In general, polyploidy in plants causes an increase in the size ofvegetative structures. This work aimed to compare diploid plants (2n = 2 x =38) and induced tetraploid plants (2n = 4 x = 76) of Dendrobium nobile Lindl. through the evaluation of themorphological characteristics of flowers, leaves and pseudobulbs. We evaluatedthe parameters height and diameter of pseudobulbs; width and length of leavesand flowers (sepals, petals and labella); and diameter of flowers. The inducedpolyploidization resulted in the increasing the number of internodes (19.9%)and floral pieces, with greater height of the flower (4.5%) and width of thelip (18.5%) decrease in the number of flowers per pseudobulb (40.9%) and thediameter of the pseudobulb (64.9%) and delayed flowering.
Orchid; chromosome doubling; colchicine; tetraploidy
