predator interactions is crucial for developing sustainable pest management strategies. This study investigated the olfactory preferences of Chrysoperla externa larvae for volatiles emitted by Eucalyptus urograndis leaves, focusing on both seedlings and essential oils (EOs). We used Y-tube olfactometry to compare larval preferences between the clean air and various plant treatments, including undamaged and herbivore-damaged leaves. Chemical analysis of EOs revealed higher concentrations of oxygenated monoterpenes and sesquiterpenes in young and damaged leaves, particularly linalool, which has been implicated in insect attraction. Our results showed a significant preference for volatiles emitted by young damaged leaves over clean air for both seedlings (χ2 = 11.03, p = 0.001) and EOs (χ2 = 9.76, p = 0.002). Chrysoperla externa larvae are significantly attracted to specific volatiles from damaged E. urograndis leaves, suggesting these compounds could serve as cues for natural enemy foraging. Our findings enhance the understanding of plant–predator dynamics and suggest potential applications of eucalyptus plantations to sustain C. externa populations for biocontrol purposes. [ABSTRACT FROM AUTHOR]

The gasification of olive cake is a promising method for converting this material into valuable energy. This work offers interesting results about the effect of equivalence ratio and temperature on the composition and quality of the produced gas obtained during olive cake gasification in a fluidized bed plant with air as a gasification agent. Additionally, the efficiency of the gasification process was evaluated. The results show that, for a specific temperature, an equivalence ratio of 0.3 showed a higher cold gas efficiency. For example, at 850 °C and an equivalence ratio of 0.1, the cold gas efficiency was 22.7%; however, at the same temperature but at an equivalence ratio of 0.3, the cold gas efficiency was increased to 61.2%. In addition, for a constant equivalence ratio, by increasing the operating temperature, there was no significant increase in the lower heating value of the exit gas, and the gas flow was practically constant with temperature, but it varied substantially with the equivalence ratio, reaching values in the range of 3.44–14.89 NL/min (825.6–3573.6 NL/kg feed). Finally, the production of CO, H2, and CH4 is estimated to be higher for tests conducted with an equivalence ratio of 0.3. [ABSTRACT FROM AUTHOR]

Epiphytes develop anatomical features to improve efficiency of the uptake of water and nutrients, such as absorptive foliar scales or a velamen radicum. Despite substantial studies on the occurrence, morphology, development and phylogeny of the velamen, most of the available literature is focused on Orchidaceae, making current knowledge on velamen clearly biased. A recent publication firmly established that velamina are common in Anthurium species. Thus, this study provides further insights by describing velamen morphological characteristics of Anthurium species and classifying them into different velamen types. Furthermore, we investigate if the different velamen morphological traits are clade‐specific and phylogenetically conserved within the genus.Using SEM, we performed a morphological study on 89 Anthurium species, describing six micromorphological traits of velamen and exodermis, following traits used to classify Orchidaceae velamen by Porembski & Barthlott (1988).We distinguished nine velamen types, including two that are unique to Anthurium and not similar to any type found in Orchidaceae. Comparing velamen morphology within the phylogenetic tree of Anthurium revealed clear phylogenetic signals.This study provides detailed morphological descriptions among 89 species of Anthurium from the Araceae, and substantially broadens our knowledge of this tissue. However, velamen function has been even less studied, with hardly anything known about functional significance of having secondary cell wall thickening and perforations on velamen cell walls. Therefore, a logical next step would be to connect these anatomical features to their functions. [ABSTRACT FROM AUTHOR]

A foundational concept in ecology is the positive relationship between habitat heterogeneity and species diversity. Epiphytes demonstrate microhabitat specialization to particular areas within a tree; thus, epiphyte communities are potentially influenced by the structural heterogeneity of host trees. We evaluated the relationship between structural features of Acer macrophyllum and epiphyte distributions and abundance in a temperate rainforest in Washington, USA. Epiphytes and structural features of three Acer macrophyllum trees were systematically surveyed using the point-intercept method from the base to the crown and on three branches for each tree. Rarefied species richness increased with structural richness. Species richness along the trunk differed significantly among types of structural features (i.e., broken branches, burls, holes, rivets, branches, and trunks); broken branches had the highest species richness and branches had the lowest, followed by trunks. Rarefied species richness increased with height and peaked at 12 m, but the relationship between structural diversity and height was not significant. The species that occurred on branches were different to those that occurred on trunks, and species composition varied significantly among trunk features. The high structural diversity in northern temperate rainforest trees influenced the fine-scale distribution of nonvascular epiphytes and may explain their coexistence in tree crowns. [ABSTRACT FROM AUTHOR]

