Plant field guides are portable reference books or digital tools designed to help various users identify plant species in a given area and find out about their morphology, ecology and usage. We present Botascopia (botascopia.inria.fr), a combination of digital tools that automatically produce low-tech field guides in the form of printed paper booklets containing species description sheets associated with an identification key. These are analogous to floras adapted to local ecosystems, such as gardens, parks, school yards or campuses. Botascopia contains a participatory knowledge base with detailed descriptions of plant species. It uses computational languages to express different perspectives on plants held by expert botanists and novice observers, for example, and the translations between them. This setup therefore contributes to addressing the usual challenge of balancing precise vocabulary with making botanical knowledge accessible beyond expert communities. We tested this approach during botanical field sessions with diverse audiences, providing them with personalised, automatically generated printed booklets. This experiment explores how combining low- and high-tech approaches can contribute to the study of the relationships between technology, humans, and plants in the Anthropocene.
The fate of Uranium former mining sites is a real environmental issue because mining may have altered the radioactive background and polluted the surrounding biotopes even after the closure of the mines. The Rophin mine (France) was operated by the French Atomic Energy Commission (CEA) from 1949 to 1957. Downstream of the mine site lies a wetland that bears clear witness to the site's history. Notably, a layer of white clay is present within the upper 10 cm of the wetland soil, providing evidence of the period of active mining. The aim of this study is to investigate the impact of uranium mining at the Rophin mine on aquatic biocenoses via the diachronic analysis of diatom communities. To achieve this objective, a core sample was taken from the Rophin wetland and the diversity and structure of fossil diatom communities were analysed along the stratigraphic layers. Although the Kruskal-Wallis test did not reveal significant differences in species richness among the pre-exploitation, active exploitation, and post-exploitation periods, species enrichment was observed during the exploitation period. Nevertheless, analyses of community structure revealed notable differences among these periods. Diatom species associated with the active mining and post-exploitation phases are predominantly characteristic of inputs from the stream flowing through the site and of the potential acidification of the environment due to mining effluent discharge. The evolution of diatom communities in the Rophin wetland therefore indicates that uranium mining induced a significant reorganization of diatom community structure, despite stable species richness.
This study investigates the scaling relationships between the protective sclerotesta (i.e. the inner sclerotic seed layer) and the internal nutrient reserve within Ginkgo biloba seeds (i.e. the megagametophyte and embryo) to elucidate patterns of resource allocation. Seeds from 12 trees were analyzed by measuring the sclerotesta volume, and the fresh and dry masses of the sclerotesta and its contents (SAC). Scaling exponents and their 95% confidence intervals (CIs) were determined using reduced major axis regression. The results reveal an isometric scaling relationship between SAC dry mass and SAC fresh mass (i.e. the scaling exponent = 1.05 and 95% CI = 0.99-1.13, including unity). In contrast, contents dry mass scaled positively and allometrically with sclerotesta dry mass (i.e. the scaling exponent = 1.13 and 95% CI = 1.07-1.21, exceeding unity). The relationship between sclerotesta volume and SAC dry mass was isometric (i.e. the scaling exponent = 0.99 and 95% CI = 0.92-1.06, including unity). Therefore, although the relationships between SAC dry mass and SAC fresh mass, and between sclerotesta volume and SAC dry mass are isometric, the investment in the nutritive seed core increases disproportionately relative to the protective stony sclerotesta layer (i.e. seed contents increase disproportionately with respect to increasing sclerotesta dry mass), consistent with an adaptive "reproduction-first, defense-later" allocation hypothesis.
Wind dispersal of Liriodendron & times; sino-americanum samaras depends critically on functional traits like mass, projected area, symmetry, and wing loading (mass-to-area ratio). Although wing loading's role has been recognized, its scaling with size/symmetry and symmetry's impact on descent remain unclear. Using 630 samaras, we quantified traits (mass, projected area, bilateral symmetry of 2-D projection) and measured descent time in free-fall experiments. Variation was highest in fresh mass (CV = 30.9%), followed by bilateral symmetry (CV = 29.9%) and projected area (CV = 20.3%), but lowest in descent time (CV = 12.6%). Wing loading was detected as the primary determinant of descent time, showing a strong negative correlation with mean decent time (r = -0.697). Mean descent time decreased with increasing mass and, weakly, with projected area. Mass increased disproportionately faster than area (scaling exponent = 0.643 < 1), diminishing area's buffering effect on descent time reduction. Thus, the disproportionate increase in mass relative to area resulted in higher wing loading and consequently accelerated descent. Bilateral symmetry minimally directly affected descent time but conferred stability via autorotation. This highlights a trade-off between dispersal distance (reduced by faster descent) and seed reserves (enhancing establishment).
