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Abstract Piper tuberculatum (Piperaceae) is a species that accumulates especially amides as secondary metabolites and several biological activities was previously reported. In this article, we report a proteomic study of P. tuberculatum. Bidimensional electrophoresis (2D SDS-PAGE) and mass spectrometry (ESI-Q-TOF) were used in this study. Over a hundred spots and various peptides were identified in this species and the putative functions of these peptides related to defense mechanism as biotic and abiotic stress were assigned. The information presented extend the range of molecular information of P. tuberculatum.

Resumo Piper tuberculatum (Piperaceae) é uma espécie que acumula especialmente amidas como metabólitos secundários e diversas atividades biológicas dessa espécie foram relatadas anteriormente. No presente artigo, relatamos um estudo proteômico dessa espécie. Eletroforese bidimensional (2D SDS-PAGE) e espectrometria de massas (ESI-Q-TOF) foram utilizadas nesse estudos. Mais de cem spots e vários peptídeos foram identificados nesta espécie e as funções putativas desses peptídeos relacionadas a mecanismo de defesa como estresse biótico e abiótico foram atribuídos. As informações apresentadas ampliam a gama de informações moleculares dessa espécie.

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Piper tuberculatum (Piperaceae) is a species that accumulates especially amides as secondary metabolites and several biological activities was previously reported. In this article, we report a proteomic study of P. tuberculatum. Bidimensional electrophoresis (2D SDS-PAGE) and mass spectrometry (ESI-Q-TOF) were used in this study. Over a hundred spots and various peptides were identified in this species and the putative functions of these peptides related to defense mechanism as biotic and abiotic stress were assigned. The information presented extend the range of molecular information of P. tuberculatum.

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Studies on the anatomy of Piper leaves demonstrate the presence of a subepidermal tissue distinct from the adjacent epidermis, which cells show thin walls and hyaline contents. Some authors consider such cells a hypodermal tissue, while others refer to them as components of a multiple epidermis. In this study, the nature of this subepidermal tissue was investigated through the analysis of leaf ontogeny in three Piper species. The analysis showed that the referred tissue originates from the ground meristem and, thus, should be considered a hypodermis. The studied species suggests that the role of the hypodermis would be to protect the photosynthetic apparatus from excess light, regulating the intensity of light reaching the chlorophyll parenchyma.

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Studies on the anatomy of Piper leaves demonstrate the presence of a subepidermal tissue distinct from the adjacent epidermis, which cells show thin walls and hyaline contents. Some authors consider such cells a hypodermal tissue, while others refer to them as components of a multiple epidermis. In this study, the nature of this subepidermal tissue was investigated through the analysis of leaf ontogeny in three Piper species. The analysis showed that the referred tissue originates from the ground meristem and, thus, should be considered a hypodermis. The studied species suggests that the role of the hypodermis would be to protect the photosynthetic apparatus from excess light, regulating the intensity of light reaching the chlorophyll parenchyma.

Os estudos de anatomia foliar de espécies de Piper revelam a presença de um tecido subepidérmico distinto da epiderme e cujas células apresentam paredes finas e conteúdo hialino. Estas células são referenciadas por alguns autores como um tecido hipodérmico e por outros, como sendo constituintes de uma epiderme múltipla. Nesse estudo verificou-se a natureza deste tecido subepidérmico a partir da análise da ontogênese foliar de três espécies de Piper. A análise revelou que o referido tecido tem origem do meristema fundamental e, portanto, deve ser denominado de hipoderme. Para as espécies avaliadas, sugere-se que a hipoderme teria função de, proteger o aparato fotossintético do excesso de luminosidade, regulando a intensidade luminosa que atinge o parênquima clorofiliano.

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Studies on the anatomy of Piper leaves demonstrate the presence of a subepidermal tissue distinct from the adjacent epidermis, which cells show thin walls and hyaline contents. Some authors consider such cells a hypodermal tissue, while others refer to them as components of a multiple epidermis. In this study, the nature of this subepidermal tissue was investigated through the analysis of leaf ontogeny in three Piper species. The analysis showed that the referred tissue originates from the ground meristem and, thus, should be considered a hypodermis. The studied species suggests that the role of the hypodermis would be to protect the photosynthetic apparatus from excess light, regulating the intensity of light reaching the chlorophyll parenchyma.(AU)