The presence or absence of lichens serves as an indicator of the condition of an ecosystem and the degree to which it is contaminated by various agents, such as agrochemicals and metals. Evaluating the use of lichens as bioindicators of agrochemical contamination could provide a more comprehensive perspective of current contamination levels. Monitoring was conducted over a 4-month period in two study areas: one was a well-conserved area contaminated by metals, and the other was an area surrounded by agricultural crops contaminated by agrochemicals. Data on the presence and abundance of lichens in each study area were recorded at 10 monitoring points, a procedure that was repeated 16 times (every 15 days), and concentrations of heavy metals and "organophosphate" agrochemicals in the lichens collected were measured by means of Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-OES) and Gas Chromatography (GC), respectively. Generalized linear mixed models were used to assess abundance and richness, while general linear mixed models were used to attain Shannon diversity and Simpson dominance indices. Moreover, a multivariate analysis was performed in order to compare the lichen communities in both areas. The results indicated differences between the area contaminated by metals and that contaminated by agrochemicals in terms of abundance and Simpson's dominance index, while no differences were found in the case of the richness and diversity models. The PERMANOVA analysis additionally showed differences between the lichen communities in the two areas. The results also demonstrated that Canoparmelia caroliniana bioaccumulated metals in both areas. The levels of barium, cadmium, and sodium were higher in the area contaminated by metals, while concentrations of chromium and copper were higher in the area contaminated by agrochemicals. Finally, the concentrations of agrochemicals were higher in the area contaminated by agrochemicals and included toxic substances such as Methylparathion and Parathion, which are prohibited in Ecuador. In conclusion, this research underscores the importance of lichens as precise indicators of environmental health and contamination by agrochemicals and metals. [ABSTRACT FROM AUTHOR]

Climate change is conjectured to endanger tropical species, particularly in biodiverse montane regions, but accurate estimates of extinction risk are limited by a lack of empirical data demonstrating tropical species' sensitivity to climate. To fill this gap, studies could match high-quality distribution data with multi-year transplant experiments. Here, we conduct field surveys of epiphyte distributions on three mountains in Central America and perform reciprocal transplant experiments on one mountain across sites that varied in elevation, temperature and aridity. We find that most species are unable to survive outside of their narrow elevational distributions. Additionally, our findings suggest starkly different outcomes from temperature conditions expected by 2100 under different climate change scenarios. Under temperatures associated with low-emission scenarios, most tropical montane epiphyte species will survive, but under emission scenarios that are moderately high, 5-36% of our study species may go extinct and 10-55% of populations may be lost. Using a test of tropical species' climate tolerances from a large field experiment, paired with detailed species distribution data across multiple mountains, our work strengthens earlier conjecture about risks of wide-spread extinctions from climate change in tropical montane ecosystems. Epiphytic plants are a highly biodiverse group of tropical species at high risk of extinction from climate change. In this study, a multi-year transplant experiment, paired with distributional surveys in Central America, shows that many of these species may not survive projected changes in climate, providing empirical evidence for hypotheses raised by previous studies. [ABSTRACT FROM AUTHOR]

Species interactions are influenced by changes to the environment, such as seasonal variations in temperature, and human‐driven warming including marine heatwaves (MHWs). Alteration of species interactions, particularly those involving foundation species, can shape ecosystem structure, stability and dynamics. Marine habitats, notably seagrass meadows, are threatened by human‐driven environmental changes including MHWs which have the potential to alter trophic interactions through effects on various community members including seagrasses, epiphytic algae, and epiphytic algae grazers. Here we examined the effects of a simulated marine heatwave (control versus + 4°C) in different seasons and grazer occurrence on seagrass traits, epiphytic algae growth, grazer biomass and grazing rate. We found the season in which the MHW occurred affected the seagrass response and grazer influence. In winter, the MHW had positive effects on seagrass growth and nitrogen content and caused significant decreases in epiphytic algae growth. However, in summer, grazer presence increased seagrass growth and biomass, but growth was reduced by the interaction with the MHW. The season in which the MHW occurred affected the magnitude of change in leaf tissue isotopic values and C:N ratio, with greater changes occurring in summer. Epiphytic algal growth was markedly reduced by the interaction between all three factors, leading to the near lack of epiphyte growth in summer with grazers present under the MHW. Summer was also associated with a greater increase in snail biomass (most notably under MHW conditions), and increased snail grazing rate. From these results, we show that winter MHWs can drive increased growth of seagrasses but minimal impacts on grazers, while in summer increased grazer activity can interact with elevated temperatures from a MHW to increase their algal consumption. By examining responses across multiple trophic levels and distinct seasons, we achieve a more representative and realistic depiction of human‐induced environmental impacts on ecosystems. [ABSTRACT FROM AUTHOR]

