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Premise: To further advance the understanding of the species‐rich, economically and ecologically important angiosperm order Myrtales in the rosid clade, comprising nine families, approximately 400 genera and almost 14,000 species occurring on all continents (except Antarctica), we tested the Angiosperms353 probe kit. Methods: We combined high‐throughput sequencing and target enrichment with the Angiosperms353 probe kit to evaluate a sample of 485 species across 305 genera (76% of all genera in the order). Results: Results provide the most comprehensive phylogenetic hypothesis for the order to date. Relationships at all ranks, such as the relationship of the early‐diverging families, often reflect previous studies, but gene conflict is evident, and relationships previously found to be uncertain often remain so. Technical considerations for processing HTS data are also discussed. Conclusions: High‐throughput sequencing and the Angiosperms353 probe kit are powerful tools for phylogenomic analysis, but better understanding of the genetic data available is required to identify genes and gene trees that account for likely incomplete lineage sorting and/or hybridization events. [ABSTRACT FROM AUTHOR]

The Pantanal is a large and diverse wetland that spans three South American countries including parts of Brazil, Paraguay, and Bolivia. An invasive tree, Vochysia divergens Pohl (commonly known as Cambara), has been expanding throughout the Pantanal for more than four decades forming monospecific stands. Given the rapid and extensive spread of Cambara, and the potential for woody plant invasion to alter soil organic matter and nutrient stocks, we hypothesized that Cambara invasion would significantly increase soil organic matter and nutrient content. To test this hypothesis we sampled the soil, litter, and vegetation of a monospecific Cambara stand, a grassland (campo) stand in the process of Cambara invasion (transitional), and a campo stand free of Cambara during the dry season in July and August of 2009 and 2010 when stands were free from seasonal flooding. Surface (0-10 cm) soil in sites dominated by Cambara had significantly higher soil organic matter (SOM), P, and cation content, and higher cation exchange capacity (CEC), but soil pH and K+ concentration were less coincident with Cambara presence. The variation of soil characteristics was also significantly higher in the transitional site, indicating that the transition from a grassland- to a Cambara-dominated system significantly increased the spatial variability of soil chemistry. These results indicate that Cambara invasion fundamentally alters the C and nutrient storage of Panatanal soils. Future research will investigate if these results are general for Cambara invasion and address mechanisms of how Cambara invasion affects the nutrient cycling and storage of Pantanal soils. [ABSTRACT FROM AUTHOR]

In recent decades, cattle ranchers of the Pantanal of Mato Grosso, Brazil, have pointed to the accelerated spread of several herbaceous and woody plant species that invade natural and artificial pastures (campos). It has been speculated that overgrazing by an increasing number of cattle, lack of grazing in abandoned areas,or large-scale changes in environmental conditions may be the reason for this invasion. This study focuses on ecological and ecophysiological aspects of Vochysia divergens (cambará), a flood-tolerant tree that began spreading in the Pantanal during the last 30 years and is considered a very aggressive invasive plant. The study shows that the spread of cambará can be related to natural multi-years wet periods. During multi-years dry periods the species is reduced by the increasing impact of fires in the Pantanal. This points to the great importance of multi-years climatic events on the vegetation cover of the Pantanal and indicates a very dynamic development in plant communities. [ABSTRACT FROM AUTHOR]

A conspicuous feature of Vochysiaceae flowers is their single fertile stamen. In some genera, the stamen is in front of a petal, whereas in others it is in front of a sepal. This difference has been attributed to two independent reductions, which implies the stamen is not homologous across the family. The observation that genera with an antesepalous stamen have only one petal, whereas those with an antepetalous stamen have three or five petals, led us to the hypothesis that in all genera the stamen arises in an antepetalous position, but that it is displaced during development in single-petaled taxa. We examined developing buds of five genera using scanning electron microscopy and serial sectioning and conclude that the stamen in all genera is fundamentally antepetalous. The stamen is not displaced. The petal, however, appears to be displaced in some genera. Further, the position of the fertile stamen in Erisma has been misinterpreted. We discuss the evolution of the androecium in this family in a phylogenetic context and consider the significance of symmetry and of loss vs. suppression in the development of Vochysiaceae flowers. [ABSTRACT FROM AUTHOR]

Vochysiaceae are divided into two tribes on the basis of ovary structure (superior trilocular or inferior unilocular). The superior trilocular ovary has been considered basal in the family, and the term "pseudomonomerous" was used to indicate the presumed evolutionary derivation of the unilocular condition from the trilocular. However, recent evidence that Vochysiaceae are Myrtalean suggests that the superior ovary may be secondarily derived. In addition, published figures cast doubt on the interpretation of the putatively unilocular ovaries. To understand these features, floral ontogeny and anatomy were examined using scanning electron microscopy and serial sectioning. In all taxa examined, the ovary develops in an epigynous fashion, on a concave floral apex, supporting the hypothesis that the superior ovary is secondarily derived. Subsequent to initiation of the ovary, differential growth results in ovaries that are superior, inferior, or partly inferior in different genera. Sections of floral buds of the two unilocular genera, Erisma and Erismadelphus, show aborted locules in the latter but not in the former. The application of the term "pseudomonomerous" to both genera obscures this significant difference. The position of the placenta in the truly unilocular genus varies among species, suggesting a character transformation series from multilocular through intermediates to truly unilocular. [ABSTRACT FROM AUTHOR]

* Premise of the study: Microsatellite primers were developed to investigate genetic diversity and population structure of Qualea grandiflora, a typical species of the Brazilian cerrado. * Methods and Results: Eight microsatellite loci were isolated using an enrichment cloning protocol. These loci were tested on a population of 110 individuals of Q. grandiflora collected from a cerrado fragment in São Paulo State, Brazil. The loci polymorphism ranges from seven to 19 alleles and the average heterozygosity value is 0.568, while the average polymorphic information content is 0.799. * Conclusions: The developed markers were found to be highly polymorphic, indicating their applicability to studies of population genetic diversity in Q. grandiflora. [ABSTRACT FROM AUTHOR]

Presents an abstract of the study `Phylogeny of the Vochysiaceae: Implications of molecular data for floral evolution,' by Amy Litt, presented during the 1996 Annual Meeting of the Botanical Society of America at the University of Washington in Seattle, Washington.

Presents an abstract of the study `The single fertile stamen of the Vochysiaceae: Derived four times or once?,' by Amy Litt, presented during the 1996 Annual Meeting of the Botanical Society of America at the University of Washington in Seattle, Washington.