Seedling regeneration of Eucalyptus grandis by in vitro direct organogenesis

Abstract

Eucalyptus grandis is one of the most cultivated forestry species in Brazil due to its fast growth and
good timber quality. With the objective of cloning E. grandis for seedling production, this study aimed to improve the micropropagation protocol by direct organogenesis. Micro cuttings from in vitro germinated seedlings were
inoculated in culture medium with different levels of growth regulators during the multiplication and rooting stages. During the multiplication stage, the addition of growth regulators did not promote significant increase in
bud number and height when compared to the control. Addition of ANA and IBA to the medium promoted higher rate of rooting and growth of roots, but an increase in concentration from 0,5 to 1mg/L of these growth regulators
reduced the root growth. The results of this study evidenced the possibility of micropropagation of Eucalyptus grandis by in vitro direct organogenesis.