Morphological and cytogenetic evaluation of Phalaenopsis cultivars

The genus Phalaenopsis (family Orchidaceae) comprises approximately 66 species and is a popular choice for potted ornamental plants. Recent years have witnessed increased commercial demand for a wide range of Phalaenopsis hybrids with various flower colors, shapes, fragrances, and increased tolerance to biotic and abiotic stress. Interspecific and intergeneric hybridization between different sections or subgenera has been widely used to develop cultivars with novel traits. As a consequence of these hybridizations, polyploidy is frequently observed in Phalaenopsis, as indicated by a wide range of chromosome numbers. Considering the dearth of information on Phalaenopsis species and cultivars used in breeding, morphological, cytogenetic, and genomic studies are essential for providing plant scientists and breeders with critical knowledge. In this study, the morphological characteristics, and chromosomal compositions of 35 Phalaenopsis standard and novelty cultivars were evaluated. All examined Phalaenopsis cultivars possessed unique phenotypic characteristics, and cytogenetic analysis revealed that most cultivars were aneuploids with hyper- and hypoploid chromosome numbers. All standard cultivars exhibited small, uniformly sized chromosomes, whereas certain novelty cultivars possessed asymmetrical small, medium, and large chromosomes. The results of this study provide valuable insights for breeders aiming to devise efficient Phalaenopsis breeding programs. Clinical trial number Not applicable.