Germinação in vitro de Adenium obesum (Forssk.) Roem. & Schult. (Apocynaceae). sob diferentes ambientes de cultivo.

Abstract

Many plant species are exploited for their ornamental purpose, amongst them, Adenium obesum, known popularly as Desert Flower or Desert Rose, is one that has been highlighted worldwide. The aim of this work was to determine the best cultivation environment for in vitro germination of A. obesum. The experiment was conducted at the Laboratório de Biologia Celular e Cultura de Tecidos Vegetais (LABCULTIVE/DCB/CCA/UFPB). The seeds were inoculated in a 1⁄2MS semi-solid culture medium and placed in the following cultivation environments: growth room, greenhouse without use of shading, greenhouse with the use of shading at 25%, 50%, 75% and 100%. The adopted design was randomized with six treatments with 60 repetitions each, with a total of 360 seeds. Was evaluated the percentage of germination, oxidation and seed contamination, Germination Speed Index (GSI/IVG), leaf and root length, length of the aerial part, number of leaves, neck diameter and weight of fresh mass. The in vitro germination starts in 2 to 4 days in a growth room and in a screened environment, regarding the cultivation environments, the highest IVG rate was obtained by the growth room, with 7,23/day, and followed by the screened environment without shading, with 5,39/day. The growth room and the screened environment without shading showed the highest percentages of germination, 94,6% and 71,7% respectively, the longest aerial part length, 3,49 cm and 2,88 cm, and the highest number of leaves, 3,65 and 3,05 respectively. The in vitro germination conditions favor the germination of A. obesum seeds, mainly in growth room and screened environment without shading.