Markers for ornamental traits in Phalaenopsis orchids

Population structure, linkage disequilibrium and association mapping

authored by: I. Gawenda, A. Schröder-Lorenz, T. Debener
Abstract: Although Phalaenopsis orchids are among the most economically important potted plants, little is known about either the genetic diversity among varieties or the genetic complexity of key ornamental traits. Therefore, we analysed the genetic diversity of a broad collection of Phalaenopsis varieties and selected wild species by means of molecular markers. The marker data were used to obtain genetic distances, estimates of the degree of linkage disequilibrium and population structure for the genotypes under study. With a total of 492 markers, the genotypes clustered according to their horticultural classification (for example, old hybrids vs. more recent hybrids) but not according to their origin, indicating extensive exchange of germplasm among breeders. Linkage disequilibrium was found to decrease relatively slowly, most likely due to the small number of generations that have occurred since the first hybrids were generated. Based on the most likely estimates for the population structure (ranging from 10 to 12 subpopulations), associations between ornamental traits like flower size, flower colour, flower type, flower texture, stem length and leaf shape were calculated. These results can now serve as starting points for detailed analyses of the genetic architecture of these traits.
Organisation(s): Institute of Plant Genetics
Section Molecular Plant Breeding
External Organisation(s): University of Hohenheim
Bock Bio Science GmbH
Type: Article
Journal: Molecular breeding
Volume: 30
Pages: 305-316
No. of pages: 12
ISSN: 1380-3743
Publication date: 06.2012
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Biotechnology, Molecular Biology, Agronomy and Crop Science, Genetics, Plant Science
Electronic version(s): https://doi.org/10.1007/s11032-011-9620-8 (Access: Unknown)