Efeito do meio de cultura na calogênese in vitro a partir de folhas de erva-mate.

A organogênese é uma técnica pouco estudada na micropropagação de erva- mate. Este trabalho objetivou avaliar diferentes meios de cultura na calogênese in vitro e organogênese de Ilex paraguariensis St. Hil. Foram coletadas folhas em plantas em casa-de-vegetação. Segmentos foliares foram colocados em meios de cultura 1⁄4 MS, WPM ou JADS, contendo zeatina e 2,4-D. O meio MS foi mais eficiente na indução de calos. No meio WPM foi observada rizogênese. Nos meios testados não houve formação de brotações adventícias.Nota Científica

Properties of simulated sunspot umbral dots

Realistic 3D radiative MHD simulations reveal the magneto-convective processes underlying the formation of the photospheric fine structure of sunspots, including penumbral filaments and umbral dots. Here we provide results from a statistical analysis of simulated umbral dots and compare them with reports from high-resolution observations. A multi-level segmentation and tracking algorithm has been used to isolate the bright structures in synthetic bolometric and continuum brightness images. Areas, brightness, and lifetimes of the resulting set of umbral dots are found to be correlated: larger umbral dots tend to be brighter and live longer. The magnetic field strength and velocity structure of umbral dots on surfaces of constant optical depth in the continuum at 630 nm indicate that the strong field reduction and high velocities in the upper parts of the upflow plumes underlying umbral dots are largely hidden from spectro-polarimetric observations. The properties of the simulated umbral dots are generally consistent with the results of recent high-resolution observations. However, the observed population of small, short-lived umbral dots is not reproduced by the simulations, possibly owing to insufficient spatial resolution.Comment: Accepted for publication in A&

Estabelecimento e conservação in vitro de Ocotea spp.

EVINCI. Resumo