Development of novel chloroplast microsatellite markers for Dendrobium officinale, and cross-amplification in other Dendrobium species (Orchidaceae)

Nine pairs of polymorphic chloroplast microsatellite primers were developed for Dendrobium officinale Kimura et Migo, an endangered herb. Levels of polymorphism were tested across a total of 55 individuals from four natural populations (12–15 individuals per population). Allele numbers varied from two to four per locus, while the number of haplotypes ranged from four to six per population. Transferability of the nine polymorphic chloroplast microsatellite primers was checked on an additional set of 51 Dendrobium individuals (belonging to 17 different species). Three markers could be transferable to all the species tested, while the remaining six markers successfully cross-amplified in most species tested. Moreover, polymorphism of the nine chloroplast microsatellite primers was tested across Dendrobium moniliforme (L.) Sw. and Dendrobium loddigesii Rolfe. All of them were polymorphic in D. moniliforme, while seven of which were polymorphic in D. loddigesii. These polymorphic chloroplast microsatellite primers developed for D. officinale will be a useful tool for the study of genetic diversity, population genetic structure, evolution of D. officinale and establishment of effective conservation strategies.