Changes in Isoperoxidase Patterns during the in Vitro Rooting of Nothofagus Antarctica

Peroxidases play a major role in several physiological processes. Specifically, in vitro activity of this enzyme was used as a marker to identify different rooting phases of Nothofagus. The study of peroxidase profile patterns during rhizogenesis in this genus could give additional information about this topic, to justify the use of peroxidase isoforms as a more specific biochemical marker than total peroxidase activity. This work gives information on qualitative and quantitative changes in isoperoxidase expression (basic and acidic peroxidases) during in vitro rooting of N. antarctica microshoots through native PAGE. Time course analysis of isoperoxidase activity during rhizogenesis allowed positive correlation with specific morphogenic stages. Seventeen peroxidase bands were detected, 4 basic and 13 acidic. Four of the acidic peroxidases appeared during the induction stage of rooting. Variation in the number and relative activity of the isoperoxidases was found during different stages of adventitious rooting. The variation in the number and activity of isoperoxidases provides a good indicator of the processes involved in adventitious rooting of N. antarctica. Possible linkage of basic isoperoxidases with auxin metabolism and the role of certain isoperoxidases in specific rooting processes are also discussed.