Seed dispersal interactions are critical for the persistence of parasitic plants. However, anthropogenic habitat change may alter those interactions. We examined how anthropogenic habitat transformation in an urban area alters frugivore interactions of the hemiparasitic mistletoe Tristerix corymbosus. While Mimus thenca is traditionally recognized as its primary disperser, rapid urbanization and the replacement of native sclerophyllous vegetation by invasive Acacia species have modified these dynamics. Using focal observations and camera traps, we recorded 181 fruit-consumption events. We found that the herbivorous bird Phytotoma rara accounted for 60
The phenylpropanoid pathway leads to the formation of a wide array of secondary metabolites. In this pathway, the Cinnamate 4-hydroxylase (C4H) gene encodes the enzyme catalyzing the second step of hydroxylation of cinnamic acid into p-coumaric acid. Orchids serve as a rich source of metabolites thus making it significant to analyze the C4Hs in orchids. In the present study, two C4H proteins were identified in each of the orchid species under study (Apostasia shenzhenica, Dendrobium catenatum, Phalaenopsis aphrodite, P. equestris, P. lueddemanniana, P. modesta and P. schilleriana) except in Phalaenopsis bellina which had three C4H proteins. Multiple sequence alignment confirmed the presence of five substrate binding sites, the ERR triad, enzymatic active sites, hinge motif and heme–iron binding domain in all the proteins. Motif analysis showed that the motif encapsulating the p450 domain was present in all the proteins. Secondary structure prediction revealed a prevalence of alpha helices and random coils in the identified proteins. Phylogenetic analysis grouped C4H proteins into two clades, representing class I and II. Gene structural analysis showed the presence of two introns and the promoter study of these genes revealed the presence of cis-acting elements regulated by light, abiotic and biotic stress and plant growth and development. Tissue-specific expression profiling of C4H genes showed varied expression patterns in reproductive and vegetative tissues, suggesting diverse roles in growth and development.
Dyckia brevifolia is a riparian bromeliad endemic to southern Brazil. Despite the endangered status of this species, no genomic resources are available to aid conservation initiatives. This study describes the investigation of the genetic diversity and structure of D. brevifolia populations using newly neutral, species-specific nuclear microsatellite markers developed through genome skimming. Genotyping thirty individuals from three populations with nine generated microsatellite markers revealed low levels of allelic and genetic diversity (A = 2.56 and He = 0.39, Ho = 0.19) and high fixation index (f = 0.46), indicating significant inbreeding levels. Principal coordinates analysis suggested the occurrence of gene flow directed by river current, favoring downstream populations, which evidences hydrochorous dispersal of propagules. These primary data using molecular markers provide the basis for designing conservation strategies to ensure the maintenance of gene flow and genetic variability in the fragmented populations of D. brevifolia.
In this study, embryogenic calluses (EC) of Cinnamomum camphora were used as the initial material and control, and somatic embryos (SE) were used as the material to be tested for transcriptome analysis. By analyzing the expression patterns of genes related to lipid anabolism (fatty acid biosynthesis, fatty acid elongation and triacylglycerol synthesis), the energy storage mechanism during somatic embryogenesis was explored. The transcriptome analysis results of somatic embryos and embryogenic calluses in Cinnamomum camphora revealed a total of 80 differentially expressed genes (DEGs) associated with lipid anabolism, including 56 up-regulated genes and 24 down-regulated genes. Among them, the key genes related to the fatty acid biosynthesis pathway were ACC, KASⅠ/Ⅱ/Ⅲ, and FATA/B. The key gene involved in the fatty acid elongation pathway was KCS. The key genes in the triacylglycerol synthesis pathway were GPAT, DGAT, and PDAT. Through comparison, it was found that there were significant differences in the expression of genes related to the three pathways of lipid anabolism, indicating that the activity of lipid anabolic pathways in embryogenic calluses and somatic embryos was different. Fatty acid biosynthesis, fatty acid elongation, and triacylglycerol synthesis were all more active in the somatic embryos. This study, from the perspective of lipid anabolism, provided a reference for researching energy storage during the somatic embryogenesis process of Cinnamomum camphora.
