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In vitro grown plants may have abnormal structural and physiological features. However, the type of the sealing material used in tissue culture may minimize such abnormalities. This study evaluates the influence of the type of sealing of test tubes on the anatomical and ultrastructural features of leaves of Aechemea bromeliifolia (Rudge) Baker (Bromeliaceae), an ornamental bromeliad native to Brazil, grown in vitro. Three types of sealing were used: rigid polypropylene cap (PC), polyvinyl chloride film (PVC), and PC coupled with a microporous membrane (PM). Seedlings germinated in a greenhouse were also studied for comparison. Plants grown in test tubes sealed with PM were more similar to those from the greenhouse, as far as the pattern of stomatal opening, the presence of starch grains, and the organization of the internal membrane system of the chloroplasts is concerned. Plants cultivated in test tubes sealed with PC had higher stomatal density and the chloroplasts had large areas without thylakoids in the stroma. Plants grown in test tubes sealed with PVC had few or no starch grains. These results suggest that microporous membrane used coupled with PC sealing provided natural ventilation, thus contributing to a better plant development. Resumo Plantas desenvolvidas in vitro podem apresentar características estruturais e fisiológicas pouco funcionais. Contudo, o tipo de vedação dos recipientes utilizados na cultura de tecidos pode minimizar tais características. Este estudo avaliou a influência do tipo de vedação dos tubos de ensaio sobre a anatomia e a ultraestrutura das folhas de Aechmea bromeliifolia (Rudge) Baker (Bromeliaceae), uma bromélia ornamental nativa do Brasil, desenvolvidas in vitro. Foram utilizados três tipos de vedação: tampa rígida de polipropileno (PC), filme de policloreto de vinila (PVC) e PC coberta com uma membrana microporosa (PM). Para efeitos de comparação, plantas provenientes de sementes germinadas em telado também foram estudadas. As plantas desenvolvidas em tubos vedados com PM se assemelharam mais às desenvolvidas em telado, quanto à abertura dos estômatos, a presença de grãos de amido e a organização do sistema interno de membranas dos cloroplastos. Nas plantas cultivadas em tubos vedados com PC, houve maior densidade estomática e os cloroplastos ficaram com grandes áreas sem tilacóides no estroma. Na condição PVC, pouco ou nenhum grão de amido foi encontrado. Esses resultados sugerem que a membrana microporosa, adicionada ao orifício da PC, proporcionou uma vedação com ventilação natural, contribuindo para o melhor desenvolvimento das plantas.

Natural ventilation micropropagation systems differ from conventional systems by allowing gas exchange between the internal and external media of the culture flask. The objective of this work was to compare the conventional system of in vitro propagation of Eugenia dysenterica (Mart.) DC. with a natural ventilation system. For shooting, explants were inoculated into test tubes with conventional lids and natural ventilation lids (NV), and WPM medium supplemented with four concentrations levels of 6-benzilaminopurine (BAP). The position of explants in each plant was considered by identifying buds as more proximate to the root, or to the apex, or in an intermediate position. Plant growth in the natural ventilation system was superior to that in the conventional system, with a 448.53% increase in leaf number, 85.64% increase in chlorophyll a levels and 74.90% increase in chlorophyll b levels. Plants with intermediate buds exhibited better results. Foliar anatomical analysis revealed abnormalities in leaves grown in the conventional system such as “giant” stomata, which remain always open. Our results indicate that the use of natural ventilation improves the water loss regulation capacity in micropropagated E. dysenterica plants and may favor plants survival and growth after transference to the natural environment.

The catalytic hydrogenation of the title allene-cyclopropane 1 is studied, using supported platinum and palladium catalysts, with the aid of ‘snapshot analysis’ graphs; other related results are reported.

Hydrogenation of the unsymmetrical title allene-cyclopropane 2 is studied graphically using ‘snapshot analysis’ and supported platinum, palladium and Raney nickel catalysts.