Os estudos de anatomia foliar de espécies de Piper revelam a presença de um tecido subepidérmico distinto da epiderme e cujas células apresentam paredes finas e conteúdo hialino. Estas células são referenciadas por alguns autores como um tecido hipodérmico e por outros, como sendo constituintes de uma epiderme múltipla. Nesse estudo verificou-se a natureza deste tecido subepidérmico a partir da análise da ontogênese foliar de três espécies de Piper. A análise revelou que o referido tecido tem origem do meristema fundamental e, portanto, deve ser denominado de hipoderme. Para as espécies avaliadas, sugere-se que a hipoderme teria função de, proteger o aparato fotossintético do excesso de luminosidade, regulando a intensidade luminosa que atinge o parênquima clorofiliano.(AU)

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PREMISE OF THE STUDY: Dichogamy is a common characteristic among angiosperms, including Piper species. In this genus, the tiny flowers are morphologically similar and have an asynchronous stamen development. However, there is no information on the duration of stigma receptivity and whether it overlaps with pollen release. To better understand mechanisms of floral function in Piper vicosanum, we provide a detailed characterization of the timing of pollen release from the four stamens and the period of stigma receptivity and exposure mode of the receptive areas. METHODS: We investigated plants of a natural population in a semideciduous seasonal forest (Viçosa, Minas Gerais State, southeastern Brazil), based on chemical tests, light microscopy, and scanning electron microscopy analyses. KEY RESULTS: Incomplete protogyny-a mechanism that favors outcrossing-was recorded. The period of stigma receptivity was long (14 d), and the sequential exposure and senescence of stigmatic papillae occurred gradually and in a basipetal direction. Pollen release began 2-6 d after the beginning of the pistillate phase, with an average pollen viability of 87.7%, during the bisexual flower phase. Pollen was released for up to 6 d and occurred in one stamen at a time. The fruit set observed in tests of self-pollination indicated self-compatibility. CONCLUSIONS: The gradual and sequential exposure of stigmatic papillae in P. vicosanum flowers is described here as the mechanism for the long duration of receptivity. Anther development and pollen release were also sequential. These findings are yet unreported reproductive characteristics of the genus and offer new perspectives for future studies on the floral biology of other Piper species.

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Introducción: los estudios farmacognósticos son de vital importancia en la investigación de plantas medicinales, así como en la producción de medicamentos herbarios y fitofármacos. La especie Piper aduncum L (Piperaceae), posee un gran aval de uso tradicional en Cuba y otras regiones del mundo. Objetivo: estudiar desde el punto de vista farmacognóstico la droga de Piper aduncum en cuanto a botánica, geografía y etimología. Métodos: se realizó el estudio botánico, de distribución geográfica y etimología de esta droga, mediante el empleo de literatura especializada y la determinación de caracteres macromorfológicos de hojas de esta planta colectada en la provincia Ciego de Ávila, Cuba. Resultados: existen 2 categorías infraespecíficas bien localizadas geográficamente de la planta que en Cuba se llama por lo común platanillo de Cuba, guayuyo o canilla de muerto, una de las cuales -Piper aduncum subespecie ossanum (C.DC.) Saralegui-, endémica, es la que se investiga. Las características macromorfológicas de la droga coinciden con las descritas en la literatura. Se hallaron aspectos etimológicos y de distribución geográfica de interés relacionados con esta planta. Conclusiones: en las investigaciones farmacognósticas los estudios botánicos, geográficos y etimológicos pueden ser de gran significación, como en el caso de esta planta. Para cualquier investigación con esta especie resulta imprescindible abordar su tratamiento taxonómico en el país, porque incluye 2 categorías infraespecíficas en las cuales la ubicación geográfica es fundamental

Introduction: pharmacognostic studies are essential on medicinal plant research, as well as in herbal medicine and phytomedicine production. Piper aduncum L. (Piperaceae) specie known as "platanillo de Cuba", has wide recognition due to its traditional use in Cuba and other regions. Objective: to research the drug derived from Piper aduncum (platanillo de Cuba) from the pharmacognostic viewpoint in terms of pharmacobotany, pharmacogeography and pharmacoetymology. Methods: the pharmacobotanical, geographical distribution and etymological study of this drug was conducted by using specialized literature and determination of macromorphologic characteristics of leaves collected in Ciego de Ávila province, Cuba. Results: there are two geographically located infraspecific taxa of the plant commonly called "platanillo de Cuba", "guayuyo" o "canilla de muerto" in Cuba. One of them -Piper aduncum subspecie ossanum (C.DC.) Saralegui- is endemic and the topic of this research. Macromorphologic characteristics of the drug are comparable to those described in literature. Geographical distribution and etymologic aspects of interest were found. Conclusions: in the pharmacognostic research, pharmacobotanical, pharmacogeographical and pharmacoetymological studies could be very signicant, as in the case of this plant. For any further research on this species, it is fundamental to approach its taxonomic treatment in the country, since it includes two infraspecific taxa in which geographical location is essential.