Fire triggers flowering, stimulating and advancing flower production and, consequently, fruiting in some plants of the Cerrado, the Brazilian savanna. Integrated Fire Management (IFM) has been applied in several protected areas in the Cerrado to simulate natural fire regimes. However, its effects on both flowering and fruiting patterns remain underexplored. This study evaluated the impact of IFM on the phenology and abundance of flowers and fruits of Macairea radula, an abundant shrub that produces large quantities of flowers. Sampling was conducted monthly for 12 months in both unburned and low-intensity prescribed-burned areas. Our findings highlight the complex interactions between fire and plants. Prescribed fire anticipated and extended flowering, indicating that M. radula is fire-stimulated but not fire-dependent. However, fire reduced both the fruiting period and fruit abundance, suggesting an effect on initial reproductive stages that did not lead to increased fruit availability over time. These findings underscore the need to monitor phenological processes beyond flowering. Species-specific assessments are essential for understanding the full impact of IFM on plant reproductive strategies and for guiding fire management in fire-prone biodiversity hotspots. From a management perspective, our results also indicate that adjusting the timing of prescribed fires to avoid periods of high reproductive sensitivity may substantially mitigate negative effects on plant reproductive success without compromising the benefits of low-intensity burns.
The critically endangered evergreen tree Elaeocarpus venustus is a specialist of submontane riparian swamps, where it exhibits a singular, synchronous annual phenological cycle driven by climatic cues. Research indicates that its flowering is positively correlated with rainfall but negatively influenced by rising temperatures. While a single individual in a nutrient-rich swamp habitat can command up to 31.8
Palaeobotany can provide insights into the preservation patterns of different plant organs in the fossil record and how diversity was represented across various geographic scales in the Permian palaeoflora. These insights are important for interpreting palaeodiversity and palaeoenvironmental conditions more integratively. Reproductive and vegetative organs may be preserved in systematically different proportions, potentially biasing our understanding of past plant communities and leading to over- or underestimation of diversity depending on the fossils available in different regions, climates, or time intervals. We thus investigate whether vegetative or reproductive elements reported in 37 studies spanning 1945 to 2024 are more abundant in the Permian fossil record and how different geographic scales influence the diversity of these elements. Networks, combined with meta-analyses, were employed to understand the heterogeneity of fossil-taxa composition and certain biogeographic aspects. Our results revealed a higher proportion of vegetative than reproductive parts, with the type of anatomical fragment separating distinct geographic regions at different scales. No evidence of publication bias was detected. Continental-scale analyses favoured vegetative parts, whereas hemisphere-scale patterns favoured reproductive parts. Networks indicated Leiotriletes as a connector taxon and Pecopteris as widely distributed. Antarctica showed the highest palaeobotanical potential, with the greatest diversity of preserved parts. Leaves appeared to increase the taxonomic precision of the recorded fossil-taxa. Arborescent plants may have dominated the physiognomy of milder climates during different Permian epochs. The Late Permian does not appear to have undergone abrupt changes in its palaeofloristic physiognomy when fossil-taxa are considered at the genus level.
Astereae, comprising approximately 252 genera and 3100 species, is the second largest tribe within the family Asteraceae. Members of this tribe are most commonly found in temperate regions. Astereae is considered the sister tribe of Anthemideae. The taxonomy and subtribal classification of the Astereae are challenging and controversial. Consequently, pollen morphology is a practical and reliable tool for studying the systematics of the Astereae due to its conserved features. This study aims to identify and describe the pollen types within Astereae based on pollen features and to investigate the relationships among subtribes, genera and species using these data. The pollen micromorphology of 39 specimens representing 11 genera of Astereae was examined using scanning electron microscopy. Clustering and ordination methods identified three pollen types—Aster, Bellis and Symphyotrichum—among the studied taxa. PCA analysis revealed that the distance between spines was the most important pollen feature for distinguishing the three groups. Therefore, pollen morphology played a reliable role in the delimitation of the studied species within the tribe and identifying the different pollen types. Using the pollen data, the taxonomic problems related to the delimitation between the genera Aster and Erigeron were resolved based on differences in pollen micromorphology. The studied Astereae taxa demonstrated the greatest similarity in pollen features with the tribe Anthemideae, particularly in features such as exine ornamentation and spine size.
