Reproductive innovations and pulsed rise in plant complexity.

Morphological complexity is a notable feature of multicellular life, although whether it evolves gradually or in early bursts is unclear. Vascular plant reproductive structures, such as flowers, are familiar examples of complex morphology. In this study, we use a simple approach based on the number of part types to analyze changes in complexity over time. We find that reproductive complexity increased in two pulses separated by ~250 million years of stasis, including an initial rise in the Devonian with the radiation of vascular plants and a pronounced increase in the Late Cretaceous that reflects flowering plant diversification. These pulses are associated with innovations that increased functional diversity, suggesting that shifts in complexity are linked to changes in function regardless of whether they occur early or late in the history of vascular plants.

DNA barcoding identifies cryptic animal tool materials.

Some animals fashion tools or constructions out of plant materials to aid foraging, reproduction, self-maintenance, or protection. Their choice of raw materials can affect the structure and properties of the resulting artifacts, with considerable fitness consequences. Documenting animals' material preferences is challenging, however, as manufacture behavior is often difficult to observe directly, and materials may be processed so heavily that they lack identifying features. Here, we use DNA barcoding to identify, from just a few recovered tool specimens, the plant species New Caledonian crows (Corvus moneduloides) use for crafting elaborate hooked stick tools in one of our long-term study populations. The method succeeded where extensive fieldwork using an array of conventional approaches-including targeted observations, camera traps, radio-tracking, bird-mounted video cameras, and behavioral experiments with wild and temporarily captive subjects-had failed. We believe that DNA barcoding will prove useful for investigating many other tool and construction behaviors, helping to unlock significant research potential across a wide range of study systems.

Linking vein properties to leaf biomechanics across 58 woody species from a subtropical forest.

Leaf venations have elements with relatively lower elasticity than other leaf tissue components, which are thought to contribute to leaf biomechanics. A better mechanistic understanding of relationships between vein traits and leaf mechanical properties is essential for ecologically relevant interpretation of leaf structural variations. We investigated 13 major (first to third order) and minor (>third order) vein traits, six leaf mechanical properties and other structural traits across 58 woody species from a subtropical forest to elucidate how vein traits contribute to leaf biomechanics. Across species, vein dry mass density (ρv ), total vein dry mass per leaf area (VMA) and minor vein diameter (VDmin ), but not the lower-order vein density (VLA1•2 ), were positively correlated with leaf force to punch (Fp ) and force to tear (Ft ). Structural equation models showed that ρv and VDmin not only contribute to leaf mechanical properties directly (direct pathway), but also had impacts on leaf biomechanics by influencing leaf thickness and leaf dry mass per area (indirect pathway). Our study demonstrated that vein dry mass density and minor vein diameter are the key vein properties for leaf biomechanics. We also suggest that the mechanical characteristics of venations are potential factors influencing leaf mechanical resistance, structure and leaf economics spectrum.

Man-made soil drainage alters the vegetation structure and woody species distribution in campo de murundus

Campos de murundus work as recharge zones and are important for the maintenance of water resources in Brazilian Cerrado. However, with the expansion of the agricultural frontier, this ecosystem may disappear or suffer high anthropogenic disturbances. The aim of the study was to evaluate the structure and distribution of woody species, after the implantation of artificial drainage channels in campo de murundus, in plots near and distant of the drains in the soil. We sampled woody individuals with ≥ 3 cm diameter at the base, and established 20 permanent plots of 20×50 m, 10 of which were between 0-20 m of the drains (edge) and 10 between 150-200 m distant from the drains (interior), totaling two hectares of survey. We recorded 47 species with total density of 230.5 ind.ha-1 and total basal area of 1.331 m2 ha-1. The diversity index of species was H’ = 3.18. We recorded higher density and basal area in the edge, and differential distribution and occupation of woody species in the microrelief of the murundus. This provides us strong evidence that the drains have altered the vegetation structure, especially in the edge of the remnant campos de murundus turning the vegetation woodier and denser.

Functional diversity and convergence in the evolution of plant reproductive structures.

