Morphological effects of induced polyploidy in Dendrobium nobile Lindl. (Orchidaceae)

Abstract

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.