Canistrum (Bromeliaceae) comprises 13 species endemic to the Atlantic Forest and is subdivided into two subgenera (Canistrum and Cucullatanthus). This study aimed to characterize the morphology of reproductive structures (pollen and stigma), assess pollen viability and stigma receptivity across all species of the genus, and evaluate the taxonomic, reproductive, and conservation relevance of these characters. Analyses were conducted using light microscopy (with pollen grains prepared by lactic acetolysis) and scanning electron microscopy. Pollen viability was assessed using histochemical tests and in vitro germination assays at three floral stages. Stigma receptivity was evaluated through enzymatic assays. Pollen grains are dispersed as monads and show variation in shape (oblate, suboblate, and oblate-spheroidal), polarity (apolar and subisopolar), amb (circular and elliptical), aperture (pantoporate and biporate), and exine ornamentation, consistently semitectate and reticulate-heterobrochate to foveolate, with differences in lumen structure depending on the presence of granules. The occurrence of distinct pollen types proved informative for infrageneric delimitation within Canistrum. Stigmas are conduplicate-spiral, with stigmatic lobes ranging from crenulate to laciniate, and coloration varying from white to yellow. Pollen viability was high in all species, especially during anthesis, a stage that also showed the highest in vitro germination rates. Stigma receptivity peaked at anthesis and remained high during post-anthesis, indicating synchrony between pollen and stigma and suggesting the absence of dichogamy. Overall, pollen aperture type and exine ornamentation are stable characters of taxonomic value, whereas viability, germination, and receptivity patterns provide insights into reproductive strategies, supporting conservation and reproductive management of endemic and threatened Canistrum species.
This study evaluated the effects of solar UV-B (Ultraviolet-B) radiation on coffee seedlings at different altitudinal ranges in a tropical environment. A field experiment, conducted using a randomized complete block design, tested four coffee varieties—Fayette, Odisha, Koti, and Hangafa—under natural UV-B radiation and UV-B-blocking sheets at altitudes of 1450, 1850, and 2150 m, with three replications. The results revealed that altitude significantly influenced most growth parameters, except for specific leaf area and primary branch girth. The interaction between altitude and coffee variety affected plant height, primary branch length, and internode length (at p < 0.001, 0.01 and 0.05, respectively), with plant height and primary branch length decreasing as altitude increased. Altitude also impacted leaf area and physiological parameters such as photosynthetic rate (Pn) and transpiration rate. In contrast, the interaction of UV-B and altitude influenced stomatal conductance and intercellular CO2 levels. These findings demonstrate that coffee varieties respond differently to solar UV-B radiation at different altitudes. This highlights the need for location-specific coffee breeding/genetic selection/ in tropical environments to address adaptation to climate change, particularly in relation to increased UV radiation.
We investigated the role of Aluminum (Al) as a limiting factor for the development of Borreria latifolia, analyzing morphophysiological changes, subcellular accumulation sites, and its interaction with pH on biomass increment. We evaluated biomass fluctuation under different Al concentrations of 0, 250, 500, and 750 µM, and the combined effect of Al (presence/absence) under pH 3.5, 4.5, or 5.5. The beneficial effects on both root and shoot development were dependent upon both Al concentration and medium pH. The concentration of 750 µM Al at pH 4.5 induced the highest dry mass buildup. In the absence of Al, the pH gradient did not affect plant growth, but the addition of Al (pH 4.5) promoted dry mass increases of 34
Drought is the most prevalent environmental stress in crop production, posing a significant danger to food security. Microorganisms in the crop root zone affect crop growth and development, enhance effective nutrient use, and resist adversity hazards. Our study was to analyze the changes and functional differences of rhizosphere soil communities in sugar beet under drought stress. In this study, the rhizosphere soil of sugar beet were collected and analyzed by high-throughput sequencing and bioinformatics at 7, 14 and 21 days after water control treatment. There were two levels of water control treatment: normal water supply (relative soil water content = 70
Stream macroalgal communities were sampled at 58 sites across four national parks representing highland grasslands in southeastern Brazil. We assessed taxonomic beta diversity and its components (spatial turnover and nestedness), as well as the influence of selected environmental variables. Environmental conditions varied widely among streams from the different parks, reflecting high environmental heterogeneity, a pattern commonly reported for similar ecosystems worldwide. Cyanobacteria predominated in the flora of the four parks (47.4
The interaction between abiotic factors and plant traits is central to ecological strategies and species distribution, especially in environments with climate variability. It is reflected in morphoanatomical and biochemical traits that influence growth and survival. Widely distributed, species-rich families are models for understanding how environmental filters shape plant traits and foster innovation. Bromeliaceae, a diverse Neotropical family, exemplifies this dynamic, bringing together species with multiple habits (epiphytic, rupicolous, saxicolous, and terrestrial) and remarkable morphological diversity. Given Bromeliaceae significance in the Brazilian Atlantic Forest, particularly in high-elevation regions, we investigated environmental parameters potentially influencing trait variation in three widely distributed species: Aechmea vanhoutteana, Pitcairnia carinata, and Quesnelia kautskyi, occurring in distinct areas within Parque Nacional do Caparaó (MG/ES), Brazil. PCA analyses confirmed that temperature, humidity, and light intensity were the primary filters shaping functional trait space, possibly influencing niche differentiation and species coexistence. Aechmea vanhoutteana exhibits a generalist ecological strategy, thriving across all three life habits with minimal morphoanatomical and biochemical content adjustments. Pitcairnia carinata, confined to rocky outcrops, exhibited notable anatomical specializations likely balancing thermal tolerance and water conservation. Quesnelia kautskyi demonstrated the greatest trait variation, particularly between terrestrial and epiphytic individuals, with humidity emerging as the main driver of anatomical and biochemical differences. While morphological traits were relatively stable across conditions and functioned as “effect traits”, anatomical and biochemical traits acted as “response traits”, adjusting dynamically to environmental stimuli. Altogether, the results highlight that morphoanatomical and biochemical plasticity is critical for ecological performance and persistence in heterogeneous montane landscapes. Furthermore, approaches incorporating multiple traits can offer key insights into how environmental pressures potentially drive plant adaptation, specialization, and evolution in Neotropical ecosystems.
