Evaluation of the growth traits of Toxicodendron vernicifluum progeny based on their genetic groups assigned using new microsatellite markers

Toxicodendron vernicifluum (Stokes) F. A. Barkley is a tree species cultivated in Japan for production of Japanese lacquer. To facilitate the low-cost improvement of T. vernicifluum, we developed microsatellite markers for DNA fingerprinting and family and lineage reconstruction. Nine useful microsatellites were developed, with 3 to 23 alleles per locus and an expected heterozygosity of 0.162-0.838 based on a commercially planted population that included 783 offspring. Six clusters were detected in this population based on the Bayesian clustering method, and 93 half-sib families were identified using parentage and sibship assignment analysis based on a maximum likelihood method. Many members (40-96%) of large (≥10) half-sib families included specific clusters, and members from different families included the same clusters. The cluster effect for tree height was more significant than the half-sib family effect using a linear mixed model, although these effects were not significant for other traits (diameter at breast height and number of forked trunks). Based on the findings from pedigree reconstruction, backward selection for tree height seems possible. We discuss the direction of research for improving T. vernicifluum using our proposed approach.