Etiolated nodal segments are used for micropropagation and conservation of the genetic identity of several crops. The present study evaluated this method for the multiplication of the pineapple hybrid PE x SC-52. Plantlet stems produced in vitro were inoculated in test tubes containing MS nutrient medium and maintained in darkness for 60 days for etiolation. Three treatments were used with growth-regulator free MS medium; NAA at 1.86 mg/L, and IAA at 1.75 mg/L, with five repetitions and ten explants per repetition. There was no difference among the treatments in the number of etiolated shoots, per explant. However, NAA and IAA, after 35 days, produced a greater number of nodes per shoot, and NAA was the most efficient after 60 days. Etiolated shoots were placed horizontally in Petri dishes containing MS medium and incubated in the presence of light. Four treatments were used for the regeneration of plantlet growth-regulator free MS medium; BAP at 2 mg/L; NAA at 1.86 mg/L + BAP at 2 mg/L, and KIN at 5 mg/L with four repetitions and seven etiolated shoots per repetition. BAP promoted the largest number of regenerated plantlets per shoot and per node, with an average of 10.4 plantlets per shoot after 30 days.
Ananas comosus; in vitro culture; micropropagation; plant propagation
