In vitro cloning advances of adult trees of rauli (Nathofagus alpina Poepp. et Endl.) Oerst) trees for commercial propagation

Rauli, Nothofagus alpina (= N. nervosa) is a species native to Chile with commercial potential. This study describes the procedure for in vitro establishment of adult phenotypes of rauli from two sources, field and graft, cultivated in vitro for periods of several years to produce plants of adequate size and form for commercial scale use. We discuss the results obtained in the rooting phase. The species kept in in vitro culture with constant concentration of BAP (0.125 mg L-1) propagates with no decline in rooting potential after several years of successive subcultures in the laboratory. To evaluate rhizogenic potential over time, two treatments were tested: shoot rooting one year after establishment in vitro and four years of successive subcultures. No significant differences in percentages of rooting were found for treatments or sources. The possibility of maintaining rhizogenic potential of a species cultivated in vitro for prolonged periods is an advantage in implementing a program of large-scale production of clones using micropropagation techniques.