Abstract

The Genipa americana L., a fruit-producing species found in several countries and commonly found in the Brazilian Northeast, is very important economically, both for its wood and as a source of food and dye. This study evaluate the effects of abscisic acid (ABA) and the concentrations of salt and sugar in MS medium on reducing Genipa americana L. growth for in vitro conservation, as well as the effects of benzylaminopurine (BAP) on the regrowth phase. Seedlings from accession CZA, after 90 days of in vitro cultivation, were transferred to Murashige and Skoog (MS) medium with 30 g L^-1 sucrose and various concentrations of ABA (0, 0.5, 1.0, 2.0 and 4.0 mg L^-1). In a second assay, various concentrations of MS medium salts and sucrose were tested. During the regrowth phase, nodal segments were placed in MS regeneration medium with 30 g L^-1 sucrose and BAP (0 or 1 mg L^-1). All the ABA concentrations affected the number of leaves, but significant effects on the length of aerial portion were not observed. The MS and ½ MS media with 30 g L^-1 sucrose slowed plant growth and are recommended for conservation protocols for slow growth. Adding 1 mg L^-1 BAP to the culture medium caused a greater morphogenic response, and the apical, medial and basal nodes retained morphogenic potential during regrowth.

Key words: Genipa americana L., germplasm, abscisic acid, sucrose.