Airflow plays a crucial role in plant growth because it supplies CO2, O2, and energy to plants in a plant factory with artificial light (PFAL). Therefore, understanding how various factors affect airflow in and around a plant canopy is essential. In this study, we developed a computational fluid dynamics (CFD) model with realistic plant structures created using structure-from-motion imaging to investigate airflow in and around a plant canopy. The averages of the absolute percentage errors of simulated air velocity in three conditions were 6.7%, 10.1%, 12.7%, respectively. The simulated and measured air velocities agreed well, confirming the accuracy of the developed CFD model. The effects of inflow velocities and plant canopy structures on the airflow in and around the plant canopy were analysed using the validated CFD model. The inflow velocities significantly decreased stagnant zones (from 62.4% to 7.2%) and increased the airflow uniformity in and around the plant canopy. A staggered layout of the plant canopy slightly decreased stagnant zones (from 16.4% to 13.2%) and increased the airflow uniformity. The airflow in and around the plant canopy was further inhibited by a large plant structure. This CFD model provided a basis for improving the airflow status in and around a plant canopy in a PFAL. [ABSTRACT FROM AUTHOR]

The exploration of the diversity of Lycophytes and Ferns of Valparai Range of Anamalai Tiger Reserve, Western Ghats, Tamil Nadu, Southern India resulted in the record for 10 Lycophytes and 93 Ferns of 18 Pteridophyte families. Based on the habitat-forms, there are 51 terrestrial, 15 epiphytes, 16 sciophytes 11 rheophytes and the rest mero- and xerophytes. Eleven out of 103 Pteridophytes showed a very narrow distribution. Among them, Alsophila nilgiriensis (Holttum) R.M.Tryon, Bolbitis semicordata (Baker) Ching, Diplazium travancoricum Bedd., Selaginella tenera (Hook. & Grev.) Spring and S. wightii Hieron. are endemics. Araiostegia hymenophylloides (Blume) Copel. is listed as endangered whereas Athyrium cumingianum (C.Presl) Milde, Bolbitis semicordata, Diplazium travancoricum and Huperzia phyllantha are considered globally threatened. Besides, Athyrium cumingianum (Athyriaceae) is an addition to the Pteridophyte flora of Tamil Nadu state. [ABSTRACT FROM AUTHOR]

Recent reports of airborne sound emissions by plants under drought stress have generated interest, leading to speculative ideas on plant–animal and plant–plant communication. Research on sound production by plants is more than 100 years old, with John Milburn demonstrating in 1966 that these sounds are mainly produced by xylem cavitation events and can be detected with dedicated instruments. Research from 1970 onward has shown that sounds can also be produced by other passive physical processes in plants, and also demonstrated that acoustic emissions can be used to monitor the water status of plants in the field. The hypothesis that sounds produced by plants are informative for insects feeding on stressed plants, or even for neighboring plants, is attractive but still purely speculative to date. A recent study and related commentaries have raised new interest in the phenomenon of ultrasonic sound production by plants exposed to stress, especially drought. While recent technological advancements have allowed the demonstration that these sounds can propagate in the air surrounding plants, we remind readers here that research on sound production by plants is more than 100 years old. The mechanisms and patterns of sound emission from plants subjected to different stress factors are also reasonably understood, thanks to the pioneering work of John Milburn and others. By contrast, experimental evidence for a role of these sounds in plant–animal or plant–plant communication remains lacking and, at present, these ideas remain highly speculative. [ABSTRACT FROM AUTHOR]

Taeniophyllum is a distinct taxon of epiphytic leafless plants in the subtribe Aeridinae of Orchidaceae. The differences in chloroplast genomes between extremely degraded epiphytic leafless orchids and other leafy orchids, as well as their origins and evolution, raise intriguing questions. Therefore, we report the chloroplast genome sequence of Taeniophyllum complanatum, including an extensive comparative analysis with other types of leafless orchids. The chloroplast genome of T. complanatum exhibited a typical quadripartite structure, and its overall structure and gene content were relatively conserved. The entire chloroplast genome was 141,174 bp in length, making it the smallest known chloroplast genome of leafless epiphytic orchids. It encoded a total of 120 genes, including repetitive genes, comprising 74 protein-coding genes, 38 transfer RNA (tRNA) genes, and 8 ribosomal RNA (rRNA) genes. A phylogenetic analysis was conducted on the chloroplast genomes of 43 species belonging to five subfamilies of Orchidaceae. The results showed that the five subfamilies were monophyly, with nearly all segments having a 100% bootstrap value. T. complanatum and Chiloschista were clustered together as a sister group to Phalaenopsis and occupied the highest position in the Epidendroideae. Phylogenetic analysis suggested that T. complanatum and other leafless orchids within the Orchidaceae evolved independently. This study may provide the foundation for research on phylogenetic and structural diversity in leafless epiphytic orchids, thereby enhancing the resources available for chloroplast genome studies in Orchidaceae. [ABSTRACT FROM AUTHOR]

