Resumo em Inglês:

ABSTRACT Grassland ecosystems present patterns of plant-pollinator interactions that may be linked to habitat heterogeneity, plant composition and disturbances. Most studies about plant-pollinator interactions in the Neotropics were conducted in forest, savanna-like, or Andean vegetation. However, the current increase in the number of studies about interactions in grassland vegetation promises a better understanding of the pollination ecology of these landscapes. In this systematic review, we summarised information from 24 articles about plant-pollinator interactions in South Brazilian grasslands. We highlighted patterns of plant-pollinator interactions, indicating their particularities compared to other grassland communities in South America. Bees are important pollinators of many plant species in these grasslands and most plants are visited by more than one group of pollinators. Among the plant species visited by a single pollinator group, most were visited by bees. However, many types of pollinators, plant species, habitats, and regions have, thus far, received little sampling effort. Pollination by groups other than bees, such as nocturnal pollinators, flies, beetles, and birds, is particularly understudied. The information provided in this review summarizes data that could be used to foster more detailed pollination studies to understand the diversification and maintenance of grassland floras of South Brazil.

Resumo em Inglês:

ABSTRACT Humiria balsamifera is an infraspecific complex of high phenotypic variation and widely distributed in northern South America. Leaf traits are traditionally considered the most relevant taxonomic characters for varietal level delimitation in the group. However, substantial phenotypic overlap among vegetative characters complicates taxonomic diagnoses in this complex. The objective of this study was to quantify and analyze phenotypic variation among individuals of the complex at a continental scale using uni- and multivariable analyses to assess whether morphometric analyses detect discontinuities. Secondarily, these quantitative data were used to test whether phenotypic similarity was related to geographic distance. Twenty- five quantitative and 27 qualitative character traits did not overtly reveal a topology corresponding to traditional varietal classification, nor to geographic structure. However, petiole length alone revealed a definitive separation of H. balsamifera var. guianensis (together with another recognized species Humiria wurdackii, and variety H. balsamifera var. laurina) from the rest of the taxa. Our results highlight substantial morphological overlap among vegetative and reproductive characters including those used in identification keys, and no morphological discontinuities suitable for clearly separating taxa within the complex were encountered demonstrating a future need to integrate multiple sources of information, including molecular data, to resolve this complex.

Resumo em Inglês:

ABSTRACT Understanding the factors that affect native plant communities is essential to protect floristic diversity, particularly in Mediterranean agroecosystems. The Chilean Mediterranean-climate area supports high species richness and levels of endemism, and harbors the main fruit production. We investigated whether the richness of native and non-native flora differs between two Mediterranean climate areas of Chile with contrasting rainfall levels in both cultivated and uncultivated habitats. Thirteen fruit farms under conventional management were prospected in the spring of 2015 and of 2016 by sampling in square meter quadrants (N = 3,630). A total of 191 vascular plants were found, 48.2 % of them native, 50.3 % non-native and 1.6 % not identified. Species richness was low in both areas and habitat types. However, there were more native species in uncultivated habitats in the Mediterranean-to-desert transition area than in the mesic Mediterranean area, and the contrary was observed for non-native species. Our results suggest that wetter Mediterranean climate areas are more prone to the establishment of non-native plant species.

Resumo em Inglês:

ABSTRACT The Cerrado represents the largest extension of savanna in South America. It occupies large stretches of central Brazil, being fragmented towards the Northeast, Southeast, and South regions of the country. Examples of disjunct patches of vegetation with savanna physiognomy within the Caatinga can be found in the Chapada Diamantina, the Chapada do Araripe, in small areas of southern Ceará State, and also in the coastal plains. This study recorded the floristic composition of four savannas within the Caatinga in northern Ceará State and evaluated the floristic relationships between these and other savannas, Cerrado and Caatinga sites. Periodic floristic collections recorded 247 species distributed among 162 genera and 55 families. Fifty-seven percent of the recorded species were of herbaceous or sub-shrubby habit, while the majority of the flora was of the therophytic life-form. Biogeographic analyses revealed that the study sites differ from typical Cerrado in flora and life-form spectra and have closer floristic relationships with Caatinga vegetation. The presence of floristic elements from the Cerrado, together with species from the Caatinga, in the study sites allows us to conclude that these savanna enclaves in the Caatinga are composed of a mixed flora with typical elements of these two Brazilian biomes.

Resumo em Inglês:

ABSTRACT There are two homomorphic self-incompatibility (SI) mechanisms among flowering plants - gametophytic self-incompatibility (GSI) and sporophytic self-incompatibility (SSI). Whilst SI has the advantage of promoting outbreeding in natural populations, it can also be a problem for horticulturists and agronomists. Thus, a number of techniques have been successfully employed to break both GSI and SSI, including bud pollination, saline pre-treatment of the stigmas and simply selfing ageing flowers. We applied these three techniques to determine whether they would be effective at breaking SI in Ceiba chodatii, a species with late-acting self-incompatibility (LSI). We self- or cross-pollinated buds ranging from 1-4 days prior to anthesis and checked ageing by selfing or crossing flowers at 1-4 days after the onset of anthesis, with those at four days showing petal wilt. None of the selfed buds or ageing flowers set fruit, unlike the majority of crossed flowers. Likewise, all flowers to which 1 % saline was applied to the stigmas prior to selfing failed to set fruit. We conclude that unlike GSI and SSI, which have pre-zygotic control of self-pollen function, LSI is likely to be immune to these techniques since the focus of rejection occurs after self pollen tubes have reached the ovary.

