Crescimento e desenvolvimento inicial do ipê amarelo (handroanthus serratifolius (vahl) s.o. grose): morfologia e quantificação de 20-hidroxiecdisona.

Abstract

The ecdysteroid (ECD) hormone 20-hydroxyecdysone (20E) is found in all arthropods (Zooecdysteroids, ZES) and some plants (Phytoecdysteroids, PEs). The ECDs may have agrochemical, biotechnology, medical and pharmacological applicability. In order to analyze the presence and levels of PE 20E during growth and early development of yellow ipe (Handroanthus serratifolius (Vahl) SO Grose), morphological features were first analyzed. The morphological characterization revealed: i) the identification of the seminiferous nucleus, root, primary root, secondary root, epicotyl, integument, cotyledon, first eophyll, leaf, stem and roots and ii) the individualization of the different plant parts. The 20E spatial and temporal analysis was performed by high performance liquid chromatography (HPLC) during 186 days after seed imbibition. The HPLC analysis of the methanol extract of seeds, not imbibed; imbibed seeds; imbibed seeds showing radicle, cotyledons and primary root; epicotyl; eophylls; leaves; stems; and roots showed the presence of a molecule that has the same retention time of 20E, except eophylls. Analysis of dry mass in the different organs and the percentage of this molecule allowed determination of its accumulation in seeds during germination of the embryo leaves epicotyl, stems and roots. In cotyledons, the amount of this molecule decreases reaching undetectable levels. Collectively, the results demonstrate that a molecule that has the same 20 retention time was detected in yellow ipe during initial growth and development, and it is accumulated in all organs analyzed except for eophylls. Mass spectrometry analysis will determine the precise identity of this molecule.