The reproductive structures of the family Piperaceae are a subject of debate, primarily because of the high variability in megagametophyte development and the modifications to previous characterizations of final arrangement of the embryo sacs. Information on the reproductive biology and pollination strategies of Peperomia remains limited. This study provides a detailed description of the developmental morphology and floral anatomy of Peperomia bracteata from Pedregal de San Angel, Mexico. We conducted a detailed developmental and anatomical study of P. bracteata inflorescences and flowers using light and scanning electron microscopy with conventional histological and histochemical techniques. Our findings revealed that the flowers are arranged spirally on spikes that mature basipetally. The flowers are perianthless and each is subtended by a bracteole. The androecium consists of two stamens with short, broad filaments, while the gynoecium features a single ovule within a globose ovary, broad style, and capitate stigma. Lipid-secreting osmophores were detected in both the ovary and the style. The embryo sac was tetrasporic and contained 16 nuclei, conforming to the Peperomia-type configuration. This study provides the first comprehensive description of floral morphoanatomy and gametophyte development in a Mexican Peperomia species. Our results provide valuable insights into the structural and embryological diversity of Piperaceae, highlighting the evolutionary relevance of female gametophyte variation and floral specialization in early-diverging angiosperms.
Tuberous roots in monocots exhibit considerable variation in shape and size, yet their development and anatomical diversity remain poorly understood in Commelinaceae. This study investigates the morphological and anatomical diversity of tuberous roots in seven species representing three of the four major lineages in the family—Palisota, Commelineae, and Tradescantieae s.s.—with emphasis on the tuberization patterns. Tuberous root samples from Palisota barteri, Commelina platyphylla, Dichorisandra leucophthalma, D. marantoides, D. radicalis, D. thyrsiflora, and Tradescantia pallida were collected and fixed in FAA50 and embedded in both Historesin and Paraplast. We carried out morphometric analyses, as root diameter, cortical cells number (CCN), vascular parenchyma cell number (VPCN), and phloem area (PA), from transverse sections of tuberous roots, and we revealed two distinct morphological types of tuberous roots: the stalked shaped characterized by having two non-thickened extremities and a thickened median region and the sessile shaped, with thickening uniform along all the root. In general, the dermal system and cortical region on the thickened region of both stalked and sessile shaped roots, do not differ from what was observed in the non-thickened region. However, in the vascular system our results show four anatomical patterns: (1) In the first pattern the parenchyma of the centre of the vascular cylinder in the non-thickened region is not lignified, whereas, in the thickened region, it is composed of lignified cells; (2) In the second pattern, all parenchyma cells of the centre of the vascular cylinder are lignified, both in the non-thickened and in the thickened region; (3) In the third pattern the parenchyma of the centre of the vascular cylinder is composed of non-lignified cells in both regions (thickened and non-thickened); and (4) The last pattern reveals a fragmentation of the vascular system observed only in Dichorisandra, and the parenchyma of the centre of the vascular cylinder in the non-thickened region is lignified, whereas, in the thickened region, it is composed of expanded storage parenchyma. In the cortical region, a protective tissue was observed only in Tradescantia pallida, from subepidermal or outer cortical cells. Bifurcated root hairs were observed in Commelina platyphylla, P. barteri and T. pallida. With the new contributions to the understanding of the structural processes involved in root tuberization in Commelinaceae, we encourage studies using this approach in other Commelinoideae, and especially in other subfamilies as Cartonematoideae.
