Twenty-four treatment combinations among genotypes, physical medium composition and plant growth regulator levels of naphthaleneacetic acid (NAA) and 6-benzilaminopurine (BAP) were evaluated in order to identify the most efficient combination for the pineapple micropropagation in the laboratory of the Universidade Federal de Santa Catarina, Brazil, from 1993 to 1996. During seven weeks after the inoculation, the regeneration rate behaved as a quadratic function for most of the combinations. In one case (liquid medium, cultivar Primavera), the response followed a linear model. Among the treatments, the most efficient was the combination of MS (Murashige & Skoog, 1962) liquid medium with NAA (2.7 µM) and BAP (4.4 µM) which produced 19.7 shoot/explant, a significant deviation from the mean average (12 shoot/explant).The genotypic effect exhibited by two genotypes (Perolera and Primavera), expressed in terms of regeneration rate, was intermediary between the effect of the plant growth regulators levels and the physical medium constitution. The best treatment combination was tested in 17 other genotypes colected in the Santa Catarina State. In average, it was produced 15.3 shoot/explant, five weeks after the explant inoculation, 40% of which showing height near 3 cm. When submitted to acclimatization, 95.5% of the plantlets survived.
tissue culture; organ culture; regeneration rate; mass clonal propagation; Ananas comosus
