RESUMO -O presente trabalho teve como objetivos definir o tipo de substrato e a temperatura mais adequados à germinação de sementes de jenipapo (Genipa americana L.), conhecer a morfologia das sementes e seu desenvolvimento pós-seminal, caracterizando as plântulas normais, o tipo de germinação e os padrões de anormalidade. Para tanto, realizou-se um experimento colocando-se as sementes sobre os seguintes substratos: papel, vermiculita e solo, nas temperaturas constantes de 20°C, 25°C, 30°C, e 35°C e alternada de 20°C-30°C. O delineamento estatístico empregado foi o inteiramente casualizado (5 x 3), com quatro repetições de 50 sementes. Foram analisados os parâmetros germinação normal (%) e velocidade de germinação. Os melhores resultados foram obtidos nas temperaturas constantes de 25°C, 30°C e 35°C, e nos substratos vermiculita e solo.Termos para indexação: plântula, Genipa americana. TEMPERATURE, SUBSTRATE AND POST-SEMINAL DEVELOPMENTABSTRACT -This study aimed to define the best substrate and temperature for germination of genipap (Genipa americana L. -Rubiaceae) seeds, and to describe the morphology of its seeds, postseminal development, normal and abnormal seedlings. The experiment was designed according to a 5 x 3 factorial with constant temperatures of 20°C, 25°C, 30°C and 35°C and alternated 20°C-30°C in filter paper, vermiculite and soil substrates. The following parameters were analyzed: normal percentage germination and speed of germination. The 25°C, 30°C and 35°C temperatures and vermiculite and soil substrates were the best conditions for seed germination.

Pollinators, especially insects, could be influenced by forest fragmentation. The aim of this paper was to examine whether there were differences in 1) the communities of floral visitors; 2) the frequency of visits; and 3) the fruit and seed sets of individuals of Psychotria tenuinervis occurring at anthropogenic edges (AEs), natural edges (NEs), and in the forest interior (FI) in 2 yr of study. In 2002, the total number of flower visits was greater in NE and lower in AE, while no difference among habitats was found in 2003. There were differences among sample plots, within habitats, in both years. Bees were the most frequent visitors of P. tenuinervis flowers, and the introduced honeybee Apis mellifera was the most common species observed. There were no differences in the fruit and seed sets, or in the density of reproductive individuals of P. tenuinervis among habitats. However, in 2002, NE showed the greatest proportion of fruits per flower and AE the smallest. The similarity among the habitats was probably due to the marked variation or heterogeneity among the sample plots and among the plants within the habitats, which may have masked any interhabitat differences. The observed heterogeneity and the likely importance of other factors, such as gaps and the age of the edge, on the fragment studied, could be viewed as important issues for conservation programs. RESUMOPolinizadores, principalmente insetos, podem ser influenciados pela fragmentação florestal. O objetivo deste trabalho foi verificar se existem diferenças: 1) nas comunidades de visitantes florais; 2) na freqüência de suas visitas; e 3) na produção de frutos e sementes de indivíduos de Psychotria tenuinervis localizados em bordas antrópicas (BA), bordas naturais (BN) e no interior do fragmento (IF). Em 2002, ocorreram mais visitas florais em BN e menos em BA, enquanto em 2003, não houve diferença entre os ambientes. Houve diferença entre as parcelas dentro dos ambientes em ambos os anos. Abelhas foram os visitantes florais mais freqüentes de P. tenuinervis, sendo Apis mellifera a espécie mais comum. Não houveram diferenças na produção de frutos e sementes nem na densidade de indivíduos reprodutivos entre os ambientes, apesar de em 2002, BN ter apresentado a maior produção de frutos e BA a menor. Essa similaridade entre os ambientes proavelmente ocorreu devido a grande variação ou heterogeneidade entre as parcelas e entre plantas dentro dos ambientes, que mascarou as diferenças entre ambientes. A indicação dessa heterogeneidade e a provável importância de outros fatores, como clareiras ou idade das bordas, nos fragmentos estudados, podem ser muito importantes para programas de conservação.

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Epiphytes are hyper‐diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non‐vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer‐reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non‐vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non‐vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events.