Copyright of Jurnal Paradigma: Jurnal Multidisipliner Mahasiswa Pascasarjana Indonesia is the property of Universitas Gadjah Mada, Himpunan Mahasiswa Pascasarjana, Bidang Jurnal Paradigma and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Phyllosphere-associated microbes can significantly alter host plant fitness, with distinct functions provided by bacteria inhabiting the epiphytic (external surface) vs endophytic niches (internal leaf tissue). Hence, it is important to understand the assembly and stability of these phyllosphere communities, especially in field conditions. Broadly, epiphytic communities should encounter more environmental fluctuations and frequent immigration, whereas endophytic microbiota should face stronger host selection. As a result, we expect greater variability in epiphytic than endophytic communities. We analyzed the structure and stability of leaf phyllosphere microbiota of four traditionally cultivated rice landraces and one commercial variety from northeast India grown in the field for 3 consecutive years, supplemented with opportunistic sampling of eight other landraces. Epiphytic and endophytic bacterial communities shared dominant core genera such as Methylobacterium and Sphingomonas. Consistent with an overall strong environmental effect, both communities varied more across sampling years than across host landraces. Seeds sampled from a focal landrace did not support vertical transmission of phyllosphere bacteria, suggesting that both types of communities are assembled anew each generation. Despite these points of convergence, epiphytic communities had distinct composition and significantly higher microbial load and were more rich, diverse, modular, and unstable than endophytic communities. Finally, focused sampling of one landrace across developmental stages showed that the divergence between the two types of communities arose primarily at the flowering stage. Thus, our results show both convergent and divergent patterns of community assembly and composition in distinct phyllosphere niches in rice, identifying key bacterial genera and host developmental stages that may aid agricultural interventions to increase rice yield.IMPORTANCEPhyllosphere (leaf-associated) microbes significantly impact plant fitness, making it crucial to understand how these communities are assembled and maintained. While many studies have analyzed epiphytic (surface) phyllosphere communities, we have a relatively poor understanding of endophytic communities which colonize the very distinct niche formed inside leaf tissues. We found that across several rice landraces, both communities are largely colonized by the same core genera, indicating divergence at the species level across the two leaf niches and highlighting the need to understand the mechanisms underlying this divergence. Surprisingly, both epiphytic and endophytic communities were only weakly shaped by the host landrace, with a much greater role for environmental factors that likely vary over time. Thus, microbiome-based agricultural interventions for increasing productivity could perhaps be generalized across rice varieties but would need to account for the temporal instability of the microbiota. Our results thus highlight the importance of data sets such as ours—with extensive sampling across landraces and years—for understanding phyllosphere microbiota and their applications in the field.

IntroductionEpiphytic plants are abundant in rainforests and often serve as traps for litter and dust falling from the canopy. As it accumulates, this material can form nutrient rich soils, which are likely involved in local nutrient cycling and ecological processes.MethodsTo explore spatial and temporal variation in the influence of suspended soils on local nutrient cycles, we compared the physical, chemical and biological properties of suspended soils from the locally-dominant epiphytic Bird’s nest fern (Asplenium nidus L.) to those of three types of forest floor soils (soil collected from upslope, downslope, and underneath the host tree) in a tropical monsoon rainforest in Bawangling National Nature Reserve on Hainan Island, China.ResultsSuspended and forest floor soils were all acidic, with suspended soils having much higher organic matter (66.84%) and water content (~ 300%) than forest floor soils. Suspended soils contained significantly more available nitrogen, phosphorous, and potassium and had much higher urease, cellulase, and catalase activities, indicating that they harbored diverse microbial communities with higher decomposition and biomineralization activity.DiscussionPhysicochemical traits of suspended soil and soil collected from under the host tree were significantly more similar in the rainy season than in the dry season, suggesting that suspended soils may contribute to local nutrient cycling as they are flushed out of epiphytic plants and enrich stemflow and forest floor soils.ConclusionThus, suspended soils play a role in local nutrient cycling, especially during the rainy season. This study provides empirical support for the seasonality and heterogeneity of forest floor soil enrichment by suspended soils in tropical monsoon rainforests.

