Genetic analysis for identification, genomic template stability in hybrids and barcodes of the Vanda species (Orchidaceae) of Thailand

Abstract

Molecular data supporting morphological characters for identification and specific markers for ornamental Vanda species in Thailand can be achieved for economic means. The ten native Thai species that have been explored and identified are Vanda bensonii, Vanda brunnea, Vanda coerulea, Vanda coerulescens, Vanda denisoniana, Vanda pumila, Vanda lilacina, Vanda liouvillei, Vanda testacea and Vanda tessellata. Three unidentified species (Vanda sp. 1, Vanda sp. 2 and Vanda sp. 3) have been discovered. In addition, three hybrids, hybrid 1 (maternal A × Vanda tessellata), hybrid 2 (Vanda denisoniana × Vanda bensonii), and hybrid 3 (maternal B × paternal C), and two transferred species, Holcoglossum kimballianum (previously Vanda kimballiana) and Papilionanthe teres (previously Vanda teres) were included in genetic analysis by dendrogram constructed from random amplified polymorphic deoxyribonucleic acid (DNA) (RAPD) markers. The results indicate that identical species showed monophyletic group and genetic distances (D) that were between 0.15 to 0.17 which lead to the identification of Vanda, sp. 1 as Vanda bensonii and Vanda sp. 2 as Vanda brunnea because different species give D as higher as 0.20 to 0.40 with divided ancestors. Genomic template stability (GTS) test of hybrids were calculated indicating the percentage of descendant characteristics from parents. The GTS values of hybrid 2 compared with maternal and paternal were 32.88 and 36.62, respectively. Regarding hybrid 1 and 3 for which maternal and / or paternal are unclear, the GTS values when compared to other identified species ranged from 20.34 to 36.84 and 23.19 to 45.98, respectively. Finally, the barcodes of all wild studied species were done by two core barcodes and the tag sequences were tested for nucleotide variations of 0.005 to 0.076 in matK and 0.007 to 0.040 in rbcL regions. The sequences were deposited in GenBank database with accession numbers.

Key words: Genetic analysis, genomic template stability, matK, rbcL, Orchidaceae, Vand,.