Upatham Meesawat, Theera Srisawat, Ladda Eksomtramage, and Kamnoon Kanchanapoom

pp. 227 - 280

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 pg to 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 the
presence of exogenous plant growth regulators.