Understanding why some plant species become invasive remains a central question in invasion ecology. Two nonexclusive explanations are often proposed: invasion success may result from enhanced growth and reproductive performance or from biochemical novelty that alters plant interactions in new environments. To test these alternatives, we compared growth performance and metabolic profiles of native and non-native populations of Anthemis cotula L. grown under common conditions. Morphological traits, including root and shoot length, biomass allocation, and capitula production, did not differ significantly between native and non-native plants, indicating similar growth performance across ranges. In contrast, untargeted metabolomics revealed clear differences in metabolic richness and composition. Non-native plants exhibited a higher number of detected molecular features, particularly in belowground compartments. Root exudates showed the strongest divergence, with non-native plants displaying greater metabolic richness and a distinct compositional profile. Multivariate analysis confirmed significant differentiation in root exudate chemistry, whereas leaves and flowers remained largely conserved. Despite these compositional shifts, Hill diversity and evenness metrics for both unannotated and identified metabolites showed no significant differences between ranges, suggesting a similar overall diversity structure. Annotation revealed largely conserved chemical classes, dominated by flavonoids in above-ground tissues and amino acids in roots, with subtle enrichment of fatty acids, terpenes, and amino acids in non-native root exudates. Overall, our findings indicate that invasion success in A. cotula is associated less with enhanced growth than with targeted reconfiguration of belowground metabolic traits, especially root exudate chemistry, which may support altered rhizosphere interactions in novel environments.
Recent studies have qualitatively inferred pressure forces within inflorescences and flowers from the deformation patterns observed in floral meristems. Here, we aim to develop a quantitative biophysical model to better characterize these pressures. Our phyllotaxis-based model enables the assignment of numerical values to mechanical forces according to the spatial arrangement of neighboring organs, including bracts, bracteoles, and adjacent floral meristems within inflorescences. We parameterized the model across a range of species representing diverse angiosperm families. These include Portulacineae, whose flowers are laterally compressed by two opposing involucral bracts, and Sapindaceae, in which the genus Acer exhibits remarkable diversity in inflorescence architecture, from simple decussate botryoids to complex abracteolate cincinni. In the Faboideae, Astragalus compactus illustrates how a zygomorphic Bauplan can be mechanically deformed by pressure exerted by a subtending leaf. Overall, the model successfully simulates the mechanical pressures inferred from nearly all developmental biology studies addressing this phenomenon.
Melochia L. (Byttnerioideae - Malvaceae) is a pantropical genus comprising approximately 60 species, 24 of which occur in Brazil, including six endemics. Despite recent taxonomic revisions, several Brazilian species still lacked valid typification. To address these issues, we examined more than 2,300 specimens housed in Brazilian herbaria and consulted international virtual collections, with particular emphasis on type material and original protologues. We designate lectotypes for 17 names and propose one new synonym: M. sergipana Monteiro under M. nodiflora Sw. These nomenclatural updates enhance the taxonomic stability of Melochia and provide a robust framework for future systematic and floristic studies of the genus.
This study presents the first report of range expansion of Amaranthus powellii S. Watson, a species native to tropical Central America, in the temperate Kashmir Himalaya, India. Field surveys and sampling were conducted at ten different sites spread across the study region. The species, being globally recognized for its aggressive weediness, has spread into agricultural fields, roadsides, wastelands, and riparian habitats in this Himalayan region. A taxonomic treatment, including detailed macro- and micromorphological descriptions, photographic documentation, and a comparison of diagnostic characters with the closely related species A. hybridus are provided to facilitate its field identification. The findings from multivariate analyses showed significant inter-population variation in key vegetative and reproductive traits, particularly leaf dimensions, inflorescence characteristics, and pigmentation intensity. Further, results from principal component analysis revealed substantial habitat-associated variation in morphological traits across populations. Populations in resource-rich agricultural habitats possess plants with taller height, broader leaves and longer inflorescences, while those in nutrient-poor wastelands showed relatively shorter height and intense anthocyanin pigmentation. Overall, the wide phenotypic variation observed across habitats indicates that A. powellii inhabits a diverse range of ecological conditions in the temperate Kashmir Himalaya. Given its high reproductive output and adaptability, A. powellii poses a potential risk to regional agriculture and biodiversity. Authentic identification using diagnostic traits, as provided by the present study, is essential for early detection and effective weed management. Looking ahead, future studies should focus on its reproductive biology and potential hybridization to better understand its invasive potential.
