Influence of the in vitro environment on the germination of somatic embryos of <i>Coffea arabica</i> L. cv. 'Caturra rojo' and <i>Clematis tangutica</i> K.

Abstract

The in vitro environment is a factor that in recent years has begun to investigate, because gases such as oxygen, carbon dioxide and ethylene play an important role in the morphogenesis of somatic embryos and their development in plants. The objective of this work was to determine the effect of the CO2 on the germination of coffee somatic embryos (Coffea arabica L. cv. 'Caturra rojo') and clematis (Clematis tangutica K.). Three gas mixtures composed of CO2 concentrations (2.5, 5.0 and 10.0%) combined with 21% O2 and two controls (passive exchange and forced ventilation) were used. A positive effect of CO2 on the germination of somatic embryos in the torpedo stage in coffee and clematis was obtained, because in the treatments with passive exchange, where there was CO2 accumulation, germination of the somatic embryos was superior to the treatments with Forced ventilation. With 2.5% and 5.0% CO2, the germination process is stimulated while with 10.0% CO2 there is an inhibition of germination with the appearance of malformations and hyperhydricity. Keywords: gaseous atmosphere, carbon dioxide, somatic embryogenesis, secondary embryogenesis, hyperhydricity