Background and Aims: Structures that simultaneously perform many functional roles are likely to show a variety of morphological solutions to these demands, and thus probably exhibit high morphological disparity. In contrast, specialization for a few simple functions should result in a more limited suite of morphologies. We explore this idea using lycopsid reproductive structures, which, throughout their history, have performed a limited set of functional roles compared with the reproductive structures of other plant groups such as seed plants. Methods: We scored living and fossil lycopsid taxa for 18 discrete character measurements and several continuous traits, including sporangium size, supporting axis diameter, and strobilus length and width. We used the discrete characters to construct a multivariate morphospace for lycopsid reproductive morphology through time, and the continuous characters to test whether fossil and extant lycopsids show similar patterns of tissue allocation within reproductive structures. Results: Lycopsids occupy similar areas of reproductive morphospace and show similar patterns of tissue allocation over most of their history, alternating between diffuse fertile zones with leaf-like sporophylls and compact strobili with specialized sporophylls that allow sporangia to be closely packed while also protected during their development. Growth habit also plays an important role in lycopsid reproductive evolution, broadly influencing the size and shape of reproductive structures. Conclusions: Lycopsid reproductive structures are primarily specialized for densely packaging sporangia, and are consistent with the idea that performing limited functional roles is associated with reduced morphological disparity. Morphologies similar to lycopsid strobili are also found in other groups with simple, wind-dispersed propagules, suggesting that the same processes occur across plant lineages.

Wood anatomy of Laguncularia racemosa (Combretaceae) in mangrove and transitional forest, Southern Brazil / Anatomía de la madera de Laguncularia racemosa (Combretaceae) en manglar y bosque de transición en el sur de Brasil

Abstract Mangroves represent an environment of great heterogeneity and low diversity of plant species that have structural and physiological adaptations linked to a high salinity environment. Laguncularia racemosa is a typical tree species in mangroves and transitional zones. This study aimed to compare the wood anatomy of L. racemosa (Combretaceae) in two different forests (mangroves and transitional forests), which have different soil conditions. For this, we obtained wood and soil samples in March 2016. We analyzed soil nutritional contents in one 15 cm deep soil sample per forest type. In addition, we selected five mangrove trees in each formation for wood anatomy analysis and took one wood sample per individual, per area. We prepared histological slides and separated materials following standard methods for wood anatomy studies. Soil analysis showed that mangrove soils had higher phosphorus, potassium and calcium contents. The transitional soil had lower pore water salinity and soil pH, probably due to high aluminum levels. Anatomical attributes differed between different forest populations. In the different wood aspects evaluated, we obtained higher values in mangrove individuals when compared to the transitional forest population: vessel elements length (375.79 mm), tangential vessels diameter (75.85 mm), frequency of vessels (11.90 mm) and fiber length (889.89 mm). Moreover, parenchyma rays height was larger in the samples of the transitional forest (392.80 mm), while the mangrove population presented wider rays (29.38 mm). The structure of the secondary xylem in the studied species apparently responds to edaphic parameters and shows variations that allow it to adjust to the environmental conditions. The population of the transitional forest showed a secondary xylem that invests more in protection than the mangrove population. Rev. Biol. Trop. 66(2): 647-657. Epub 2018 June 01.