Plant epiphytic microorganisms have established a unique symbiotic relationship with plants, which has a significant impact on their growth, immune defense, and environmental adaptation. However, the impact of fertilization methods on the epiphytic microbial community and their correlation with the yield and quality of medicinal plant was still unclear. In current study, we conducted a field fertilization experiment and analyzed the composition of epiphytic bacterial and fungal communities employing high throughput sequencing data in different organs (roots, stems, and leaves) of Salvia miltiorrhiza, as well as their correlation with plant growth. The results showed that fertilization significantly affected the active ingredients and hormone content, soil physicochemical properties, and the composition of epiphytic microbial communities. After fertilization, the plant surface was enriched with a core microbial community mainly composed of bacteria from Firmicutes, Proteobacteria, and Actinobacteria, as well as fungi from Zygomycota and Ascomycota. Additionally, plant growth hormones were the principal factors leading to alterations in the epiphytic microbial community of S. miltiorrhiza. Thus, the most effective method of fertilization involved the application of base fertilizer in combination with foliar fertilizer. This study provides a new perspective for studying the correlation between microbial community function and the quality of S. miltiorrhiza, and also provides a theoretical basis for the cultivation and sustainable development of high-quality medicinal plants. [ABSTRACT FROM AUTHOR]

Lichens and bryophytes contribute to regulating the forest microclimate and support ecosystem functions. Exploring the thermal heterogeneity at a trunk-level may help elucidate the effect of thermoregulation of epiphytes. We hypothesized that (i) the thermal patterns of epiphytic communities depend on the microclimatic conditions of the surrounding atmosphere and (ii) the thermal heterogeneity at a trunk-level may in turn depend on functional traits of epiphytic communities, such as thallus colour and growth form. We carried out two measurement sessions under contrasting microclimatic conditions (wet vs. dry). Using a thermal camera, we acquired infra-red (IR) images of 50 trees during the same time period under the contrasting wet and dry conditions. Results showed significant differences in thermal characteristics of the trees when contrasting wet with dry conditions and that colour and growth form were significantly associated with changes in thermal patterns at the trunk-level. The study highlights the importance of understanding the thermoregulatory processes of epiphytic communities. [ABSTRACT FROM AUTHOR]

Fungi are ubiquitous and metabolically versatile. Their dispersion has important scientific, environmental, health, and economic implications. They can be dispersed through the air by the aerosolization of near surfaces or transported from distant sources. Here, we tested the contribution of local (scale of meters) versus regional (kilometers) sources by analyzing an airborne fungal community by ITS sequencing around a copper mine in the North of Chile. The mine was the regional source, whereas the soil and vegetal detritus were the local sources at each point. The airborne community was highly homogeneous at ca. 2000 km2, impeding the detection of regional or local contributions. Ascomycota was the dominant phylum in the three communities. Soil and vegetal detritus communities had lower alpha diversity, but some taxa had abundance patterns related to the distance from the mine and altitude. On the contrary, the air was compositionally even and unrelated to environmental or spatial factors, except for altitude. The presence of plant pathogens in the air suggests that other distant sources contribute to this region's airborne fungal community and reinforces the complexity of tracking the sources of air microbial communities in a real world where several natural and human activities coexist. [ABSTRACT FROM AUTHOR]

Copyright of Caldasia is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hemiepiphytes have captured the attention of biologists since they seemingly hold clues to the evolution of epiphytes themselves. Hemiepiphytes are known to occur sporadically in the leptosporangiate ferns, but our understanding of their evolution remains limited by the relatively small number of detailed observations. This study adds to our knowledge by documenting seven species previously assumed to be holoepiphytes. This finding was based on fieldwork conducted in the Baining Mountains of Papua New Guinea that resulted in 319 collections representing 206 species. Approximately 3% of these species were hemiepiphytes: Asplenium acrobryum, A. amboinense, A. scandens, A. scolpendropsis, Crepidomanes aphlebioides, Leptochilus macrophyllus, and Sphaerostephanos scandens. All started growth as low-trunk epiphytes, and later, as larger climbing plants, exhibited strongly dimorphic roots consisting of short clasping ones that affixed the rhizome to the trunks and long feeding roots that entered the soil. Most of the seven hemiepiphyte species that we found exhibited distichous phyllotaxy and dorsiventrally flattened rhizomes, suggesting morphological convergence associated with this habit in four families. These new records suggest that large hemiepiphytic clades occur in Asplenium and Leptochilus. Our observations expand the geographic and taxonomic breadth of hemiepiphytic ferns, provide a baseline estimate of their diversity within a tropical flora, and offer morphological and phylogenetic clues to uncover additional records. [ABSTRACT FROM AUTHOR]

