In vitro induction of callogenesis and indirect organogenesis from explants of cotyledon, hypocotyl and leaf in Ugni molinae

Abstract

The objective of this study was to stimulate the production of calluses, to observe its typologies and organogenic response under different induction and differentiation mediums in explants from cotyledons, hypocotyls and leaves of Ugni molinae. Higher callus production was obtained with cotyledons in a Murashige and Skoog (MS) medium supplemented with 0.5 mg L^-1 of naphthaleneacetic acid (NAA), similar also in explants of hypocotyls with 1.0 and 5.0 mg L^-1 ofNAA, and in the control (62, 62, 74 and 64 %, respectively). Larger sizes of calluses were observed in cotyledons and smaller in leaves. Later, calluses were transferred to subcultures without growth regulators, where they were observed green, friable, compact and phenolic, obtaining the higher survival rates in calluses induced with 0.5 mg L^-1 of NAA for cotyledon and hypocotyl, and 1.0 mg L^-1 of NAA in leaf. Finally, the calluses derived from these treatments were cultivated in a differentiation medium with different concentrations of NAA plus 6-benzylaminopurine (BAP). The best organogenic responses were achieved with cotyledons in a medium without growth regulators and the rhizogenic in leaves with 0.1 mg L^-1 of NAA + 1.0 mg L^-1 of BAP. These results indicate that it is possible to stimulate different types of calluses and to obtain roots or shoots in U. molinae, which makes it possible to potentially use this technique for the conservation, micro-propagation and plants breeding of an endemic plant species.