Resumen Los manglares representan un ambiente de gran heterogeneidad y baja diversidad de especies vegetales que tienen adaptaciones estructurales y fisiológicas ligadas a un ambiente de alta salinidad. Laguncularia racemosa es una especie de árbol típico en los manglares y en zonas de transición. El objetivo de este estudio fue comparar la anatomía de la madera de L. racemosa (Combretaceae) en dos bosques distintos (manglares y bosques de transición) que tienen diferentes condiciones edáficas. Para esto se obtuvieron muestras de madera y suelo en marzo 2016. Se analizaron los contenidos nutricionales de una muestra de suelo de 15 cm de espesor por tipo de bosque. Además, se seleccionaron cinco árboles de mangle en cada formación para el análisis de la anatomía de la madera y se tomó una muestra de cada individuo por área. Se prepararon láminas histológicas y se separaron los materiales siguiendo métodos convencionales para estudios de anatomía de la madera. El análisis del suelo mostró que en el manglar hay mayor contenido de fósforo, potasio y calcio. El suelo del bosque de transición tiene menor salinidad del agua capilar y pH del suelo, probablemente debido a los altos niveles de aluminio. Los atributos anatómicos difirieron entre las distintas poblaciones de bosque. En los distintos aspectos de la madera evaluados, se obtuvieron valores más altos en los individuos del manglar comparados con los de la población del bosque de transición: longitud de los elementos de los vasos (375.79 mm), diámetro de los vasos tangenciales (75.85 mm), frecuencia de vasos (11.90 mm) y longitud de la fibra (889.89 mm). Además, la altura de los rayos de parénquima fue mayor en las muestras del bosque de transición (392.80 mm) mientras que la población de manglar presentó rayos más anchos (29.38 mm). La estructura del xilema secundario en la especie estudiada aparentemente responde a los parámetros edáficos y muestra variaciones que le permiten adecuarse a las condiciones ambientales. La población del bosque de transición mostró un xilema secundario que invierte más en protección que la población del manglar.

Developmental programmes in the evolution of Equisetum reproductive morphology: a hierarchical modularity hypothesis.

Background: The origin of the Equisetum strobilus has long been debated and the fossil record has played an important role in these discussions. The paradigm underlying these debates has been the perspective of the shoot as node-internode alternation, with sporangiophores attached at nodes. However, fossils historically excluded from these discussions (e.g. Cruciaetheca and Peltotheca ) exhibit reproductive morphologies that suggest attachment of sporangiophores along internodes, challenging traditional views. This has rekindled discussions around the evolution of the Equisetum strobilus, but lack of mechanistic explanations has led discussions to a stalemate. Scope: A shift of focus from the node-internode view to a perspective emphasizing the phytomer as a modular unit of the shoot, frees the debate of homology constraints on the nature of the sporangiophore and inspires a mechanism-based hypothesis for the evolution of the strobilus. The hypothesis, drawing on data from developmental anatomy, regulatory mechanisms and the fossil record, rests on two tenets: (1) the equisetalean shoot grows by combined activity of the apical meristem, laying down the phytomer pattern, and intercalary meristems responsible for internode elongation; and (2) activation of reproductive growth programmes in the intercalary meristem produces sporangiophore whorls along internodes. Conclusions: Hierarchical expression of regulatory modules responsible for (1) transition to reproductive growth; (2) determinacy of apical growth; and (3) node-internode differentiation within phytomers, can explain reproductive morphologies illustrated by Cruciaetheca (module 1 only), Peltotheca (modules 1 and 2) and Equisetum (all three modules). This model has implications - testable by studies of the fossil record, phylogeny and development - for directionality in the evolution of reproductive morphology ( Cruciaetheca - Peltotheca - Equisetum ) and for the homology of the Equisetum stobilus. Furthermore, this model implies that sporangiophore development is independent of node-internode identity, suggesting that the sporangiophore represents the expression of an ancestral euphyllophyte developmental module that pre-dates the evolution of leaves.

Anatomically preserved "strobili" and leaves from the Permian of China (Dorsalistachyaceae, fam. nov.) broaden knowledge of Noeggerathiales and constrain their possible taxonomic affinities.

