Effect of morphological heterogeneity of somatic embryos of Melia azedarach on conversion into plants

Embryogenic cultures were initiated from immature Melia azedarach (Meliaceae) zigotic embryos. Explants were induced on Murashige and Skoog (1962) medium with 4.54 microM thidiazuron or 0.45 microM dichlorophenoxyacetic acid. After 6 weeks of culture on induction medium, somatic embryos were categorized in four morphological classes based on the presence of single or fused embryos and if they remained united or not to the original explant; that were evaluated histologically. The somatic embryos of every category were transferred, in groups or individually, on a 1/4 MS medium. Bipolar embryos, the more typically normal ones, had well defined shoot and root apical meristems and produced single plants; subcultured individually their conversion was 28%, and subcultured in groups the conversion declined to 6.8%. Fused embryos subcultured in groups had only a 2.1% conversion and produced plants with fused stems. None conversion rate in the others classes was associated to poorly developed shoot and root meristematic areas or with their absence. The converted plants were acclimatized and transferred, in a mist, to soil, with an independent of the class 95% survival rate.

Posibles factores incidentes en el tratamiento de la sensibilidad al ruido / Possible incident factors in the treatment of sensibility to noise

Sobre la base de la teoría de Eysenck, se plantea la hipótesis de que los sujetos distímicos serán accesibles al tratamiento de la sensibilidade al ruido y por medio de técnicas de relajación, en tanto que los sujetos histéricos no lo serán. A un grupo de sujetos voluntarios, sensibles al ruido, se le aplica el tratamiento en cuatro sesiones. La comparación de las curvas individuales de sensibilidad al ruido, pre y pos-tratamiento y el análisis del cruce de variables realizado, evidencia que, contrariamente a la hipóteses planteada, el factor de mayor incidencia en los resultados del tratamiento, es el grado de sensibilidad al ruido que presentan los sujetos experimentales