GERMINAÇÃO E VIABILIDADE DE PROPAGAÇÃO POR SEGMENTOS FOLIARES DE PETÚNIA (Petúnia x hybrida)

Abstract

The petunia x hybrida is of ornamental interest of the solanacea family, whose origin is of South America (Brazil, Argentina and Uruguay). Petunias can be propagated sexually or asexually. The objective of this work was to analyze the °germination and development in vitro and ex vitro, as well as to obtain the bud formation in Petunia X hybrida leaf explants. The in vitro studies (germination and leaf cutting) were conducted at the Laboratory of Cell Biology and Culture of Tissues and the ex vitro (germination) in the environment of the Department of Biological Sciences of the Center of Agricultural Sciences of the Federal University of Paraíba - PB. The experiments were conducted in a completely randomized design - DIC, and in the germination experiments (in vitro and in vitro) seeds were used, where each seed constitutes an experimental plot. In the in vitro experiment the medium was reduced to half MS salts Murashige & Skoog (1962) and the ex vitro in substrate in the ratio of 1: 1 rice straw and vegetable soil. The number of seedlings emerged to evaluate the Germination Speed Index (IVG) and Percentage of Germination, at 14 days, plant height, root length, stem diameter, leaf length Stem and number of leaves. In the BAP (benzylaminopurine) leaf cutting experiment at different concentrations of 0.0; 0.5; 1.0 and 1.5 mg / L-1, being 4 treatments and 30 repetitions, totalizing 120 plots, containing three explants per plot. The percentage of total contamination of the explants (%), necrotic explants (%), viable explants (%) was evaluated at seven and fourteen days, and the counts of the shoots developed in each explant were counted at 14 days. The ex vitro sowing allowed a better germination and initial development of the Petunia x hybrida seedlings; Leaf explants of Petunia x hybrida form shoots/calli in the absence and with 1.5 mg.L-1 of benzylaminopurine; The presence of trichomes, characteristic of leaves of Petunia x hybrida contributes to the contamination of the explants, because it is in this structure where the microrganisms are housed.