β‐diversity patterns (the compositional variations across sites) and their drivers are the major concerns of biodiversity research and conservation practices, whereas such information remains scarce for vascular epiphytes, especially in tropical forest communities. This study aimed to reveal the pattern and driving process of the compositional variations of vascular epiphytes in a tropical cloud forest on Hainan island, southern China, and their differences from those of terrestrial woody plants. To this end, we quantified their between‐habitat compositional variations and distinguished the underlying components of β‐diversity (nestedness and turnover). We then examined the relative roles of niche‐based and neutral processes in driving the compositional variations by using a null model approach. Our results showed that the between‐habitat compositional variations were significant for both plant assemblages and stronger in vascular epiphytes than in terrestrial woody plants. The turnover component of β‐diversity was significantly stronger in terrestrial woody plants, accounting for 73.16–80.08% of the variations. By contrast, the nestedness component was significantly stronger in vascular epiphytes and characterized 46.82–67.5% of the variations. Besides, the compositional variations of both plant assemblages, especially terrestrial woody plants, were generally poorly fitted by the simulated niche‐based scenarios but well fitted by the simulated neutral scenarios. Overall, the compositional variations of both plant assemblages were significant and mainly due to dispersal limitation, albeit to varying degrees. Hence, further studies of these plant assemblages at local scales should not be ideologically limited to the niche‐based framework. Moreover, the stronger nestedness observed in vascular epiphytes suggests the greater importance of prioritizing conservation efforts in the species‐rich habitats for these plants. [ABSTRACT FROM AUTHOR]

The condenser's rejected heat in a vapour compression refrigeration system when thrown into the surrounding air results in its thermal pollution and gets wasted, while it has the potential to be recovered. Another major targeted concern is freshwater scarcity which is faced by the population in many areas. Addressing these difficulties, a double-stage integrated humidification-dehumidification and air conditioning system that recovers the condenser's waste heat and is assembled in a novel duct architecture is proposed. The obtained results of the developed model are established using the experimental data. The analysis explores the outcomes of the integrated system and investigates the influences of saline water temperature, humidifier efficiency, ambient temperature, and relative humidity on the output and performance metrics. The system provides air conditioning of 31.410 kJ and desalination of 65.020 mL from a unit volume of air using 0.661 kW of power and mitigates the environmental impact of existing technology. The coefficient of energy performance, cooling performance, gained output ratio, and exergy efficiency at the specified working situations are 0.958, 1.320, 6.809, and 2.701 %, respectively. A litre of freshwater costs $ 0.0068486. [ABSTRACT FROM AUTHOR]

The tolerance against air pollution in plants depends on the nature of air particles and gases. This study was carried out to determine chemical composition of indoor dust and to assess its impact on the biochemical properties of foliage of Ficus elastica in two households with different characteristics of Delhi (India). The dustfall fluxe data of major cations and anions were analyzed to understand the spatial variations in the chemical composition and sources of the deposited particles onto the foliage. The fluxes of anionic species (SO42− + NO3−) were higher at MH (industrial) site as compared to the DH (residential) site. The physiological response of F. elastica was investigated by studying the biochemical constituents, i.e., ascorbic acid, soluble sugars, carotenoids, and chlorophyll a and b, in foliage and variations with respect to dustfall fluxes of anionic species (SO42− + NO3−) in the households. Higher (SO42− + NO3−) fluxes had noticeable impacts on biochemical constituents of F. elastica indicating indoor air pollution stress. Chemistry of dust particles showed influences from indoor and outdoor anthropogenic activities. The morphological effects of dustfall deposition on the foliage were also studied using SEM–EDX. Indoor plants can serve as a platform to capture dust particles and plant responses are influenced by the chemical composition of deposited dust. [ABSTRACT FROM AUTHOR]

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Dendrobium is an epiphytic herb plant with neuroprotective, gastroprotective, anti-inflammatory, and immunomodulatory effects. It is often found attached to tree trunks or rocks. With the development of the dendrobium industry, numerous epiphytic patterns exist, such as crushed stone, stump, and sawdust. The study of metabolites and endophytes of D. nobile under different epiphytic patterns, which revealed the effects of epiphytic patterns on D. nobile from the perspectives of metabolomics and microbiology, is of great significance for the healthy development of D. nobile. Methods: In the study, the D. nobile under five epiphytic patterns grown in the same environment were selected. The metabolites were investigated by widely targeted metabolomics, and the endophytes were sequenced using highthroughput sequencing methods. Then, a correlation analysis between the different metabolites and endophytes was performed. Results: A total of 1,032 metabolites were annotated in D. nobile. There are more flavonoids and phenolic acids accumulated on the epiphytic pattern of Danxia stone, whereas the accumulation of lipids on the other epiphytic patterns and 16 differential metabolites was screened out. The endophyte composition of D. nobile was dominated by Proteobacteria, Actinomycetes, unidentified bacteria, Firmicutes, and Cyanobacteria. For endophytic fungi, Basidiomycota and Ascomycota were the dominant phyla of D. nobile. The relative abundance of Spirosoma, Nocardioides, and Arrhenia in the Danxia stone was significantly higher than that of other epiphytic patterns. According to correlation analysis, we found a significant correlation between differential metabolites and Spirosoma, Nocardioides, and Arrheni. Discussion: This study confirmed that Dendrobium quality was affected by its epiphytic patterns and revealed its possible causes from a microbiological point of view. [ABSTRACT FROM AUTHOR]

