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Anatomical investigations aiming to seek alternative characters for the taxonomy of bamboos are almost exclusively restricted to the leaf blade. Little is known about the anatomical structure of other parts of the leaf, such as the leaf sheath and pseudopetiole. The present paper analyzed the complete structure of foliage leaves, including the foliage leaf blade, foliage leaf sheath, and pseudopetiole of species belonging to the tribes Bambuseae (subtribes Guaduinae, Chusqueinae and Arthrostylidiinae) and Olyreae (subtribe Parianinae) to identify useful characters in the taxonomy of bamboos. We used scanning electron microscopy and light microscopy to describe micromorphological and anatomical features. All species sampled share the following features: foliage leaf blades with uniseriate epidermis; adaxial bulliform cells; mesophyll with arm cells, cavities, and collateral vascular bundles. Intercostal sclerenchyma associated to bulliform cells was observed only in Arthrostylidiinae. Micromorphologically, the shape and distribution of silica bodies, presence, type, and distribution of papillae on the long cells and subsidiary cells, and the presence and distribution of trichomes may be taxonomically informative in different taxonomic levels. We highlight the absence of papillae on the surfaces of foliage leaf blade of Guaduinae since the presence of papillae is considered a putative diagnosis feature supporting the sister relationship of this subtribe with Arthrostylidiinae. We describe the anatomical structure of foliage leaf sheath for the first time for Guaduinae, Chusqueinae and Parianinae. In Guaduinae, we found a unique distribution pattern of silica cells on the abaxial surface of the leaf sheath. Anatomical data about the pseudopetiole structure also were described for the first time in bamboos species; the arrangement of vascular bundles may be taxonomically informative, especially in Guaduinae.

A multi-level study was performed on the vegetative and reproductive organs of Phlomis fruticosa L. (Lamiaceae), cultivated at the G.E. Ghirardi Botanical Garden (Toscolano Maderno, Brescia, Northen Italy). This work is part of the project Ghirardi Botanical Garden, factory of molecules…work in progress, intended to preserve and enhance the plant heritage hosted at the study site. The multidisciplinary research combined four approaches: I) micromorphological, to describe the structures responsible for the productivity of secondary metabolites; II) histochemical, to define the chemical nature of the secretory products by Light Microscopy, Fluorescence Microscopy, and Scanning Electron Microscopy; III) phytochemical, to characterize the Essential Oil obtained from the blooming aerial parts by hydrodistillation with a Clevenger-type apparatus, consequently analysed by Gas Chromatography-Mass Spectrometry; IV) biological, to assess the potential biological activity of the most abundant EO components based on literature data. Overall, P. fruticosa presented non-glandular and glandular trichomes. The former were multicellular stellate or simple uniseriate, the latter capitate belonging to three morphotypes: branched stalked with a one-celled head, simple short-stalked with a one(two)-celled head, simple medium-stalked with a four-celled head. For the first time, the histochemical survey reported digital images showing a predominant terpenes secretion by the branched-stalked and simple medium capitates, while the simple short hairs were responsible for the secretion of mucopolysaccharides and acid polysaccharides. The EO profile revealed 50 compounds and was dominated by sesquiterpene hydrocarbons (51.1 %) and oxygenated sesquiterpenes (33.6 %), with ar-curcumene (24.3 %), caryophyllene oxide (22.5 %) and α-cedrene (12.8 %) as most representative compounds. Finally, based on literature data, antimicrobial, antioxidant, and anti-inflammatory properties were hypothesized.

In the context of Open Science, an original iconographic apparatus was drafted based on these results to make them accessible to the visitors of the G.E. Ghirardi BG, as an opportunity to discover the plant heritage from an unusual perspective.

Fagaceae is an iconic plant family with 1000+ species distributed predominantly in the northern hemisphere. The reproductive ecology of the Fagaceae species is highly complex, and in the past three centuries, understanding the fruit masting strategies, dispersal, pathogen pressure, and storage has enjoyed steady research interest. However, the interrelationship between these factors is surprisingly less explored, undermining how acorns survive the post-dispersal period. The ability of fruits (acorns, nuts) to survive post-dispersal conditions starts during the maturation drying stage. Successful fruit production depends on the maternal environment, with a ‘good fruit production year’ occurring every few years. This phenomenon might out-maneuver predators by providing sufficient numbers to be consumed but still leaving enough for germination. Because most Fagaceae species have desiccation-sensitive (DS) fruits, survival after dispersal is challenging due to frequent dry spells. Fruit size is not phylogenetically conserved within the genus, with the average fruit mass of Castanea being 50 times higher than the desiccation-tolerant genus Fagus. Larger fruit size may be an adaptation in dry areas because prolonged drying continuously desiccates large-sized cotyledons before desiccating embryos. For species adapted to dry environments, synchronizing dispersal with the growing season could be beneficial, but exceptions exist. Many consumers, such as rodents, aid in the dispersal of fruits, but some fruits are killed in the process, especially those predated late. Upon settling on a site, the pericarp protects the embryo to a certain extent; if drying occurs, the cotyledons become the first site of water loss. However, under extreme drying, survival depends on sporadic rainfall, i.e., wet-dry cycle, which aids in maintaining the critical moisture content required by the fruits for survival. Nonetheless, these adaptive mechanisms are challenged by climate change, which affects the maturation, persistence, and seedling establishment of numerous Fagaceae species.

