Phoradendron is a New World genus of chlorophyllous hemiparasite plants with the distribution extending from the United States to Argentina, including the West Indies. The names given to the fruits within the Visceae are variable and include a viscous berry or pseudoberry bearing a single seed lacking the testa. Here, it was performed an anatomical study about the development of fruit and seed of three species of Phoradendron. During the fruit development the structure of the mesocarp undergoes intense activity of cell division, and it differentiates onto two new mesocarpic regions: the parenchyma and the viscid layer. In its maturity, the seed is ategmic, presenting the embryo entirely embedded within a chlorophyllous endosperm. The occurrence of chlorophyll in the endosperm may be associated to absence of integuments on the seed, which allows the light to reach the seminal tissues throughout the somewhat transparent pericarp. In addition, the Pomaceous fruit, "viscidio" type is proposed as an alternative classification for Phoradendron fruits. Key words: anatomy, chlorophyllous endosperm, fruit classification, semiparasite plant. ResumoPhoradendron é um gênero de plantas hemiparasitas clorofiladas do Novo Mundo, que tem distribuição desde os Estados Unidos até a Argentina, incluindo o leste da Índia. Os nomes dados aos frutos de representantes de Visceae são variáveis, incluindo baga viscosa ou pseudobaga, apresentando uma única semente sem testa. Nesse trabalho, foi realizado um estudo anatômico para investigar o desenvolvimento do fruto e da semente de três espécies de Phorodendron. Durante o desenvolvimento do fruto, a estrutura do mesocarpo sofre intensa atividade de divisão celular; diferenciando-se em duas novas regiões mesocárpicas: uma camada parenquimática e outra de viscina. Quando o fruto amadurece, a semente atégmica, apresenta embrião inteiramente embebido em um endosperma clorofiliano. A ocorrência de clorofila no endosperma pode estar associada à ausência de tegumentos seminais, permitindo que a luz alcance os tecidos da semente, através do um pericarpo relativamente transparente. Em adição, fruto Pomaceo do tipo viscidio é proposto como uma alternativa para a classificação de frutos para o gênero Phoradendron. Palavras-chave: anatomia, endosperma clorofiliano, classificação de frutos, planta hemiparasita.
Aiming to compare morphofunctional features related to dispersion and establishment of plants, this study evaluated seed biometry and biomass, as well as germination and emergence potential in eight plant species native to the Semideciduous Seasonal Forest. Biometric measurements and biomass of seeds were obtained with a caliper and a precision scale. Afterwards, they were subjected to a germination test in BOD chambers under constant temperature and 12 hours photoperiod, and sown in styrofoam trays containing organic substrate and sand, kept in full sunlight. Data from germination and emergence was subjected to cluster analysis, according to the functional morphotype of the seedling. Most species presented seeds with a rounded shape, uniform staining at the mature stage, varied coat consistency, two types of dispersal syndromes (anemochory and zoochory) and four morphofunctional patterns in developing seedlings (crypto-hypogeal-storers, crypto-epigeal-storers, phanero-epigeal-storers and phanero-epigeal-foliaceous). The species belonging to group I (Albizia niopoides, Cedrela fissilis, Pterogyne nitens and Randia ferox) have foliaceous photosynthetic cotyledons and group II (Cabralea canjerana, Eugenia pyriformis, Inga laurina and Poecilanthe parviflora) have a reserve cotyledon. Species of group I had higher means in the percentage and rate of germination, less variability and amplitude of days for seedlings emergence. On the other hand, species of group II showed higher mean values in seed biometry and biomass. Thus, seeds with foliaceous cotyledons have an optimized development because of luminosity, whereas seeds with reserve tend to have slower development, remaining at the seedling stage for a longer time.
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