Reproductive Phenology, Floral Morphology And Incompatibility System In Distylous Species Of Rubiaceae In A Forest Fragment In Southeastern Brazil [fenologia Da Floração, Morfologia Floral E Sistema De Incompatibilidade Em Espécies Distílicas De Rubiaceae Em Fragmento Florestal Do Sudeste Brasileiro]

This work was carried out at the Estação de Pesquisa, Treinamento e Educação Ambiental Mata do Paraíso, Viçosa, Minas Gerais State, a forest fragment in the Atlantic Forest. Its main objective was to analyze the flowering phenology, floral morphology, and incompatibility system of the distylous species of Rubiaceae: Palicourea longepedunculata Gardner, P. marcgravii A. St.-Hil., Psychotria conjugens Müll. Arg., P. hastisepala Müll. Arg., P. hygrophiloides Benth., P. nuda (Cham. & Schltdl.) Wawra, P. sessilis Vell. and Rudgea lanceolata Nutt. It also aimed to verify whether the floral morphs were in balanced equilibrium. The flowering in the species of Psychotria conjugens, P. hastisepala, P. hygrophiloides and P. sessilis were sequential, occurring during the rainy season (September through March). Significant differences were observed in the lengths of the stamens and styles between the thrum and pin flowers, except for P. hygrophiloides, in which only thrum flowers could be observed. Furthermore, dimorphism was observed in the length of stigmatic lobules, corollas, corolla lobules and anthers. Flowers opened in the morning lasting about 24 h, except for P. nuda flowers, that lasted 48 h. In most of the species the floral morph ratio was 1:1, except P. marcgravii, P. conjugens and P. hygrophiloides. 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Presença do arilo na produção de mudas de Maytenus ilicifolia Presence of arils over Maytenus ilicifolia seedlings production

A propagação da espinheira-santa (Maytenus ilicifolia) é feita por sementes, sendo indicada a retirada do arilo para a semeadura, prática que demanda muito tempo e mão-de-obra. O experimento foi instalado com o objetivo de avaliar a influência do arilo na produção de mudas de espinheira-santa. Foram utilizados dois acessos do Banco Ativo de Germoplasma de M. ilicifolia da Embrapa Clima Temperado, 30 e 91. Os tratamentos utilizados foram: T1 - sementes com arilo retirado logo após a abertura das cápsulas (armazenadas em câmara fria sem arilo); T2 - sementes com arilo retirado no dia da semeadura (armazenadas em câmara fria com arilo) e T3 - sementes sem a retirada do arilo. Foram avaliados: dias da semeadura à emergência (DSE); porcentagem de emergência em canteiros (%EC); comprimento da parte aérea (CPA); diâmetro da base do caule (DBC) e número de folhas/planta (NF). A presença do arilo nas sementes de M. ilicifolia não influenciou os caracteres DSE, %G, DBC e NF, podendo influenciar apenas no caráter comprimento da parte aérea, dependendo da constituição genética da população, não sendo necessária a retirada do arilo para a semeadura.<br>Maytenus ilicifolia is propagated by seeds and it is indicated to remove arils before sowing, what requires much time and work. An experiment to evaluate the influence of arils over seedlings production was installed in Embrapa Clima Temperado, in Pelotas, RS. Two accesses (30 and 91) of M. ilicifolia Gene Bank were used. The treatments were: T1 - seeds with arils removed immediately after the capsules (fruits) being opened (stored in cold room without arils); T2 - seeds with arils removed in the sowing’s day (stored in cold room with arils); T3 - seeds with arils. The characters evaluated were: days of sowing to emergence (DSE); emergence percentage (%G); aerial part length (CPA); stem base diameter (DBC) and number of leaves/seedling (NF). The arils in the seeds of M. ilicifolia did not influence the characters DSE, %G, DBC e NF, but can influence the aerial part length (CPA), depending on the population genetic constitution. It is not necessary to remove the seeds arils to sowing of M. ilicifolia