PREMISE OF THE STUDY: Noeggerathiales are an extinct group of heterosporous shrubs and trees that were widespread and diverse during the Pennsylvanian-Permian Epochs (323-252 Ma) but are of controversial taxonomic affinity. Groups proposed as close relatives include leptosporangiate ferns, sphenopsids, progymnosperms, or the extant eusporangiate fern Tmesipteris. Previously identified noeggerathialeans lacked anatomical preservation, limiting taxonomic comparisons to their external morphology and spore structure. We here document from the upper Permian of China the first anatomically preserved noeggerathialeans, which enhance the perceived distinctiveness of the group and better indicate its systematic affinity. METHODS: We describe in detail the newly discovered, anatomically preserved heterosporous strobilus Dorsalistachya quadrisegmentorum, gen. et sp. nov., and redescribe its suspected foliar correlate, the pinnate leaf Plagiozamites oblongifolius. KEY RESULTS: Plagiozamites possesses an omega (Ω)-shaped vascular trace and prominent cortical secretory cavities-a distinctive anatomical organization that is echoed in the newly discovered strobili. Dorsalistachya strobili bear highly dissected sporophylls alternately in two vertical rows, suggesting that they are homologs of leaf pinnae. If so, the "strobilus" is strictly a pseudostrobilus and consists of sporangium-bearing units that are one hierarchical level below true sporophylls. The "sporophylls" bear four microsporangia on the lower (abaxial) surface, occasionally interspersed with short longitudinal rows of megasporangia. A single functional megaspore develops within each winged megasporangium, suggesting adaptation for dispersal as a single unit. CONCLUSIONS: Dorsalistachya presents a unique combination of reproductive features that amply justifies establishment of a new family, Dorsalistachyaceae. Noeggerathiales represent a distinct taxonomic Order of free-sporing plants that most resembles early-divergent eusporangiate ferns and the more derived among the extinct progymnosperms. By the early Permian, noeggerathialeans had attained levels of reproductive sophistication similar to the most derived among the Paleozoic sphenophytes and lycophytes, but their heterosporous life history may have contributed to their extinction during the Triassic climatic aridification.

Macro optical projection tomography for large scale 3D imaging of plant structures and gene activity.

Optical projection tomography (OPT) is a well-established method for visualising gene activity in plants and animals. However, a limitation of conventional OPT is that the specimen upper size limit precludes its application to larger structures. To address this problem we constructed a macro version called Macro OPT (M-OPT). We apply M-OPT to 3D live imaging of gene activity in growing whole plants and to visualise structural morphology in large optically cleared plant and insect specimens up to 60 mm tall and 45 mm deep. We also show how M-OPT can be used to image gene expression domains in 3D within fixed tissue and to visualise gene activity in 3D in clones of growing young whole Arabidopsis plants. A further application of M-OPT is to visualise plant-insect interactions. Thus M-OPT provides an effective 3D imaging platform that allows the study of gene activity, internal plant structures and plant-insect interactions at a macroscopic scale.

A robust, high-throughput method for computing maize ear, cob, and kernel attributes automatically from images.

Grain yield of the maize plant depends on the sizes, shapes, and numbers of ears and the kernels they bear. An automated pipeline that can measure these components of yield from easily-obtained digital images is needed to advance our understanding of this globally important crop. Here we present three custom algorithms designed to compute such yield components automatically from digital images acquired by a low-cost platform. One algorithm determines the average space each kernel occupies along the cob axis using a sliding-window Fourier transform analysis of image intensity features. A second counts individual kernels removed from ears, including those in clusters. A third measures each kernel's major and minor axis after a Bayesian analysis of contour points identifies the kernel tip. Dimensionless ear and kernel shape traits that may interrelate yield components are measured by principal components analysis of contour point sets. Increased objectivity and speed compared to typical manual methods are achieved without loss of accuracy as evidenced by high correlations with ground truth measurements and simulated data. Millimeter-scale differences among ear, cob, and kernel traits that ranged more than 2.5-fold across a diverse group of inbred maize lines were resolved. This system for measuring maize ear, cob, and kernel attributes is being used by multiple research groups as an automated Web service running on community high-throughput computing and distributed data storage infrastructure. Users may create their own workflow using the source code that is staged for download on a public repository.

Hierarchical structures of cactus spines that aid in the directional movement of dew droplets.

Three species of cactus whose spines act as dew harvesters were chosen for this study: Copiapoa cinerea var. haseltoniana, Mammillaria columbiana subsp. yucatanensis and Parodia mammulosa and compared with Ferocactus wislizenii whose spines do not perform as dew harvesters. Time-lapse snapshots of C. cinerea showed movement of dew droplets from spine tips to their base, even against gravity. Spines emanating from one of the areoles of C. cinerea were submerged in water laced with fluorescent nanoparticles and this particular areole with its spines and a small area of stem was removed and imaged. These images clearly showed that fluorescent water had moved into the stem of the plant. Lines of vascular bundles radiating inwards from the surface areoles (from where the spines emanate) to the core of the stem were detected using magnetic resonance imaging, with the exception of F. wislizenii that does not harvest dew on its spines. Spine microstructures were examined using SEM images and surface roughness measurements (Ra and Rz) taken of the spines of C. cinerea It was found that a roughness gradient created by tapered microgrooves existed that could potentially direct surface water from a spine tip to its base.This article is part of the themed issue 'Bioinspired hierarchically structured surfaces for green science'.

