Caracterização genética e propagação in vitro de Pau-Rosa (Aniba Rosaeodora Ducke)

Abstract

Amazonian rosewood (Aniba rosaeodora Ducke, Lauraceae) has ecologic and economic importance in the region. As a consequence of its economic importance, rosewood populations have been decimated in the forest. Species of nine genera of the Lauraceae family have characterized karyotypes with n=x=12 chromosomes in the gametophytic phase. The Aniba genus is one of the least studied members of the Lauraceae family and the genomes of these species are still undescribed. The karyotype was found to contain 12 pairs (2n=24) of relatively small submetacentric chromosomes, with lengths from 1.34 to 2.25 μm. The presence of the nucleolar organizer region in the short arm of chromosome 7 was identified. The genome size was determined by flow cytometry with a 2C value = 2.32 pg of DNA (approximately 2.24x109 base pairs). In this study, was developed also a system of micropropagation has been for the conservation of the genetic diversity of the rosewood. In vitro propagation of rosewood was achieved using seedling shoot tip explants on Murashige and Skoog (MS) medium supplemented with combination 6 Benzilaminopurine (BAP) and indole- 3- acetic acid (AIA). The greatest proliferation rate (4.50 shoots/explant) was achieved in 15 μM BAP +10 μM AIA. Rooting in vitro was also greatest (up to >60%) with 0 μM BAP + 25 μM AIA. These results suggest that the combination auxin and cytocinina is an alternative important of success in vitro propagation of A. rosaeodora although require individual optimizations of treatments to maximise shoot and root formation.