LEA3 proteins are crucial for plant stress tolerance against drought, salinity, and cold. This review highlights their structure, featuring disordered conformations and conserved motifs like the 11-mer repeat, which enable stress adaptation. LEA3 genes are induced by abiotic stresses and exhibit tissue-specific expression. Functional studies show they protect cells via cryoprotection, metal binding, and biomolecule stabilization. Overexpression enhances stress resilience in transgenic plants. Genome-wide analyses reveal evolutionary diversification linked to stress adaptation. This review consolidates current knowledge on LEA3 proteins, emphasizing their molecular versatility and prospects for biotechnological applications in stress-resilient agriculture.
Ecological restoration is essential to recovering degraded ecosystems and reestablishing fundamental environmental processes such as stability, succession, and resilience. This study evaluated whether the mixed planting of eight native forest species and the facilitator species Baccharis dracunculifolia influences Floristic community composition and diversity indices, phytosociological parameters, patterns of species community composition between treatments, and the effect of overgrowth and light on natural regeneration in areas undergoing ecological restoration. The experiment was conducted at the Canguiri Farm Experimental Station, Paraná, Brazil, using a randomized block design with two treatments and four replicates. Plots of 432 m2 were monitored four and five years after planting (2023–2024). We do not find differences between treatments regarding Floristic composition. The results indicated that both treatments mixed planting (T1) and planting with facilitating species (T2) showed an increase in floristic richness, diversity, and abundance between 2023 and 2024, with T1 maintaining slightly higher values of diversity (Shannon index) and evenness (Pielou index) over time. Baccharis semiserrata and B. dracunculifolia stood out in the phytosociological parameters, being dominant in treatments and years. The PCoA analysis revealed significantly different floristic compositions between treatments in both years. Finally, a negative effect of light was observed on diversity and evenness in T1 in 2024 and on diversity and richness in T2 in 2023.
Gliricidia sepium (Jacq.) Kunth ex Walp has potential to improve ecosystem services and support sustainable agriculture. The aim in this study was to explore anatomical variations affected by planting density to enhance biomass yield and nutritive value in intensive production systems. A randomized block design experiment assessed three planting densities (10,000, 20,000, and 30,000 plants ha −1), focusing on micromorphometric traits, biomass output, bromatological composition, and the correlations between key variables. Leaf micromorphometric analysis indicated that planting density significantly impacts the abaxial epidermal surface, both upper and lower collenchyma, lacunar parenchyma, and the numbers and density of stomata. Notable variations were found in the medullary radius, cortex, and periderm of stems and the periderm and phloem of roots. Total plant height increased linearly with higher planting densities. Among bromatological traits, hemicellulose content showed a decreasing trend as planting density rose. Strong correlations emerged among various micromorphometric, biometric, production, and bromatological variables, signifying an integrated structural and functional response to planting density. These findings indicate that a density of 30,000 plants ha−1 provides an ideal balance between anatomical structure development and functionality, thereby enhancing field productivity and cost-effectiveness. The results show the phenotypic plasticity of G. sepium, underscoring its capability to adapt structurally and functionally to achieve high productivity in intensive planting scenarios. This insight aids in the domestication and sustainable cultivation of the species.
We provide new genetic and spatial data on the conservation of Paepalanthus longiciliatus (≡Coracoralina longiciliata (Trovó) Andrino, Eriocaulaceae), a narrowly distributed species from Goiás, Brazil, officially categorized as Critically Endangered (CR). Despite identifying potential occurrence sites surrounding the type locality, which still harbors a population of a few hundred individuals, efforts to locate new populations were unsuccessful. Most of these potential areas are indeed unprotected private properties. Herbarium searches also failed to yield additional specimens; consequently, the species is known only from three records at the type locality (1996, 2009, and 2024). The species occurs in typical dystrophic cambisoils of the Cerrado, with a clayey-silty texture, generally considered less suitable for large-scale monoculture. However, land-use changes observed over time indicate the transformation of native vegetation into a mosaic of diverse uses, including a paved road, monoculture plantations, and pastures, the latter often involving the use of fire and invasive grasses. Genetic data suggest low genetic diversity and high inbreeding, although the relatively high nucleotide diversity suggests that some genetic variation is still retained. These patterns likely reflect the effects of genetic drift in an isolated species restricted to a small population with limited dispersal capacity. The species’ rhizome and sprouting reproduction mode likely explain its survival under moderate adverse conditions. Given these findings, the species should remain categorized as Critically Endangered. Additional botanical explorations, the implementation of a Private Natural Heritage Reserve (RPPN), and ex-situ conservation techniques are essential efforts to ensure the preservation of this species.