Resumo em Inglês:

ABSTRACT Rio Turvo State Park (RTSP) is a Conservation Unit located within the Atlantic Forest biome in the Vale do Ribeira region of the State of São Paulo, Brazil. Considering the lack of knowledge regarding its bryoflora, we performed a floristic inventory of RTSP (following the random-walk method), the results of which we report here including discussion of the geographical distribution (Brazil and worldwide), substrate colonization, life forms and reproduction of the species. We found a total of 414 species, which represents 30 % of all known bryophyte species in Brazil. Dioicous species were predominant over monoicous species, the most colonized substrate was tree trunk (40 % of all species) and the predominant life form was mat (47 %), indicating that the floristic composition is influenced by the environmental conditions of the area (high humidity, dense vegetation and shading). Although anthropogenic intervention is present in RTSP, it harbors huge biodiverse potential, since 22 % of the species are rare. Furthermore, 16 new occurrences were recorded for the State of São Paulo. The information provided by this study exalts the importance of this Conservation Unit in the preservation of bryophytes, as well as all the biodiversity of its included ecosystems.

Resumo em Inglês:

ABSTRACT Campinaranas are unique vegetation patches in the Amazonian biome, characterized by white-sand soils with relatively low nutrient content and subject to periodic flooding coupled with fluctuating groundwater levels. This study aimed to produce a synopsis of the bryophyte flora in Campinarana habitats by combining information from the literature with new collections made in the Uatumã Sustainable Development Reserve (Balbina, Central Amazonia), and areas of the middle Uaupés river (São Gabriel da Cachoeira, upper Rio Negro). One hundred and forty-three species were identified among mosses and liverworts, of which 68 are reported for the first time in Campinaranas. The species Frullania rio-janeirensis, Ceratolejeunea filaria, Diplasiolejeunea cobrensis and Bazzania diversicuspis are new records for the state of Amazonas. These results reveal high species richness for Campinaranas and indicate the need for continued study in this underexplored Amazonian habitat. This study emphasizes the importance of carrying out floristic inventories in poorly known environments and of further studies with different approaches, such as ecological, phytogeographic and genetic efforts.

Resumo em Inglês:

ABSTRACT Bacurizeiro (Platonia insignis) is a fruit of the Amazon that, due to anthropic actions, has been suffering serious damage to its genetic diversity. We analyzed the genetic diversity and structure of seven bacurizeiro populations distributed among four Brazilian states and two biomes, the Amazon and Cerrado, based on eight nuclear (ncSSR) and three chloroplast (cpSSR) microsatellite markers. Higher heterozygosity values were found for the Northern populations of Japurá and Marapanim, and the Northeast population of Chapadinha when using ncSSR. Higher diversity indices were also observed for these populations with cpSSR, although higher haplotypic diversity parameters were detected for the two Northern populations. Genetic structure analysis showed the formation of two well defined groups: I - populations from Maranhão and Piauí (Cerrado) and II - populations from Amazonas and Pará (Amazon). Positive and significant correlations were identified between genetic and geographical distances for both ncSSR (r = 0.09; p = 0.0010) and cpSSR (r = 0.11; p = 0.0008), in agreement with the genetic structure analysis. The high genetic structure among populations probably reflects the divergent natural and human selection pressures to which bacurizeiros are subjected in both the Amazon and Cerrado biomes, with higher diversity maintained in the Amazon populations.

Resumo em Inglês:

ABSTRACT Calolisianthus speciosus, an endemic species of cerrado and campos rupestres in Brazil, bears colleters in both the leaf base and sepal. These colleters (leaf and sepal) were anatomically compared to identify differences in their structure and secretion mechanism. Samples of sepals and leaves in different development stages were collected and processed according to standard methodologies for anatomical and ultrastructural studies. Sepal and leaf colleters were anatomically similar, being non-vascularized, sessile or short-stalked and composed of a multicellular secretory head with large intercellular spaces where secretion, with a predominance of protein and polysaccharides, is accumulated. The secretory cells have thin walls, dense cytoplasm with granular endoplasmic reticulum, numerous dictyosomes and mitochondria. The ultrastructural characters are in agreement with the production of mucilaginous/protein secretion. The large secretion-filled vacuole merges with the plasma membrane releasing its contents to the periplasmic space where it remains until release outside of the cell wall, where it is accumulated in intercellular spaces formed by schizogeny. This accumulation generates pressure that promotes the passage of secretion through the external wall and the cuticle of superficial secretory cells of the head of the colleter.