Aspidosperma is one of the most representative genera in Apocynaceae in Brazil, composed of trees or small trees popularly known as perobas. The genus is distributed throughout tropical America, from Mexico to Argentina, with the exception of Chile. It comprises 80 species, 42 of which occur in Brazil, which is the center of diversity for the genus. Aspidosperma triternatum and Aspidosperma quebracho-blanco, name the Aspidosperma sect. Pungentia, section is easily distinguished from the others, even in the vegetative state, by grouping species that have leaves with pungent apexes, unique in the genus. However, A. triternatum and A. quebracho-blanco are difficult to distinguish due to the morphological similarities they present, such as the pungent apex of their whorled leaves and the yellowish white color of their flowers. Therefore, our objective was to develop a study to obtain leaf morphological using the usual methods of microscopy. The most important diagnostic characters useful for delimiting the species were: the number of pairs of secondary veins; the patterns of distance between these and the median and distal region, as well as the reticulation of these veins; the branching of the tertiary veins; the impression of the quaternary veins as well as their development and the shape of the areola; shape of epidermal cells; cuticular ornamentation pattern; types and distribution of trichomes; distribution of stomata; organization and number of cell layers in mesophyll. We have shown from the performed study that the species have remarkable morphological and anatomical differences which made possible a better circumscription of the group.

Ailanthus excelsa Roxb., belongs to the family Simaroubaceae, is a fast-growing multipurpose tree, and used mainly as a source of fodder and shade. It bears male, female, and hermaphrodite flowers on separate plants. It has been observed that male plant has more leaf biomass during April-May in semi-arid regions of India (Jaipur). In its vegetative state, the sex of the tree cannot be identified. The present study has therefore been designed to investigate if there is any difference in male and female plants based on morphological descriptors namely stomata number, stomata length, stomata diameter, trichome number, trichome length, and trichome diameter. 20 plants with male flowers and 20 plants with female flowers have been studied. The data revealed that male plants have lower trichome diameter (11.91µm) than female (14.18 µm) plants. Other parameters do not show any statistically significant difference (P>0.05). The Omnibus Tests of the Model Coefficient obtained for trichome diameter (0.042) is reliable in improving the model, implying that the model is the best fit. To test the validity of this model, the Hosmer and Lemeshow test was performed, and the p-value of chi-square (0.405 > 0.05) indicates that the logistic model obtained above is the best-fit model. Further studies of trichome diameter at the seedling stage and then confirmation of plant sex at maturity level will help in establishing morphological markers in A. excelsa for identification of sex.

Monteverdia species are known for their medicinal properties. However, due to similarities between species, the accurate identification of different species can be cumbersome. The study of morphoanatomy can contribute to the authentication of the species by providing additional information and contributing to the species characterization. Therefore, this work presents the morphoanatomy of the leaves and stems of Monteverdia evonymoides (Reissek) Biral analyzed by optical microscopy, scanning electron microscopy, and histochemical approaches. Through these methods, we were able to determine, morphologically, the analyzed species features large and woody trees; its leaves are simple, distichous, and entire; the leaf margins are fringed; the stipules are caducous, triangular, and rarely persistent; the apex can vary from acute to obtuse, and the leaf blade has no trichomes. The frontal view presents polygonal epidermal cells, anomocytic, anisocytic, and tetracytic stomata that are found on the abaxial surface and are positioned at the same level as the ordinary epidermal cells; the epidermis is uniseriate and covered with a thick cuticle; the mesophyll is dorsiventral; the midrib is biconvex, and below the epidermis is the angular collenchyma, with one collateral bundle in an open arc and two dorsal bundles; in the ground parenchyma, there is a small collateral vascular bundle, with fibers juxtaposed to the phloem. Histochemical reactions were positive for lipophilic, phenolic, and lignified compounds. Among the observed characteristics, the stomatal classification of the leaf and the prominence of the midrib (adaxial surface) in this study help to identify M. evonymoides and may contribute to species taxonomy by comparing it with other species of the genus and quality control studies.