Despite the high diversity of vascular epiphytes (VE) reported in Peru, there is no updated checklist that is in line with the new taxonomic delimitations and the new concepts of epiphytes. In this study, we update the list of VE in Peru, based on a bibliographic search and visits to local herbaria. Species names were updated according to the World Flora Online, their presence in the EpiList was confirmed, as well as their altitudinal distribution and distribution by department, risk category, and endemism. Finally, the epiphyte coefficient was estimated. We found 2462 species, belonging to 18 orders, 25 families, and 249 genera. The families with the highest richness were Orchidaceae (1606), Bromeliaceae (201), and Piperaceae (139 spp.); 85% of the species were in the EpiList (2088 spp.). The department with the highest richness was Amazonas (709) and the lowest were Ica and Tacna (2 spp.). The altitudinal range with the highest richness is between 1501 - 2000 m (649); 689 species are endemic and 220 are in some risk category; the epiphyte quotient is 13.12. This update represents an approximate 40% increase, positioning Peru as the third country with the highest VE diversity. A more comprehensive list was obtained, in line with the concept of epiphytism, highlighting the need to include 384 species in the EpiList, which would help complement the global list of VE worldwide. [ABSTRACT FROM AUTHOR]

Introduction. Although in all proven cases of carnivory in plants the relevant species are in the Angiospermae, it has been posited that this phenomenon occurs in two genera of liverworts, Colura and Pleurozia. The suggested occurence of zoophagy in these groups is largely based on their trap-like water sacs, leaf modifications, and the positive results of 'feeding' experiments; however, no evidence of nitrogen uptake has been presented. Methods. We measured δ13C, δ15N, %C and %N in Pleurozia acinosa (Mitt.) Trevis. from tropical montane forests in Vietnam, and in representatives from several reference plant groups, both carnivorous and non-carnivorous, and including epiphytes and terrestrial plants. Key results and conclusions. δ13C values in Pleurozia acinosa were significantly higher than in all other groups of plants studied. However, δ15N was significantly lower in P. acinosa than in both groups of true carnivorous plants, and it did not differ from that in non-carnivorous vascular epiphytes and phorophyte trees, being even lower than in other epiphytic bryophytes. Thus, our results do not support the suggestion of carnivory in the genus Pleurozia. [ABSTRACT FROM AUTHOR]

Orchids (Phalaenopsis spp.) growing in tropical and subtropical regions are epiphytes. As such, they grow on trees with the root system utilised to anchor themselves to tree branches. These roots are highly specialised, display a large diameter and are often green, suggesting the ability to carry out photosynthesis. However, the role of photosynthesis in orchid roots is controversial. Orchids that are leafless can photosynthesise in their roots, thus indicating that some orchid roots carry out photosynthesis in a similar manner to leaves. However, the primary site of photosynthesis in orchids are in their leaves, and the roots of epiphytic orchids may mostly conduct internal refixation of respiratory CO2. Besides contributing to the overall carbon metabolism of orchid plants, oxygen produced through root photosynthesis may also be important by alleviating potential root hypoxia. The bulky tissue of most epiphytic orchid roots suggests that oxygen diffusion in these roots can be limited. Here, we demonstrate that the bulky roots of a widely commercially cultivated orchid belonging to the genus Phalaenopsis are hypoxic in the dark. These roots are photosynthetically active and produce oxygen when exposed to light, thus mitigating root hypoxia. Orchid (Phalaenopsis spp.) is a most popular flowering potted plant. However, it has been poorly studied at the physiological and molecular level. The bulky aerial roots of Phalaenopsis have a large diameter and are possibly photosynthetically active. Here, we present evidence demonstrating that root photosynthesis prevents hypoxia in the root tissue. Our results support the existence of hypoxic niches in plant roots and highlight the existence of mechanisms to modulate the intensity of hypoxia. This article belongs to the Collection Flooding Stress and Hypoxic Responses in Plants. [ABSTRACT FROM AUTHOR]

Temperature control with conserving nutrients and irrigation water reduces energy loss, leading to economic and sustainable greenhouse farming. A subirrigation system was applied to strawberry cultivation by placing tubes containing temperature-controlled water (obtained using heat pumps with air or geothermal heat sources) under the soilless substrate of a cultivation container. A ball tap supplied water gravitationally, avoiding the need for a water reservoir, thereby minimizing the volume of water required for heating and cooling. The substrate temperature in the heat pump treatments retained an optimal temperature for growth (averaging 18.4 ℃ in all seasons). The coefficient of performance of the heat pump with the geothermal heat source during heating operations was approximately 1.8 times higher than that with the air heat source. However, the geothermal heat source reduced overall electricity consumption by 14.9% for five months of the experimental period. Production was increased by 21% and 36% in the geothermal and air-source heat pump treatments, respectively, compared to that of the control, owing to the preferable condition of the substrate for strawberry growth. Although salinization of the substrate due to the closed irrigation system may be of concern and damage plant growth, the subirrigation system minimized the loss of water, nutrients, and heat owing to the omission of a reservoir. Furthermore, with minor modifications, the proposed system could be converted to a dual heat pump system to enhance energy use efficiency. [ABSTRACT FROM AUTHOR]