Resumo em Inglês:

ABSTRACT Forest stands in seasonal environments can differ spatially and seasonally in the diversity of fleshy fruits available as resources for fauna. The aim of this study was to quantify spatial and seasonal variation in the richness and abundance of the dominant fleshy-fruited tree species in gallery forests of the Cerrado domain. Tree species composition and abundance were compiled from the literature for 10 gallery forest stands. Data were interpolated and extrapolated by the sample coverage method, using Hill numbers to determine the typical species as well as the most abundant species in each fruiting season. Stands differed in the occurrence of fleshy-fruited tree species and in the number of fleshy-fruited tree individuals. Probabilities for the occurrence of fleshy fruit were similar between in the wet and dry. However, across all stands, species that fruit primarily in the dry season were less common than those that fruit in the wet season. The sharing of fleshy-fruited tree species was low and the most abundant species differed among the studied stands. Fleshy fruits were available all year round and periods of high fruit availability are highly synchronized while periods of low fruit availability were much less so.

Resumo em Inglês:

ABSTRACT A new species of Funastrum is described from Veracruz, Mexico. Although Funastrum saganii sp. nov. is morphologically similar to F. elegans and F. lindenianum, there are differences in leaf and flower morphology and geographic distribution. Descriptions, illustrations and the geographic distribution of this species are provided, and its conservation status discussed. Morphological leaf analysis was performed using geometric morphometrics. This discovery highlights Mexico as center of diversity for the genus Funastrum, with 14 of its 19 species located in the country. This finding is important because it is the first new species of Funastrum to be described from Mexico in 127 years.

Resumo em Inglês:

ABSTRACT Tropical dry forests are among the most threatened vegetation types in the world, exposed to even higher deforestation rates than rainforests. The largest tropical dry forest is the Caatinga, in the semiarid Northeast region of Brazil. Home to many endemic species and genera, the Caatinga has lost half of its original vegetation cover and become highly fragmented. Furthermore, the Caatinga is little protected by conservation units and subject to multiple human pressures. Brazil committed to the Convention of Biological Diversity’s Strategic Plan for Biodiversity 2011 -2020, including the Aichi Biodiversity Targets, requiring protection of 17 % of terrestrial habitats. Using GIS, we quantified the total area of Caatinga encompassed by fully protected and sustainable use reserves. We found that less than 8 % of the Caatinga is legally protected under Brazil’s national nature reserve legislation (SNUC law), and only 1.3 % is in reserves with full legal protection. We show that the geographical distribution of reserves is biased, leaving some regions of the Caatinga with very little protection. We conclude that Brazil has not met international conservation commitments with respect to the Caatinga and, despite a recent expansion of the protected area network, only small and unrepresentative portions of the Caatinga are effectively safeguarded.

Resumo em Inglês:

ABSTRACT The dependence of commercial crops on pollinators is closely related to their reproductive strategies and has direct impacts on production yields. Fruit production of Averrhoa carambola, the star fruit, is highly dependent on bee pollination. This distylous species may exhibit monomorphism associated with self-compatibility, a condition that may influence its degree of dependence on pollinators for fruit set. We evaluated the floral morphology and mating system of A. carambola and their relationships with pollinator dependence in an apparently pin-monomorphic orchard to address the following questions: Is the orchard indeed pin-monomorphic? Is the orchard self-compatible? Are pollination services sufficient to reach maximum productivity? Is fruit set related to the number of visits? We investigated floral morphometrics, mating system, and pollination following standard methods of plant reproduction research. The orchard exhibited pin-monomorphism and self-compatibility. Herkogamy strongly impaired spontaneous self-pollination, emphasizing the relevance of pollinators to crop yield. Considering that Apis mellifera was the only pollinator observed, and that the orchard showed pollen limitation, we recommend the implementation of pollinator management strategies. Additional studies will be needed to assess if the atypical distyly observed here occurs in other situations.

Resumo em Inglês:

ABSTRACT Variegated species are highly appreciated for their unique aesthetics. Although often confused, variegation and chimerism are distinct phenomena. Chimerism can also cause variation in the color of plant organs, but it is a specific type of genetic mosaic. Limited information is available on variegation and chimerism in Orchidaceae. Here, the first record of a wild foliar chimeric mutant for the subtribe Laeliinae (Orchidaceae) is presented. In July 2020, a sterile chimeric individual of Epidendrum cinnabarinum was found and photographed in a fragment of restinga in the Área de Proteção Ambiental das Lagoas e Dunas do Abaeté, a conservation unit in the municipality of Salvador in the state of Bahia, Northeast Brazil. The plant's phenotype is a mosaic of green, cream and yellow striped leaves in different proportions. Leaves on one caulome are distinctly colored, not only on the margins, but also in the central portion. Anatomical and ecophysiological aspects of the chimeric specimen need to be studied. The abundance and persistence of the chimeric variegation in the individual will be monitored while this phenomenon should be more closely examined for the species.