Shifts in leaf functional traits and their interrelationships are expected to mirror plant ecological strategies throughout successional gradients. However, little is known about how these traits and their correlations vary across ecological scales during succession, particularly in Mediterranean ecosystems. This study examines the variability of leaf functional traits and CSR (Competitor, Stress-tolerant, Ruderal) strategies across and within Phillyrea angustifolia, Pistacia lentiscus, and Quercus coccifera growing in a matorral and a nearby sacred grove, representing contrasting successional stages and environmental conditions. For each species, 10 individuals per site were assessed for two ecophysiological traits (relative chlorophyll content and leaf thickness) and three structural allocation traits (leaf tissue density, specific leaf area, and leaf dry matter content), along with CSR strategies. Trait responses to changes in soil nutrients, light, and water availability during succession were both species- and trait-specific. When considering all species together, trait correlations aligned with those described by the global leaf economic spectrum. Thus, Q. coccifera and P. angustifolia shifted from conservative or stress-tolerant strategies in the matorral, viewed as a regressive successional stage, toward more acquisitive or competitive strategies in the sacred grove, regarded as a climax stage. Structural allocation traits showed high intraspecific variation and inconsistent within-species correlations, making them reliable indicators of local-scale adaptive strategies. In contrast, ecophysiological traits exhibited more stable relationships across scales and were largely driven by interspecific variation, limiting their usefulness for predicting intraspecific responses along local successional gradients.
Acanthocereus is a monophyletic group comprising 16 species with contrasting vegetative morphology, the greatest diversity is found in the Pacific Lowlands in Mexico. Our prior taxonomic studies on the genus revealed a challenge in delimiting A. rosei, owing to its disjunct distribution and incomplete understanding of morphological variation. Also, during field work in the states of Jalisco and Nayarit, we collected specimens of Acanthocereus with a unique combination of characters inconsistent with previously described taxa. We conducted a phylogenetic analysis using three cpDNA sequences and performed a morphological comparison of disjunct populations of A. rosei in Jalisco and Sinaloa, the atypical Acanthocereus specimens, and other sympatric and similar species from western Mexico. Our results identified the disjunct populations of A. rosei, as well as Acanthocereus sp. as independent lineages. Morphological comparison further supported their divergence by a unique combination of characters. Based on this evidence, we propose a description of two new species two new species of Acanthocereus from western Mexico.
Souroubea is a neotropical genus comprising approximately 21 species, predominantly distributed throughout Amazon Rainforest. Several names associated with the genus present nomenclatural inconsistencies, mainly due to typifications and designations proposed by Adrianus Cornelis de Roon, that do not constitute valid publications according to the International Code of Nomenclature for algae, fungi, and plants. These inconsistencies highlight the need to reevaluate the types associated with taxa within the genus. The aim of this study was to establish the correct application of names through the formal designations of lectotypes and epitypes, when appropriate, and to validate names whose previous publication did not comply with the requirements of the ICN. As a result, we present 14 lectotypifications, one epitypification, and the validation of the name Souroubea corallina, thereby contributing to nomenclatural stability and a better understanding of the genus.
The ROX1 gene of Tobacco (Nicotiana tabacum) was originally identified through its elevated expression in cells transformed with oncogene rolB (root locus) from Rhizobium rhizogenes (formerly Agrobacterium rhizogenes). It is known for its role in the development of anthers and filaments. Thus, rolB-induced overexpression of ROX1 has been proposed to contribute to floral abnormalities in tobacco. N. tabacum, which contains the genomes of its ancestral species N. tomentosiformis and N. sylvestris, harbors two closely related ROX1 orthologs -NtoROX1 and NsyROX1. Herein, we investigated the roles of ROX1 and rolB in tobacco floral morphology by analyzing plants with ROX1 overexpression or gene knockout. Tobacco flowers of plants overexpressing NtoROX1 under CaMV 35S promoter (ROX1-OX) were significantly shorter than those of the wild type (WT). Conversely, flowers of ROX1-knockout plants, in which both orthologs were fully disrupted using CRISPR-Cas9 gene editing (ROX1-KO), were larger than those of WT. To assess the effect of rolB on floral morphology in the absence of ROX1, we next generated WT and ROX1-KO plants expressing rolB under CaMV 35S promoter (WT-RolB and ROX1-KO-RolB, respectively). Flowers of WT-RolB plants were markedly shorter than those of WT, with petal, filament, and style lengths reduced to 74%, 67%, and 73%, respectively. Conversely, when compared with ROX1-KO plants, ROX1-KO-RolB flowers exhibited a reduction in petal length to 93% of the original value, whereas filament length was instead increased to 108%. Collectively, these results demonstrate that rolB-induced floral morphological abnormalities are not mediated exclusively by ROX1 but also involve additional rolB-dependent pathways.
