ChileanJAR

A new procedure is described for in vitro multiplication using the temporary immersion system for plants (Eucalyptus grandis Hill ex Maiden) coming from elite trees. The optimum multiplication frequency was established at every 12 h with a duration of 3 min. The additional application of a stream of fresh air every 6 h for 3 min diminished the hyper-hydration of the plants during the process. The procedure involved two steps: shooting and elongation of buds. The best treatment for induction of axillary buds was obtained in the culture medium MS (Murashige and Skoog) with the nitrates reduced to half strength plus 0.5 benciladenin (BA) mg L^-1, with volumes of 55.5 mL per group of buds for three weeks. The elongation took place in the MS culture medium plus indol butiric acid (IBA) 1.0 g L^-1 for three weeks. The use of this protocol allows producing an average of 260 competent plants of E. grandis. Shoots taller than 2 cm were positively related with higher survival during the acclimatization phase.