Morphology, ontogeny and structure of the stipular nectaries in Caamembeca spectabilis (Polygalaceae) / Morfologia, ontogenia e estrutura dos nectários estipulares em Caamembeca spectabilis (Polygalaceae)

Nodal glands are found in one third of the Polygalaceae genera and have valuable taxonomic, ecological and evolutionary significance. In Brazil, they occur in five of the eleven genera already registered. However, there is still a controversy regarding the origin of these structures. The objective of this study was to characterize the morphology and the origin of nodal glands inCaamembeca spectabilis, in order to increase the structural and functional knowledge of these glands in the genera. Samples of nodal regions were collected, fixed and processed according to the methods of light microscopy and electron scanning. Ants were observed and identified along the stem axis. The glucose in exudate allows us to classify these glands as extrafloral nectaries. They are located in pairs on the nodal region. However, its origin is in the leaf trace. In the longitudinal section, the nectaries were present in the apex of cells with anticlinal walls impregnated with suberin, which represents the first record for the family. In this region there is also the formation of a hole by lysis. The secretory tissue is surrounded by phloem. Xylem vessels were observed only on the basis of the nectary, where there are also idioblasts with crystals in druse type. We have studied the ontogeny of the glands nodal in Caamembeca spectabilis and unveiled that these glands are linked to the leaves as stipular nectaries. In addition, the new findings presented here may add support for the understanding of morphology and anatomy of nodal glands in Caamembeca.

Glândulas nodais são encontradas em um terço dos gêneros de Polygalaceae e possuem grande importância taxonômica, ecológica e evolutiva. No Brasil, ocorrem em cinco, dos onze gêneros já registrados. Contudo, ainda há controvérsias quanto à origem dessas estruturas. O objetivo deste trabalho foi caracterizar a morfologia e a origem das glândulas nodais em Caamembeca spectabilis, visando ampliar o conhecimento estrutural e funcional dessas glândulas no gênero. Amostras das regiões nodais foram coletadas, fixadas e processadas segundo os métodos em microscopia de luz e eletrônica de varredura. Formigas foram observadas e identificadas ao longo do eixo caulinar. A glicose no exsudato permite tratar as glândulas como nectários extraflorais. Esses estão localizados aos pares na região nodal. Porém, sua origem ocorre no traço foliar. Os nectários, em secção longitudinal, apresentam as células do ápice com paredes anticlinais impregnadas com suberina, sendo este o primeiro registro para a família. Nessa região também ocorre a formação de um orifício por lise. O tecido secretor do nectário é circundado pelo floema. Vasos de xilema foram observados apenas na base do nectário, onde também ocorrem idioblastos com cristais do tipo drusas. Dessa forma, este estudo confirma a trajetória ontogenética das glândulas nodais em C. spectabilis, as quais, de fato, estão ligadas às folhas, como nectários estipulares. Além de apresentar dados inéditos que auxiliam a compreensão morfológica e anatômica das mesmas em Caamembeca.

Quantitative trait locus analysis for pod- and kernel-related traits in the cultivated peanut (Arachis hypogaea L.).

