Evaluating Chemical Fingerprinting as a Tool to Rapidly Screen Hybrid Chestnut for Disease Resistance

Screening chestnut hybrids for disease resistance is intensive because trees must be inoculated with either Cryphonectria parasitica (causal agent of chestnut blight) or Phytophthora cinnamomi (causal agent of Phytophthora root rot). Chemotyping (i.e. chemically phenotyping or fingerprinting) trees and identifying chemical markers associated with resistance is an alternative method that could be used to screen trees rapidly. The goals of this study are to chemotype inter-specific hybrids, to identify potential markers of disease resistance, and to develop and validate predictive models that can be used to prescreen hybrids for resistance prior to planting in seed orchards. Results generated from our experiment in 2015 – 2016, indicate that chemotypic differences between hybrids exist and in some instances can be used to distinguish between hybrids that vary in disease susceptibility. Additional evaluations, particularly of larger families and at earlier stages of intercrossing (e.g. BC F ) are needed to develop and validate more robust and reliable predictive models.