Regeneração in vitro de segmentos nodais de Libidibia ferrea (Mart. ex Tul.) L.P. Queiroz sob diferentes concentrações e combinações de reguladores de crescimento e fontes luminosas

Abstract

Libidibia ferrea (Mart. ex Tul.) L.P. Queiroz, popularly known as pau-ferro or jucá, is a plant species belonging to the family Fabaceae-Caesalpinoidae that has great medicinal value due to the potential of its active ingredient "Pau-ferrol A", which can be used as an important tool in the treatment of leukemia Human HL60. However, this species has been undergoing an intense process of extractivism practiced indiscriminately in their natural populations, in addition to of this, causing the genetic erosion and destruction of its habitat in the Amazon, where the irregular seed production combined with high integumentary dormancy has limited the production of seedlings aiming at the recomposition of natural populations and plantations ex situ. The study aimed to evaluate the physiological responses of seedlings of pau-ferro, developed in vitro, under different concentrations and combinations of growth regulators and light sources in the in vitro propagation of ironwood through an efficient alternative to promote the reproduction of genotypes through in vitro conditions of this species. The study was conducted in the National Research Institute's Forestry and Digital Technologies Laboratory da Amazônia (LASTED/INPA) Manaus, Amazonas, where nodal segments, originating from of the in vitro establishment of L. ferrea seeds following Silva's methodology et al., (2018), were inoculated in MS culture medium (SIGMA, M5519-50L, USA) plus different combinations of auxins and cytokinins in concentrations of 0.03 + 0.06 (mgL-1 ) and 0.05 + 0.1 (mgL-1 ), respectively. The auxins used were naphthaleneacetic acid (ANA), indole-3-acetic acid (IAA) and 3-indole-butyric acid (IBA), and the cytokinins were 6-benzylaminopurine (BAP), kinetin (KIN) and thidiazuron (TDZ). The results obtained suggest that the interaction of ANA and BAP (0.05 and 0.1 mg L -1 ), stimulated the highest rate of regeneration under blue-red LED, while the interaction of AIA and BAP (0.05 and 0.1 mg L-1 ) stimulated a higher multiplication rate under White LED, none of the treatments resulted in root growth. Key Words: Cytokinins, auxins, nodal segments, light sources