The morphology of Genipa americana seeds and post-seminal development was studied, and its germination response investigated in relation to storage in water, substrate water volume, osmotic potential and temperature and light regimes. The seeds are flattened and seedlings are phaneroepigeal with leafy cotyledons. Seeds stored in water kept viable for up to 6 mo, but germination and seedling emergence were reduced after 4 mo. Germination was not affected under water-logged conditions, but seedling emergence was reduced at the water volume corresponding to a water column two times deeper than the seeds' mean thickness (70 ml). When seeds were osmotically stressed, a reduction in the rate and germination percentage occurred at −0.2 MPa and germination was drastically inhibited at −0.6 MPa. Seeds germinated in a wide range of temperatures (15–40 °C), with optimum at continuous temperatures of 25 and 30 °C. Light was not required for germination, and no dormancy mechanisms were observed. The seed and seedling morphology and the germinative responses of the species may permit its regeneration in periodically flooded lowland forests and riparian habitats and are probably key factors in explaining the species' wide distribution.

-(Flooding effects in seedlings of Cytharexyllum myrianthum Cham. and Genipa americana L.: responses of two neotropical lowland tree species). Six-month-old seedlings of Cytharexyllum myrianthum and Genipa americana, two common tree species in different flood-prone areas in Brazil, were flooded for up to 90 days to compare their survival and growth responses under these conditions. Seedlings of both species were found to be relatively tolerant to flooding but growth responses changed according to treatment and plant species. Growth of G. americana was reduced by flooding, showing a decrease in root and leaf dry mass, root/shoot ratio and height, without showing any adaptive morphological changes. On the other hand, growth of C. myrianthum seedlings was stimulated under flooding conditions, showing an increase in root dry mass, root/shoot ratio, height, stem diameter and some morphological changes in roots and stems, i.e., development of new roots and stem base hypertrophy. These results could be regarded as an experimental corroboration of the field observations, showing that these species could be indicated for restoration programs of some Neotropical wetlands. RESUMO -(Efeito do alagamento em plântulas de Cytharexyllum myrianthumCham. e Genipa americana L.: respostas de duas espécies arbóreas de planícies neotropicais). Plântulas com seis meses de idade de Cytharexyllum myrianthum e Genipa americana, duas espécies comuns em áreas sujeitas a inundações em diferentes regiões do Brasil, foram submetidas à inundação do solo durante 90 dias visando conhecer suas respostas em relação à sobrevivência e ao crescimento de plântulas. As duas espécies mostraram-se relativamente tolerantes à inundação, embora as respostas de crescimento variem em função do tratamento e da espécie. O alagamento do solo reduziu o crescimento de plântulas de G. americana, diminuindo a massa seca foliar e do sistema radicular, a relação raiz/parte aérea e a altura da planta, não apresentando qualquer alteração morfológica. Por outro lado, o crescimento de plântulas de C. myrianthum foi estimulado sob condição de inundação, apresentando um aumento na massa seca, na relação raiz/parte aérea, na altura, no diâmetro do caule e algumas alterações morfológicas do caule, como a hipertrofia do colo da planta. Estes resultados vêm confirmar observações de campo indicando que ambas as espécies poderiam ser indicadas para programas de revegetação de áreas neotropicais sujeitas a inundações.

The objective of this study was to investigate (1) whether the reproductive phenology of Psychotria tenuinervis Muell. Arg. is influenced by climatic conditions (precipitation and temperature); (2) whether there are differences in the reproductive phenology of P. tenuinervis between fragments (fragment scale); and (3) whether there are differences in the reproductive phenology of P. tenuinervis among anthropogenic edges, natural edges, and in the forest interior within a fragment (habitat scale). The patterns of flowering and fruiting found in 2002 and 2003 were similar between forest fragments, and proximate factors were not very important in determining the reproductive phenology of P. tenuinervis. There was phenological similarity among the three habitats on a habitat scale, probably because of the extensive heterogeneity within each habitat, with the percentage of flowering and fruiting individuals and the intensity and duration of these phenophases varying among the sample plots. This high variability within habitats indicated that factors other than the distance from the edges (i.e., gaps, matrix composition, and edge age) probably had a greater influence on the reproductive phenology of P. tenuinervis. These results also indicate that heterogeneity within fragmented habitats needs to be considered in conservation and management programs for fragmented landscapes.

The aim of this work was to investigate whether (i) the organisms within different fragments