Karyotype Analysis of Some Species of Phalaenopsis

Abstract

The karyotypes of the following 9 species of Phalaenopsis (Orchidaceae) were analyzed: P. amabilis var. grandiflora, P. schilleriana, P. lindenii P. equestris, P. luddemanniana, P. luddemanniana var. ochracea. P. boxallii, P. mannii, P. violacea, and P. pulcherrima (Dorites pulcherrima). The first 6 species, which are native to the Philippines, had small chromosomes and relatively symmetrical karyotypes. There were recognizable differences in karyotypes among the species belonging to different sections. The latter three extra-Philippine species had chromosomes that were 2 to 3 times larger than those of the Philippine species. Their karyotypes were less symmetrical with a larger number of sub-terminal chromosomes, and/or with larger differences in size between chromosomes of the same set. On the basis of karyotypes, some aspects of taxonomy and evolution of Phalaenopsis were discussed.