Cultivar Identification and Genetic Relatedness among 25 Black Walnut (Juglans nigra L.) Clones Based on Microsatellite Markers

by

Kejia Pang, Keith Woeste, and Charles Michler

Postdoctoral Fellow (KJ), Center for Agroforestry, 203 Natural Resources Bldg., University of Missouri, Columbia, MO; Research Geneticist (KW), and Research Horticulturist (CM), Hardwood Tree Improvement and Regeneration Center, U.S. Forest Service Northern Research Station, Purdue University, West Lafayette, IN. KJ is corresponding author: to contact, email at pangk@missouri.edu.

Abstract – A set of eight microsatellite markers was used to genotype 25 black walnut (Juglans nigra L.) clones within the Purdue University germplasm repository. The identity of 212 ramets was verified using the same eight microsatellite markers. A few trees were mislabeled and corrected as to clone using analysis of microsatellite markers. A genetic dendrogram was constructed to show genetic relatedness among clones. Two more dendrograms, one based on crown architecture traits, and the other on tree size and form traits, were also built and compared with the genetic dendrogram. The genetic dendrogram showed that these eight molecular markers had the ability to distinguish genetically related clones from less related ones. Crown architecture traits and tree size and form traits were able to group genetically related clones together, but less accurate than the genetic matrix.