Cultivo de embriões in vitro e emergência de plântulas de Musa submetidos à ação do ácido giberélico

Abstract

The wild banana trees have limitations on the seedling formation process. This study aimed to evaluate the effect of gibberellic acid on germination in vitro, emergence and initial growth of seedlings of wild banana (Musa). Seeds of mature fruits were obtained naturally from three Musa diploid (AA) genotypes from open pollinations with wild female parents carried out by the genetic improvement program of bananas and plantains of Embrapa Mandioca and Fruticultura. The seeds were soaked in solution containing 15 ppm gibberellic acid (GA3) and sterilized water for: 0, 24, 48 and 72 hours. For in vitro culture, the embryos were excised by means of a longitudinal section and MS culture medium was introduced. For in vivo cultivation, after soaking the seeds, sowing was carried out in trays containing coconut fiber as substrate. The analyzed variables were percentage, mean time and germination and emergency speed index; and initial development of seedlings. A completely randomized design with four treatments (GA3 imbibition time) was used, with each treatment containing six replicates with 10 seeds each. For germination, emergence and IVG, higher values were observed for genotype 2 in in vitro culture and genotype 3 in vivo culture. It was observed that soaking for 24 hours in genotype 2 and 48 hours for genotype 3 promoted greater efficiency in the initial development of seedlings cultured in vitro and in vivo, respectively. The genotype factor directly influences the performance of gibberellic acid in Musa wild species, and adjustments are necessary in the protocols to obtain higher germination and emergence rates for in vitro and in vivo cultures.