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Understanding the effects of disturbance and secondary succession on spatio-temporal patterns in the abundance of species is stymied by a lack of long-term demographic data, especially in response to infrequent and high intensity disturbances, such as hurricanes. Moreover, resistance and resilience to hurricane-induced disturbance may be mediated by legacies of previous land use, although such interactive effects are poorly understood, especially in tropical environments. We address these central issues in disturbance ecology by analyzing an extensive dataset, spanning the impacts of Hurricanes Hugo and Georges, on the abundance of a Neotropical walking stick, Lamponius portoricensis, in tabonuco rainforest of Puerto Rico during the wet and dry seasons from 1991 to 2007. By synthesizing data from two proximate sites in tabonuco forest, we show that resistance to Hurricane Hugo (97% reduction in abundance) was much less than resistance to Hurricane Georges (21% reduction in abundance). Based on a powerful statistical approach (generalized linear mixed-effects models with Poisson error terms), we documented that the temporal trajectories of abundance during secondary succession (i.e., patterns of resilience) differed between hurricanes and among historical land use categories, but that the effects of hurricanes and land use histories were independent of each other. These complex results likely arise because of differences in the intensities of the two hurricanes with respect to microclimatic effects (temperature and moisture) in the forest understory, as well as to time-lags in the response of L. portoricensis to changes in the abundance and distribution of preferred food plants (Piper) in post-hurricane environments.

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The stems of some myrmecophytes in Piper are used as domatia by resident ant colonies. Hollow, ant-occupied stems were previously known only in four species of southern Central American Piper, all members of Section Macrostachys. Here we present two additional, unrelated, hollow-stemmed myrmecophytes from Ecuador: P. immutatum and P. pterocladum (members of sections Radula and Peltobryon, respectively). Although similar superficially, stem cavities of the Ecuadorian Piper species differ morphologically and developmentally from those of Central American taxa. The stem cavities of P. immutatum, and possibly P. pterocladum, are formed during stem development, and begin forming only a few millimeters behind the apical meristem. This mode of cavity formation differs markedly from myrmecophytes in section Macrostachys, where the stems remain solid unless excavated by the specialized ant partner Pheidole bicornis. The stems of P. immutatum and P. pterocladum do not produce wound-response tissue around the cavity, unlike the stems in section Macrostachys. The entrance holes in stems of P. immutatum are formed through apoptotic processes and are located at each node below the petiole, whereas those in section Macrostachys are excavated by the ants in the leaf axil. This study documents convergent evolution of ant-plant associations in Piper, and emphasizes the need for careful comparison of apparently homologous, ant-associated structures in specialized myrmecophytes.

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Variation in plant species performance in response to water availability offers a potential axis for temporal and spatial habitat partitioning and may therefore affect community composition in tropical forests. We hypothesized that short dry spells during the wet season are a significant source of mortality for the newly emerging seedlings of pioneer species that recruit in treefall gaps in tropical forests. An analysis of a 49-year rainfall record for three forests across a rainfall gradient in central Panama confirmed that dry spells of > or = 10 days during the wet season occur on average once a year in a deciduous forest, and once every other year in a semi-deciduous moist and an evergreen wet forest. The effect of wet season dry spells on the recruitment of pioneers was investigated by comparing seedling survival in rain-protected dry plots and irrigated control plots in four large artificially created treefall gaps in a semi-deciduous tropical forest. In rain-protected plots surface soil layers dried rapidly, leading to a strong gradient in water potential within the upper 10 cm of soil. Seedling survival for six pioneer species was significantly lower in rain-protected than in irrigated control plots after only 4 days. The strength of the irrigation effect differed among species, and first became apparent 3-10 days after treatments started. Root allocation patterns were significantly, or marginally significantly, different between species and between two groups of larger and smaller seeded species. However, they were not correlated with seedling drought sensitivity, suggesting allocation is not a key trait for drought sensitivity in pioneer seedlings. Our data provide strong evidence that short dry spells in the wet season differentially affect seedling survivorship of pioneer species, and may therefore have important implications to seedling demography and community dynamics.

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