Optimizing Tectona grandis L.F. (teak) Tree Clonal Propagation via Regrowth and the Application of Plant Growth Regulators

Abstract

Tectona grandis L.F., known as teak, is a species of high commercial and ecological value for which the development of efficient clonal propagation strategies is being sought. The availability of clonally propagated materials from plus trees is scarce. The main objective of the research was to evaluate the root induction capacity of Tectona grandis L.F. plus tree sprouts using different hormone concentrations of indole-3-butyric acid (IBA) and 1-naphthaleneacetic acid (NAA) selected at 30 and 60 days. A completely randomized design (CRD) with seven treatments, four replicates, and three experimental units per replicate was used to determine statistical differences between treatments. The best results for rooting of teak shoots were observed in treatment T5 (500 mg kg-1 of IBA) with an average of three roots per plant, T1 (control), and T7 (1500 mg kg-1 of IBA) with an average of four leaves per plant. The highest survival rates were observed in T2 (500 mg kg-1 of NAA) and T7 (1500 mg kg-1 of IBA) with 58.33% and in T1 (control), T2 (500 mg kg-1 of NAA) 50% rooting was obtained after 60 days. Although no differences were observed between treatments, the numerical differences allowed to observe that the use of auxins promotes rooting and survival of the shoots of adult trees of T. grandis and opens the possibility of propagation and cloning strategies for this species. This study provides valuable knowledge on vegetative propagation, breeding and conservation of forest species, which is relevant for academia, public and private sectors.