BACKGROUND: The cultivated peanut (Arachis hypogaea L.) is an important oil and food crop in the world. Pod- and kernel-related traits are direct factors involved in determining the yield of the peanut. However, the genetic basis underlying pod- and kernel-related traits in the peanut remained largely unknown, which hampered the improvement of peanut through marker-assisted selection. To understand the genetic basis underlying pod- and kernel-related traits in the peanut and provide more useful information for marker-assisted breeding, we conducted quantitative trait locus (QTL) analysis for pod length and width and seed length and width by use of two F2:3 populations derived from cultivar Fuchuan Dahuasheng × ICG 6375 (FI population) and cultivar Xuhua 13 × cultivar Zhonghua 6 (XZ population) in this study. RESULTS: Two genetic maps containing 347 and 228 polymorphic markers were constructed for FI and XZ populations respectively. In total, 39 QTLs explaining 1.25-26.11% of the phenotypic variations were detected in two populations. For the FI population, 26 QTLs were detected between the two environments, among which twelve were not mapped before. For the XZ population, thirteen QTLs were detected, among which eight were not reported before. One QTL for pod width was repeatedly mapped between the two populations. CONCLUSION: The QTL analyses for pod length and width and seed length and width were conducted in this study using two mapping populations. Novel QTLs were identified, which included two for pod length, four for pod width, five for seed length and one for seed width in the FI population, and three for pod length, three for pod width and two for seed width in the XZ population. Our results will be helpful for improving pod- and seed-related traits in peanuts through marker-assisted selection.

Morphology, secretion composition, and ecological aspects of stipular colleters in Rubiaceae species from tropical forest and savanna.

Colleters are secretory structures that produce and release mucilage or a mucilage-resin mixture protecting meristems and young structures against desiccation, herbivores, and pathogens. The secretions may vary in colleters of same or different types, indicating that the functionality of colleters may be more specific than previously thought. In this study, we compared 17 Rubiaceae species from savanna and forest environment focusing on colleter secretions and its ecological role. First, we evaluated the morphology, distribution, and histochemistry of stipular colleters using light and scanning electron microscopy. Additionally, we investigated the phenology, microclimate, and the proportion of damaged apices in the savanna and forest species. We recorded standard-type colleters, variable in distribution and size, in 14 of the 17 studied species. The secretion varied from predominantly hydrophilic, mixed to predominantly lipophilic. During the budding period, secretion covered the vegetative apices. Savanna species had a prevalence of lipid secretion in habitats with higher luminosity, which had a lower proportion of damaged apices. In contrast, forest species occurred in habitats with lower luminosity and had a higher proportion of damaged apices, in general with the absence of lipids in the colleters. These results highlight that colleters with similar morphology clearly differed in secretions among species, especially between species from savanna and forest, in which the colleters appear potentially associated with protection against irradiation in savanna, but not in the forest environment.

Structure and distribution of glandular trichomes in three species of Bignoniaceae / Estrutura e distribuição de tricomas glandulares em três espécies da família Bignoniaceae

Glandular trichomes play a major role in the morphological characterization of the Bignoniaceae. Due to their great diversity of forms and functions, this study aimed to inventory the glandular trichomes present in the aerial vegetative axis of Amphilophium magnoliifolium, Martinella obovata and Stizophyllum riparium, analyze their structure and register the participation of ants in these plants. Fresh samples from the nodal region, petiole and from medium to apical regions of the leaflet blade were fixed and processed according to usual methods in light and scanning electron microscopies. The glandular trichomes found were: peltate, capitate, stipitate, and patelliform/cupular. Peltate trichomes are the most abundant ones and present the most uniform distribution. Patelliform/cupular trichomes occur at specific regions, such as prophylls, leaflet blade and nodal regions. Martinella obovata is the only species that presents capitate and stipitate trichomes, which are widely distributed along the entire aerial vegetative axis. Ants were found in all species, mainly at nodal regions. The occurrence of the capitate-type trichome is reported for the first time to the genus.

Tricomas glandulares desempenham papel importante na caracterização morfológica de Bignoniaceae e, devido à grande diversidade de formas e funções que esses tricomas apresentam, o objetivo desse estudo foi inventariar os tricomas glandulares presentes no eixo vegetativo aéreo de Amphilophium magnoliifolium, Martinella obovata. e Stizophyllum riparium, bem como analisar sua estrutura e registrar a participação de formigas nessas espécies. Amostras frescas da região mediana à apical das lâmina foliolar, pecíolo e nó foram fixadas e processadas de acordo com os métodos usuais para microscopia de luz e eletrônica de varredura. Os tricomas glandulares encontrados nas espécies foram: peltados, capitados, estipitados e pateliformes/cupuliformes. Dentre esses tipos o mais abundante foi o tricoma peltado, apresentando também uma distribuição mais uniforme que os demais. Os tricomas pateliformes/cupuliformes estavam em regiões mais específicas, como profilos, lâmina foliolar e na região nodal. Martinella obovata foi a única espécie que apresentou os tricomas capitados e estipitados, amplamente distribuídos ao longo de todo eixo vegetativo aéreo. Em todas as espécies foram encontradas formigas, principalmente nas regiões nodais. A ocorrência do tricoma capitado é relatada pela primeira vez para o gênero.

