Phenotypic Traits, SSR Core Primer Screening, and Genetic Diversity Analysis of Toxicodendron vernicifluum From...

Yunnan Province in China, with its unique natural conditions, has nurtured abundant yet fragile biodiversity resources. The Toxicodendron vernicifluum is one of the important tree species in Yunnan, valued for its ecological, economic, and medicinal significance. However, due to a lack of related research and limited germplasm resources, breeding and propagation of the T. vernicifluum have lagged behind other tree species. To address this shortcoming, we collected 36 samples of T. vernicifluum germplasm from six representative populations in different regions of Yunnan Province. Combining phenotypic traits, we used 24 selected primer pairs to analyze the genetic diversity and genetic structure of all T. vernicifluum samples. The results showed that seeds from the NLS and ZYG populations performed best. Among all traits, seed length exhibited the greatest variation and highest plasticity. The average values for the Shannon information index (I), expected heterozygosity (He), and polymorphism information content (PIC) of the 24 loci were 0.377, 0.230, and 0.257, respectively, while the average inbreeding coefficient within populations (Fis) was -0.103 (Fis > 0). The ZYG population showed the highest genetic diversity, indicating that the T. vernicifluum has accumulated a large amount of genetic variation during its long-term evolution. AMOVA analysis revealed that 47% of the genetic variation originated within populations. The 36 T. vernicifluum families were divided into three groups, and the six populations were subdivided into three subgroups. This study, based on phenotypic traits and SSR molecular markers, analyzes the genetic diversity of T. vernicifluum resources from different provenances in Yunnan Province, providing a theoretical reference for discovering elite genetic resources and selecting hybrid parents for T. vernicifluum breeding.