Air pollution is emerging as one of the most important stresses, particularly in urban areas, of both developed and developing countries. It severely affects plant growth and development besides being a health hazard to humans and animals. Delhi has the dubious distinction of being one of the most polluted cities in the world. Incidentally, it is also one of the greenest cities with ongoing programs to increase the already considerable forest cover and biodiversity parks. Plants often act as a sink for airborne pollutants, including particulate matter. Hence it is important to evaluate their efficacy in absorbing pollutants and use the promising species for urban plantation. In the present study, the stress tolerance of four common trees of Delhi (Psidium guajava, Alstonia scholaris, Murraya koenigii, and Moringa oleifera), growing in three areas with varying pollution levels, was estimated by measuring Plant Secondary Metabolites (PSMs: total phenols, flavonoids, alkaloids, and tannins) along with the total chlorophyll content of the leaves. P. guajava showed significant increase in the contents of phenols, tannins, and alkaloids with higher Air Quality Index (AQI). Increased amounts of phenols and flavonoids were observed in A. scholaris, those of phenols and alkaloids in M. koenigii, and only of alkaloids in M. oleifera. There was a decrease in the total chlorophyll content of the leaves of all four species investigated. P. guajava and A. scholaris can be recommended for plantation along the sides of roads with heavy traffic movement. Since PSMs are seen to accumulate as a defense mechanism against air pollution too, as in various abiotic and biotic stresses, they can be used as biomarkers for stress tolerance in plants. [ABSTRACT FROM AUTHOR]

There are a number of rather anecdotal reports of plant growth on power cables in the Americas, but until now there has been no systematic attempt to gauge the geographical extension of this phenomenon nor a documentation of the diversity of species found there. Using observations from the participatory science data platform iNaturalist and the scientific literature, we document almost 700 occurrences of more than 40 species of vascular plants and three lichen species on power cables with a geographical distribution over 7000 km from the southern United States to northern Argentina. Based on these observations we discuss the ecological conditions of plant growth on power cables in terms of climate; elevational distribution; and the morphological, physiological, and life history traits that allow the observed set of species to thrive on this anthropic structure.

Marine ecosystems are important in discovering novel fungi with interesting metabolites that have shown great potential in pharmaceutical and biotechnological industries. Seagrasses, the sole submerged marine angiosperm, host diverse fungal taxa with mostly unknown metabolic capabilities. They are considered to be one of the least studied marine fungal habitats in the world. This review gathers and analyzes data from studies related to seagrasses-associated fungi, including taxonomy and biogeography, and highlights existing research gaps. The significance of the seagrass–fungal associations remains largely unknown, and current understanding of fungal diversity is limited to specific geographical regions such as the Tropical Atlantic, Mediterranean, and Indo-Pacific. Our survey yielded 29 culture-dependent studies on seagrass-associated endophytic and epiphytic fungi, and 13 miscellaneous studies, as well as 11 meta-studies, with no pathogenic true fungi described. There is a significant opportunity to expand existing studies and conduct multidisciplinary research into novel species and their potential applications, especially from understudied geographical locations. Future research should prioritize high-throughput sequencing and mycobiome studies, utilizing both culture-dependent and -independent approaches to effectively identify novel seagrass-associated fungal taxa.

Mutualisms have driven the evolution of extraordinary structures and behavioural traits, but their impact on traits beyond those directly involved in the interaction remains unclear. We addressed this gap using a highly evolutionarily replicated system – epiphytes in the Rubiaceae forming symbioses with ants. We employed models that allow us to test the influence of discrete mutualistic traits on continuous non‐mutualistic traits. Our findings are consistent with mutualism shaping the pace of morphological evolution, strength of selection and long‐term mean of non‐mutualistic traits in function of mutualistic dependency. While specialised and obligate mutualisms are associated with slower trait change, less intimate, facultative and generalist mutualistic interactions – which are the most common – have a greater impact on non‐mutualistic trait evolution. These results challenge the prevailing notion that mutualisms solely affect the evolution of interaction‐related traits via stabilizing selection and instead demonstrate a broader role for mutualisms in shaping trait evolution. [ABSTRACT FROM AUTHOR]