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RESUMENNothofagus glauca posee una situación privilegiada en asociaciones con especies problemáticas como Nothofagus alessandrii, Beilschmiedia berteroana y Nothofagus leonii, esto multiplica su valor ecológico y paisajístico, por las relaciones en su hábitat nativo. N. glauca se considera clave en determinados hábitats y su pérdida o continua disminución puede afectar directamente a otras especies. La conservación ex situ es una prioridad para el rescate de la especie, por tanto el cultivo de tejidos es, entre otros, uno de los mecanismos alternativos de propagación y conservación de las especies. El objetivo de este estudio fue evaluar el efecto independiente de dos auxinas, ácido naftalenacético (ANA) y ácido 3-indolbutírico (AIB), en el enraizamiento in vitro de microtallos de N. glauca provenientes de subcultivos sucesivos en medio MS como sustrato. Se establecieron seis tratamientos con: 1 mgl -1 , 3 mgl -1 y 5 mgl -1 de ANA y AIB, un control libre de hormonas y cuatro réplicas de cada uno. Se evaluó la supervivencia y enraizamiento de los microtallos, longitud de raíz (mm) y número de raíces por explanto. Se obtuvo supervivencia de hasta 100% con la adición de 3 mgl -1 de AIB al medio de cultivo. Se presentaron diferencias significativas entre el tratamiento control y microtallos sometidos a inmersión en hormonas. Se obtuvo 87,5% de enraizamiento adventicio con 1 mgl -1 de AIB y un 75,0% con 3 mgl -1 de ANA. Se concluye que la presencia de auxinas en el medio de cultivo es indispensable para la formación de raíces in vitro y establece la posibilidad de mantener el potencial rizogénico de la especie en condiciones ex vitro.PALABRAS CLAVE: Ácido 3-indolbutírico, ácido 1-naftalenacético, raíces adventicias, Nothofagus glauca. ABSTRACTNothofagus glauca forms essential associations with problematic species such as Nothofagus alessandrii, Beilschmiedia berteroana and Nothofagus leonii. By enhancing its native environment, N. glauca increases its ecological and scenic value. It is considered a keystone species in certain habitats, and its continued decline or loss may directly affect other species. Ex situ conservation is a priority for the recovery of the species; therefore, tissue culture is, among others, one of the alternative mechanisms for effective propagation and conservation of N. glauca. The aim of this study was to evaluate the independent effect of two auxins, 1-naphthalene acetic acid (NAA) and indole 3-butyric acid (IBA) in vitro rooting of microshoots of N. glauca from successive subcultures on MS medium. Six treatments were established containing 1 mgl -1 , 3 mgl -1 , and 5 mgl -1 of NAA and IBA. Experimental design included a hormone-free control and four replicates of each treatment. We evaluated the survival and rooting of the microshoots, the root length (mm), and the number of roots formed per explant. Survival of microshoots was recorded at 100% when 3 mgl -1 IBA was added to the culture medium. Furthermore, significant differences existed between the control treatment and the microshoots s...

From in vitro cultured adult material of Corylus avellana L. cv. Negretta, adventitious rooting of microshoots was evaluated. Rhizogenic induction mediated by two strains of wild-type Agrobacterium rhizogenes (A477 and A478) and indolbutyric acid (IBA) were compared under two light conditions (16:8 h photoperiod and complete darkness).The results indicate that in the 16:8 h photoperiod induction, the rooting rate with IBA (90%) was significantly higher than that obtained with the strain A477 of A. rhizogenes (67.7%), while with the strain A478 no statistically significant difference was obtained for the same variable (75%). On the other hand, under complete darkness, rooting mediated by IBA (90%) significantly surpassed the results obtained with both strains of A. rhizogenes (40 and 20%, for A478 and A477, respectively). In terms of the morphological variables of the resulting root system, induction mediated by IBA, with a 16:8 h photoperiod, generates a significantly higher number of roots (19 roots per microshoot) than that obtained with A. rhizogenes (mean 3.7 roots per microshoot), producing significant differences when comparing the results with the strain A478 (5 roots per microshoot) to those of the strain A477 (2.4 roots per microshoot). Induction under complete darkness does not have any effect on root number, independent of the rhizogenic inductor employed. Root length did not present significant differences among treatments, except in the presence of A. rhizogenes A477 and darkness.