Nuclear DNA contents of Phalaenopsis sp and Doritis pulcherrima

Nuclear DNA contents were estimated by flow cytometry in 18 Phalaenopsis Bl ume species and Doritis pulcherrima Lindl. DNA amounts differed 6.07-fold, from 2.74 pg/diploid nuclear DNA content (2C) in P. sanderiana Rchb.f. to 1 6.61 pg/2C in P. parishii Rchb.f. Nuclear DNA contents of P. aphrodite Rchb .f. clones, W01-38 (2n = 2x = 38), W01-41 (2n = 3x = 57), and W01-22 (2n = 4x = 76), displayed a linear relationship with their chromosome numbers, in dicating the accuracy of flow cytometry. Our results also suggest that the 2C-values of the Phalaenopsis sp. correlate with their chromosome sizes. Th e comparative analyses of DNA contents may provide information to molecular geneticists and systematists for genome analysis in Phalaenopsis. Endoredu plication was found in various tissues of P. equestris at different levels. The highest degree of endoreduplication in P. equestris was detected in le aves.