Chromosome Analysis of Phalaenopsis Yellow Cultivars

In Phalaenopsis, interspecific hybridization has been broadly used for breeding cultivars with new traits of flower colors. Yellow pigments in Phalaenopsis cultivars naturally are derived from the diploid species in subgenus Polychilos, including P. amboinensis, P. fasciata, P. lueddemanniana and P. venosa, etc. Commercial cultivars of yellow Phalaenopsis were made by crossing the diploid species in subgenus Polychilos with tetraploid standard-type cultivars, and this often resulted in the formation of triploid progenies. Here we review the breeding history of yellow Phalaenopsis cultivars from a cytogenetic perspective. Chromosome analyses indicate polyploidization playing an important role in these breeding programs and reveal different chromosome introgression of section Polychilos species in these yellow cultivars. The cytogenetic data of these cultivars could provide basic knowledge for yellow Phalaenopsis breeding.