The systematic significance of floral morphology, nectaries, and nectar concentration in epiphytic cacti of tribes Hylocereeae and Rhipsalideae (Cactaceae)

A long-standing interest in cactus taxonomy has existed since the Linnaean generation, but an appreciation of the reproductive biology of cacti started early in the 1900s. Numerous studies indicate that plant reproductive traits provide valuable systematic information. Despite the extensive reproductive versatility and specializations in breeding systems coupled with the striking floral shapes, the reproductive biology of the Cactaceae has been investigated in approximately 10% of its species. Hence, the systematic value of architectural design and organization of internal floral parts has remained virtually unexplored in the family. This study represents the most extensive survey of flower and nectary morphology in the Cactaceae focusing on tribes Hylocereeae and Rhipsalideae (subfamily Cactoideae). Our objectives were (1) to conduct comparative morphological analyses of flowers and floral nectaries and (2) to compare nectar solute concentration in these two tribes consisting of holo- and semi-epiphytic species. Flower morphology, nectary types, and sugar concentration of nectar have strong taxonomic implications at the tribal, generic and specific levels. Foremost, three types of nectaries were found, namely chamber nectary (with the open and diffuse subtypes), furrow nectary (including the holder nectary subtype), and annular nectary. All Hylocereeae species possess chamber nectaries, in which the nectarial tissue has both trichomes and stomata. The Rhipsalideae are distinguished by two kinds of floral nectaries: furrow and annular, both nectary types with stomata only. The annular nectary type characterizes the genus Rhipsalis. Nectar concentration is another significant taxonomic indicator separating the Hylocereeae and Rhipsalideae and establishing trends linked to nectar sugar concentration and amount of nectar production in relation to flower size. There is an inverse relationship between flower size and amount of nectar production in the smaller Rhipsalideae flowers, in which nectar concentration is more than two-fold higher despite the smaller volume of nectar produced when compared to the large Hylocereeae flowers. Variability of nectary morphology and nectar concentration was also evaluated as potential synapomorphic characters in recent phylogenies of these tribes. In conclusion, our data provide strong evidence of the systematic value of floral nectaries and nectar sugar concentration in the Cactaceae, particularly at different taxonomic levels in the Hylocereeae and Rhipsalideae. © 2013 Perspectives in Plant Ecology, Evolution and Systematics.

Microwave hydrothermal synthesis, characterisation, and catalytic performance of Zn1-xMnxO in cellulose conversion

Wurtzite-type Zn1-xMnxO (x = 0, 0.03, 0.05, 0.07) nanostructures were successfully synthesised using a simple microwave-assisted hydrothermal route and their catalytic properties were investigated in the cellulose conversion. The morphology of the nanocatalysts is dopant-dependent. Pure ZnO presented multi-plate morphology with a flower-like shape of nanometric sizes, while the Zn0.97Mn0.03O sample is formed by nanoplates with the presence of spherical nanoparticles; the Zn0.95Mn0.05O and Zn0.93Mn0.07O samples are mainly formed by nanorods with the presence of a small quantity of spherical nanoparticles. The catalyst without Mn did not show any catalytic activity in the cellulose conversion. The Mn doping promoted an increase in the density of weak acid sites which, according to the catalytic results, favoured promotion of the reaction. © 2013 Institute of Chemistry, Slovak Academy of Sciences.

Relação de custo/benefício na interação entre a aranha Peucetia flava (Oxyopidae) e a planta Rhynchanthera dichotoma (Melastomataceae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeitos indiretos de predadores e de herbívoros florais e foliares no comportamento de visitantes florais e sucesso reprodutivo de Rubus rosifolius

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Componentes quantitativos e qualitativos da dispersão de sementes de Struthanthus flexicaulis (Loranthaceae) em uma área de campo rupestre do sudeste brasileiro

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência da borda e do isolamento na fenologia e no sucesso reprodutivo de Anadenanthera Falcata (Benth.) Speg. (Fabaceae) em uma região de cerrado Stricto Sensu, Itirapina, São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Morfoanatomia dos órgãos reprodutivos e da plântula de Epiphyllum phyllanthus (L.) Haw. (Cactaceae)

Pós-graduação em Ciências Biológicas (Biologia Vegetal) - IBRC

Fenologia e sucesso reprodutivo de Attalea geraensis e Syagrus petraea (Arecaceae) na borda e interior de um fragmento de cerrado

Pós-graduação em Ciências Biológicas (Biologia Vegetal) - IBRC

Floração e frutificação de Myrtaceae de floresta atlântica: limitações ecológicas e filogenéticas

Pós-graduação em Ciências Biológicas (Biologia Vegetal) - IBRC

Produção de biomassa, rendimento e composição do óleo essencial de manjericão (Ocimum basilicum L.) em função de reguladores vegetais

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Adubação nitrogenada da caramboleira para pomar em implantação

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Alterações nutricionais em hortaliças decorrentes de diferentes métodos de cozimento

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

A maior flor do mundo de José Saramago e a educação ambiental na escola

Pós-graduação em Educação para a Ciência - FC

Doses de nitrogênio no desenvolvimento de girassol ornamental (Helianthus annuus L.) de vaso

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Doses de composto orgânico, com e sem fósforo adicionado ao solo, na produção e qualidade de sementes de alface

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)