En el marco de un ingreso universitario diseñado con inclusión de tecnología en modalidad b-learning se han puesto de manifiesto la presencia de ciertas brechas de acceso, uso y apropiación por parte de jóvenes aspirantes. En este trabajo se presentan los resultados del análisis de encuestas administradas a los alumnos ingresantes a la Facultad de Ciencias Naturales e Instituto Miguel Lillo, en la Universidad Nacional de Tucumán, Argentina, en el periodo 2017, comparando algunas variables con las cohortes 2015 y 2016. Los resultados han permitido identificar factores institucionales y contextuales referidos a la accesibilidad digital de los ingresantes, que deben ser tenidos en cuenta en el diseño de las próximas ediciones del curso para poder disminuir las brechas mencionadas.

A procedure for in vitro plant regeneration of Alnus acuminata from epicotyls with cotyledonary buds was developed using different media formulations with different growth regulators and carbon sources. The development of multiple buds on explants at the initiation step was obtained with MS at 1/2 strength with either 1 or 2 lM of BAP but not without it. Multiplication gave up to 15 elongating shoots by explant, the best medium being MS supplemented with vitamins from B5 medium, 1 lM of BAP and 87 mM sucrose. Rooting of about 88% occurred in the medium MS with 83 mM sucrose and 1 lM IBA. Alnus acuminata did not developed well on WPM. Roots of in vitro propagated plants were nodulated by Alnus-infective Frankia. The root nodules show a typical alder root nodule anatomy and differentiation pattern and effectively fixed nitrogen. Rhamnaceae-infective Frankia did not nodulate in vitro cultivated Alnus acuminata suggesting that symbiotic recognition was not altered by in vitro regeneration of the plant.

Zuccagnia punctata Cav. (Fabaceae) is a medicinal aromatic shrub, a monotypic species with a wide distribution in Argentina. Two morphotypes were found in Valles Calchaquíes, one with yellow fruits (YF) and other with red-brown fruits (RBF). The color of fruits varies between individuals within a population, with some plants producing red-brown fruits and other yellow fruits. The cytogenetic differentiation was determined using root tips. Leaves and fruits were used to analyze chemical composition by HPLC-DAD and HPLC/MS/MS. The number of chromosome (2n = 24) was reported for the first time for the genus. The yellow fruits and red-brown fruits morphotypes showed different karyotypes. The compounds common to both morphotypes were identified in leaves and fruits as chalcones, compounds with biological activity and biomarkers used for quality control of Z. punctata products. Two chemotypes related to the color of the fruits, were detected. An anthocyanin, cyanidin 3-glucoside was found in red-brown fruits (4.75 mg.g-1 fruits) but not in yellow fruits. These is the first report on yellow fruits morphotype of Z. punctata and on presence of anthocyanins in Z. punctata red-brown fruits morphotype. This work contributes to the knowledge of Z. punctata, a native plant from Argentina with high economic potential to promote the regional economy.