Objective This study employed iPBS molecular marker technology to analyze the genetic diversity and genetic differentiation relationships among 32 Dendrobium linawianum germplasm resources from different regions. Methods A “0, 1” matrix was constructed using Excel 2016, and the genetic similarity coefficient (G_s) was calculated using NTSYS-pc 2.10e to construct a UPGMA cluster dendrogram. Additionally, various genetic diversity indices were calculated using Popgene 1.32. Results A total of 84 clear bands were amplified from the six selected iPBS primers, including 76 polymorphic bands, with a polymorphism rate of 90.48% and an average polymorphism information content (PIC) of 0.46, indicating high polymorphism of the iPBS primers. The genetic similarity coefficients ranged from 0.547 6 to 0.965 5, with an average of 0.766 8. At a genetic similarity coefficient of 0.732, the 32 germplasm samples were classified into four populations. The average observed allele number (N_a), average effective allele number (N_e), Nei's genetic diversity index (h), and Shannon diversity information index (I) were 1.631 0, 1.381 6, 0.219 0, and 0.326 7, respectively. Genetic structure analysis revealed that the genetic diversity (H_t), gene differentiation coefficients (H_s) among populations, and genetic differentiation coefficients (G_st) were 0.281 3, 0.219 0, and 0.221 3, respectively. Genetic variation among populations accounted for 22.13% of total variation, while genetic variation within populations accounted for 77.87%, indicating that genetic variation was primarily derived from within populations. Furthermore, DNA fingerprinting of 32 germplasm resources was successfully constructed based on 19 polymorphic loci with six primers, which provided a reference for the classification and identification of D. linawianum. Conclusion The genetic diversity of D. linawianum was significantly lower between populations than within populations, and the genetic variation was mainly within populations. The genetic differentiation characteristics of germplasm resources are significantly correlated with their geographical distribution patterns. This study not only elucidates the genetic relationships among different germplasm of D. linawianum and the characteristics of population genetic diversity, but also provides an important theoretical basis for the subsequent scientific conservation and sustainable utilization of D. linawianum germplasm resources.

Dendrobium linawianum Rchb. f.  /  germplasm resources  /  iPBS markers  /  phylogenetic relationships  /  genetic diversity