Tissue culturing is widely used for the clonal propagation of several plant species. However, high mortality rates may occur during the acclimatization phase due to the sudden, dramatic changes in light levels. This study evaluated the effect of light level during the acclimatization of Neoregelia concentrica (Vellozo) LB Smith using chlorophyll a fluorescence and growth analysis. N. concentrica plants were multiplied and rooted in vitro on Murashige and Skoog medium and then transferred to plastic trays with individual cells containing vermiculite. The treatments consisted of the ex vitro cultivation of plants under light levels of 30, 50, 70, and full sunlight (100% light) for 28 d. Chlorophyll a fluorescence measurements were taken at 0 (in vitro), 7, 14, 21, and 28 d of acclimatization, and growth trait analyses were made at 28 d. The high irradiance under full sunlight (100% light) induced photoinhibition and reduced the growth rate. Plants grown under partial light (30, 50, and 70%) were less inhibited. A 50% reduction in light level during N. concentrica acclimatization produced rapid plant recovery and higher growth rates than full sunlight.
The tissue culture can contribute to the propagation of several economic species, such as the bromeliads. This research aimed at evaluating the auxins type and concentration in the in vitro and ex vitro rhizogenesis of Neoregelia concentrica bromeliad. N. concentrica shoots were induced in a growth medium with 15.0 µM of 6-benzylaminopurine, for 80 days, followed by sub-cultivation in phytoregulator-free medium, for 45 days. In the in vitro rhizogenesis, the shoots grew in a medium supplemented with indole-3-butyric acid (IBA) or naphthalene-acetic acid (NAA), at the concentrations of 0.0 µM, 1.0 µM, 2.0 µM, 3.0 µM and 4.0 µM. In the ex vitro rhizogenesis, the bases of shoots were immersed, for 60 minutes, in IBA or NAA solutions, at the concentrations of 0.0 µM, 5.0 µM, 10.0 µM and 15.0 µM. After immersion, the shoots were planted in plastic trays with vermiculite. At the end of each rhizogenesis method, the phytotechnical parameters analysis was carried out. For the in vitro rhizogenesis, a higher number of roots were observed when the shoots were cultivated in concentrations higher than 1.0 µM of NAA, when compared to the IBA. However, the rooting rate differed only at 30 days after the in vitro growth, with a higher root induction in the shoots grown with NAA. At 60 days, the rooting rate was higher than 90% and statistically similar in all treatments. In the ex vitro rhizogenesis, a better formation of the rooting system was observed when 5.0 µM of IBA was applied, with higher rooting averages and number of roots.
O perfil da pandemia de Aids vem sendo marcado pela feminização,envelhecimento, pauperização, heterossexualização e interiorização. A microrregião São Mateus é limítrofe aos estados da Bahia e Minas Gerais, caracterizada por carência social e grande afluxo de pessoas em busca de atividades econômicas e acesso a serviços de saúde. Objetivou-se descrever a tendência da Aids segundo categoria exposta, na Microrregião São Mateus, no Espírito Santo (ES) e no Brasil, no período de 1999 a 2008. Os dados foram coletados no Sistema de Informação de Agravos e Notificações (SINAM); realizou-se análise de tendência no programa GENES. No geral, a primeira, segunda e quarta maior média de casos ocorreu na exposição heterossexual, ignorada e usuários de drogas injetáveis, respectivamente. Por área avaliada, a transmissão homossexual foi a terceira maior no ES e Brasil e quinta maior na Microrregião; transmissão vertical (TV) terceira maior na Microrregião e sexta maior no Brasil e ES. As tendências foram crescentes em todas as categorias na Microrregião; somente nas ignoradas, usuários de drogas injetáveis e TV no ES; e ignorada e TV no Brasil. A Microrregião apresentou perfil semelhante ao estadual e nacional, mas com particularidades que apontam para a presença de subepidemias regionais.
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