Chromosome synteny of genetic linkage groups 7 and 13 between Phalaenopsis aphrodite subsp formosana and Phalaenopsis equestris

Abstract

There are two native Phalaenopsis species in Taiwan Phalaenopsis aphrodite subsp formosana and P equestris and both are important breeding parents Phalaenopsis genome research can contribute to systematic breeding Cytogenetic studies such as genetic linkage maps and karyotype analysis play an important role in breeding but the cytogenetic related research of Phalaenopsis is still quite little In this study we integrated two genetic linkage groups 7 13 EFS and 5S rDNA genes of P aphrodite to high-resolution pachytene chromosomes of P equestris by using comparative fluorescence in situ hybridization (FISH) technique Our results show that the genetic linkage group 13 (LG13) and EFS are located on the chromosome 13 of P aphrodite and on the chromosome 16 of P equestris The genetic linkage group 7 (LG07) is located on the chromosome 7 of P aphrodite and on the chromosome 3 of P equestris The 5S ribosomal DNA (5S rDNA) has two loci in P aphrodite located on chromosomes 6 and 12 and only one locus in P equestris located on chromosome 12 These results indicate that the locations of our selected two genetic linkage groups are conserved on chromosomes between P aphrodite and P equestris The 5S ribosomal DNA located in the short-arm heterochromatin and euchromatin junction region in both species In both species EFS is located at the end of the long arm and has a relative positional exchange with scaffold_46 between the two species Our current results provide cytogenetic evolutionary and breeding studies in Phalaenopsis orchids

Date of Award	2018 Aug 30
Original language	English
Supervisor	Song-Bin Chang (Supervisor)