Bird pollination is well-established in New World Bignoniaceae, but studies of species with floral traits suggestive of bird pollination in the Old World are lacking. Here we studied the pollination ecology of Mayodendron igneum to test the prediction of pollination by specialist flower-visiting birds. Observations from multiple sites showed that both the Streaked Spiderhunter (Arachnothera magna) and pollen-collecting bees were floral visitors. However, almost no fruit was produced if birds were excluded, suggesting that bees do not play a role in pollination, and that pollination is performed almost exclusively by birds in this self-incompatible tree. Measurements of floral traits revealed a typical bird pollination syndrome, and the nectar concentration and volume were both within the proposed ranges based on other flowers pollinated by specialist birds. However, the rather low level of sucrose (less than 2 %) in nectar sugar contradicts the expectation for nectar of flowers pollinated by specialist nectar-feeding birds. Although the Streaked Spiderhunter is among the longest-billed flower-visiting birds in Asia, its bill is only 2/3 of the corolla tube in length, suggesting that the bird can extend the tongue to access nectar. This study is the first to experimentally confirm bird pollination in the Old World Bignoniaceae. It also indicates aspects that are possibly characteristic of spiderhunter pollination systems, i.e. high degrees of specialization, unusual nectar sugar composition, and floral tubes much longer than bird bills.

The evolution of complex floral morphology in orchids can be attributed largely to mechanisms that ensure precise placement of pollinaria on the bodies of animal flower visitors. Floral advertisements and rewards also play a key role in selective attraction of animals that are suitable as pollen vectors. Previous studies of the large African orchid genus Disa have demonstrated high levels of pollination system specialization and have identified functions of floral morphology for transfer of pollen, but studies of pollination in members of the tropical clade of Disa sect. Micranthae have been lacking. This clade is characterized by highly unusual floral morphology, including vertical anthers and pronounced spatial separation between a nectar-producing spur located in the centre of the dorsal sepal and the rostellum lobes that serve to attach pollinaria to flower visitors. In a study conducted in central Zambia, I found that the flowers of Disa engleriana are pollinated by large wasps (Eumeninae and Scoliidae) and carpenter bees. These insect groups carry pollinaria near the tip of their abdomen, which contacts the rostellum when the abdomen is tucked under the flower for balance during nectar-feeding. The pollinaria are rigid and project at 90˚ from the underside of the abdomen such that they contact the deeply recessed stigma during subsequent flower visits. This study reveals a new mechanism of pollen transfer in Disa and sheds light on the evolution of the highly complex floral morphology of this large orchid clade

More than two-thirds of the species in Berchemia exhibit remarkable reproductive phenology, characterized by prolonged fruit ripening and the occurrence of overlapping fruit ripening and flowering. However, the underlying reasons for these phenomena remain unknown. Therefore, this study employed routine paraffin section technology, histochemical technique and scanning electron microscopy to investigate embryo sac development, differences between male and hermaphroditic flowers, as well as the overwintering strategy in Berchemia sinica. The findings of this study revealed a significant reduction in pollen viability and the number of pollen grains per flower in hermaphroditic compared to male flowers. Following fertilization, the ovary of hermaphroditic flowers does not undergo significant enlargement but gradually enters the state of zygotic quiescence. Zygotic quiescence prolongation is the main reason for the long reproductive cycle of B. sinica, and it takes approximately 14 months for the entire cycle from flower bud differentiation to fruit ripening to complete. Long reproductive cycle and complex overwintering mechanism exhibited by B. sinica resemble those seen in species belonging to Betulaceae, Fagaceae, Tapisciaceae, and Theaceae, suggesting convergent evolution during Earth's glacial period resulted in similar adaptive structures among these groups delayed fruit ripening leads to overlap between current year's flowers with previous year's fruits. The trade-off between flower and fruit for reproductive resources may have driven evolutionary transition from ancestral hermaphroditism towards androdioecy in Berchemia.

Butterworts (Pinguicula L.) exhibit a widespread and highly discontinuous distribution in the American continents that host 87 species showing a high level of endemism. To increase our understanding of how such biogeographical patterns originated, we searched for areas of endemism and modelled the suitable habitats for three functional groups of species: temperate heterophyllous, tropical heterophyllous and homophyllous, including their respective geographic subgroups. This approach enabled us to analyse potential distribution changes over time, from the Last Interglacial to the present, and to compare range shifts with the current known distribution in the study area. Through an endemicity analysis, we identified three areas of endemism within the Neotropical region, encompassing two centres of endemism: the Antillean subregion and the Mexican Transition Zone. The models we developed demonstrated high accuracy in predicting the suitable habitats for each group (AUC = 0.906–0.982; TSS = 0.682–0.985). Different sets of bioclimatic variables played a significant role in influencing the potential distribution of Pinguicula functional groups, resulting in differential range shifts from the LIG to the present. Temperate heterophyllous and homophyllous species from southeastern North America, the Caribbean and northern South America experienced severe range contraction during the LGM. Conversely, tropical heterophyllous and homophyllous species from northern South America exhibited range expansion from the LGM to the present. Stable suitable habitats identified in Mexico and eastern Cuba throughout the analysed time periods were closely associated with the two centres of endemism, likely serving as refugia. In contrast, other suitable areas displaying climatic stability were not retrieved as current endemic-rich regions. Therefore, these centres of endemism represent key areas for the conservation of Pinguicula diversity in the Americas, as they can promote the survival of lineages under future climatic variations.