Songklanakarin Journal of Science and Technology (SJST) (May 2008)
Nuclear DNA content of the pigeon orchid (Dendrobium crumenatum Sw.) with the analysis of flow cytometry
Abstract
Nuclear DNA content for the adult plants grown in a greenhouse and in vitro young plantlets of the pigeon orchid (Dendrobium crumenatum Sw.) was analyzed using flow cytometry. The resulting 2C DNA values ranged from 2.30±0.14 pgto 2.43±0.06 pg. However, nuclear DNA ploidy levels of long-term in vitro plantlets were found to be triploid and tetraploid.These ploidy levels were confirmed by chromosome counting. Tetraploid individuals (2n = 4x = 76) had approximately two times DNA content than diploid (2n = 2x = 38) individuals. This variation may be due to prolonged cultivation and thepresence of exogenous plant growth regulators.