Automated interpretation of 3D laserscanned point clouds for plant organ segmentation.

BACKGROUND: Plant organ segmentation from 3D point clouds is a relevant task for plant phenotyping and plant growth observation. Automated solutions are required to increase the efficiency of recent high-throughput plant phenotyping pipelines. However, plant geometrical properties vary with time, among observation scales and different plant types. The main objective of the present research is to develop a fully automated, fast and reliable data driven approach for plant organ segmentation. RESULTS: The automated segmentation of plant organs using unsupervised, clustering methods is crucial in cases where the goal is to get fast insights into the data or no labeled data is available or costly to achieve. For this we propose and compare data driven approaches that are easy-to-realize and make the use of standard algorithms possible. Since normalized histograms, acquired from 3D point clouds, can be seen as samples from a probability simplex, we propose to map the data from the simplex space into Euclidean space using Aitchisons log ratio transformation, or into the positive quadrant of the unit sphere using square root transformation. This, in turn, paves the way to a wide range of commonly used analysis techniques that are based on measuring the similarities between data points using Euclidean distance. We investigate the performance of the resulting approaches in the practical context of grouping 3D point clouds and demonstrate empirically that they lead to clustering results with high accuracy for monocotyledonous and dicotyledonous plant species with diverse shoot architecture. CONCLUSION: An automated segmentation of 3D point clouds is demonstrated in the present work. Within seconds first insights into plant data can be deviated - even from non-labelled data. This approach is applicable to different plant species with high accuracy. The analysis cascade can be implemented in future high-throughput phenotyping scenarios and will support the evaluation of the performance of different plant genotypes exposed to stress or in different environmental scenarios.

Evolution of the staminode in a representative sample of Scrophularia and its role as nectar safeguard in three widespread species.

Approximately 30% of the genera of Scrophulariaceae s.str. have a staminode, which is the remnant of a sterile stamen. However, there are no studies of the functionality or evolutionary pattern of staminodes in that family. This paper investigates three Scrophularia species with different staminode sizes to determine if the staminode safeguards nectar from dilution by rainwater and if it influences pollinator behavior. We also study staminode evolution and ancestral state reconstruction onto a phylogeny containing 71 species and subspecies with four different staminode developmental stages: tiny, large, enormous, and absent. The results showed that large staminodes did not hinder nectar collection or modify pollinator-visiting time but acted as a barrier to reduce rainwater entry. The latter reduced the dilution of nectar, which did not occur with tiny staminodes. The phylogenetic study revealed that the ancestral state in the genus corresponds with the presence of a large staminode vs. the tiny and enormous staminodes that are considered as derived. The complete disappearance of the staminode has occurred independently at least twice. Events occurred that increased or reduced the staminode size in one of the clades (Clade II), which includes species of sect. Caninae; most of these events occurred during the Pleistocene (0.6-2.7 Ma).

Water Transport Properties of the Grape Pedicel during Fruit Development: Insights into Xylem Anatomy and Function Using Microtomography.

Xylem flow of water into fruits declines during fruit development, and the literature indicates a corresponding increase in hydraulic resistance in the pedicel. However, it is unknown how pedicel hydraulics change developmentally in relation to xylem anatomy and function. In this study on grape (Vitis vinifera), we determined pedicel hydraulic conductivity (kh) from pressure-flow relationships using hydrostatic and osmotic forces and investigated xylem anatomy and function using fluorescent light microscopy and x-ray computed microtomography. Hydrostatic kh (xylem pathway) was consistently 4 orders of magnitude greater than osmotic kh (intracellular pathway), but both declined before veraison by approximately 40% and substantially over fruit development. Hydrostatic kh declined most gradually for low (less than 0.08 MPa) pressures and for water inflow and outflow conditions. Specific kh (per xylem area) decreased in a similar fashion to kh despite substantial increases in xylem area. X-ray computed microtomography images provided direct evidence that losses in pedicel kh were associated with blockages in vessel elements, whereas air embolisms were negligible. However, vessel elements were interconnected and some remained continuous postveraison, suggesting that across the grape pedicel, a xylem pathway of reduced kh remains functional late into berry ripening.

