Construction of molecular identity card for cultivated Dendrobium officinale in Guizhou Province

To establish a molecular identity card for Dendrobium officinale, providing a scientific basis for the breeding, utilization, standardized production, and quality traceability of cultivated varieties in Guizhou Province. Based on the published genome sequence of Dendrobium officinale, Simple Sequence Repeat (SSR) loci were identified using MISA (MicroSatellite identification tool) software, and SSR molecular markers were designed via Primer 3. Randomly selected primers were used for genetic analysis of cultivated Dendrobium officinale from Guizhou. Amplified fragments were digitally encoded and combined with supplementary information such as origin to construct a Quick Response (QR) molecular identity card. A total of 1,361,061 SSR markers were developed, with an average of 136 per scaffold. Mononucleotide repeats were the dominant motif (63.55%), among which (A) and (T) types accounted for 95.85%. Dinucleotide repeats constituted 11.62% of all SSR loci. Among 40 randomly selected primers, 27 were polymorphic, generating 127 polymorphic bands with a polymorphism rate of 96.27%. Genetic diversity analysis revealed rich genetic diversity in the tested materials. Cluster analysis divided the samples into four groups, based on which a molecular identity card for Guizhou cultivated Dendrobium officinale was successfully constructed. The SSR markers developed in this study exhibit high polymorphism and are suitable for genetic analysis of Dendrobium officinale. The constructed molecular identity card is of significant importance for ensuring the healthy development of the Dendrobium officinale industry in Guizhou.