Estudo farmacobotânico de partes aéreas vegetativas de aroeira-vermelha (Schinus terebinthifolius Raddi, Anacardiaceae) / Pharmacobotanical study of the aerial parts of Brazilian pepper (Schinus terebinthifolius Raddi)

Schinus terebinthifolius Raddi (Anacardiaceae), conhecida como aroeira-vermelha é uma espécie nativa do Brasil, perenifólia e pioneira, sendo muito utilizada para combater diversas doenças, pois apresenta, entre outras, propriedades anti-inflamatórias e cicatrizantes. O objetivo desta pesquisa foi realizar um estudo morfoanatômico do caule e da folha de S. terebinthifolius, descrevendo a organização dos tecidos e suas possíveis variações. As análises macro e microscópicas foram realizadas com material selecionado de partes vegetativas de um espécime localizado na cidade de Campina Grande - PB. A aroeira-vermelha é um vegetal arbóreo e dióico, que apresenta caule cilíndrico e simpodial, com casca rugosa e estriada. A folha é perene, alterna, coriácea e composta. As análises microscópicas evidenciaram epiderme caulinar e foliar uniestratificadas, exceto na face adaxial da folha, que é bisseriada. No caule e no pecíolo são visualizados muitos tricomas tectores unicelulares, curtos, cônicos e agudos no ápice. Encontram-se canais secretores arredondados e bem desenvolvidos na região do floema em todos os órgãos estudados, bem como cutícula revestindo as células epidérmicas e grande quantidade de drusas de oxalato de cálcio. Os feixes vasculares são circundados por células esclerenquimáticas e apresentam o floema seguido por xilema helicoidal bem desenvolvido. No caule, pecíolo e nervura central da folha, o xilema é interno e o floema, externo. A aroeira-vermelha apresenta alguns aspectos estruturais característicos de plantas xerófilas, como camada múltipla da epiderme da face adaxial foliar, que protegem o mesofilo de excessiva dessecação; presença de cutícula espessa e grande quantidade de pêlos e de estômatos; além de sistema vascular bem desenvolvido, com abundância de esclerênquima, dando sustentação ao feixe.

Schinus terebinthifolius Raddi (Anacardiaceae), popularly known as Brazilian pepper, is an evergreen, pioneer and indigenous plant from Brazil, and it is used to combat various diseases, as it presents anti-inflammatory and wound healing properties. The aim of this research was to study the morpho-anatomical features of the stem and leaf of S. terebinthifolius, describing the organization of the tissues and their variations. The macroscopic and microscopic analyses were performed with material selected from vegetative parts of a specimen collected in the city of Campina Grande - state of Paraíba, Brazil. The Brazilian pepper is a dioecious plant with cylindrical and sympodial stem and rough and striated bark. The leaves are evergreen, alternate, leathery and compound. The microscopic analysis showed uniseriate epidermis in the stem and leaf, except in the adaxial leaf, which is biseriate. In the stem and petiole, many unicellular, short, conical tector trichomes with acute apex are observed. In the phloem of all studied organs, we found rounded and well-developed secretory ducts, as well as cuticle covering the epidermal cells and a large amount of calcium oxalate druses. The vascular bundles are surrounded by sclerenchyma cells and present phloem followed by well-developed spiral xylem. In the stem, petiole and leaf's central vein, the xylem is internal and the phloem is external. The Brazilian pepper has some structural features characteristic of xerophilous plants, such as multiple layers of the epidermis in adaxial leaf, which protects the mesophyll from excessive drying, thick cuticle and a large quantity of hairs and stomata, well-developed vascular system with plenty of sclerenchyma, giving support to the bundle.