New sources of eastern filbert blight resistance from Turkey map to Linkage Group 2

Fecha de publicación: 10/12/2022
Fuente: ISHS (International Society for Horticultural Science)
Post date: Saturday 10 December 2022
Author:
ISHS Secretariat

Brianna Heilsnis is a Ph.D student in the Department of Horticulture at Oregon State University, Corvallis, Oregon, USA, under the supervision of Dr. Shawn Mehlenbacher in the Hazelnut Breeding and Genetics lab. Her research is focused on host plant resistance to eastern filbert blight (EFB), which is caused by the ascomycete Anisogramma anomala. Currently, the hazelnut industry in Oregon is protected by a dominant allele on linkage group (LG) 6, originally discovered in the European hazelnut, Corylus avellana ‘Gasaway’. However, when tested against other A. anomala isolates from New Jersey, ‘Gasaway’ resistance breaks down. In preparation for either a second accidental introduction of A. anomala into Oregon or a mutation of the current isolate, the Hazelnut Breeding Program has been searching for additional sources of resistance. Since the resistance gene in ‘Gasaway’ was first recognized, the program has identified 122 sources of very high resistance, 27 of which have been mapped and are located on LG2, 6, or 7. Once identified, the subsequent goal of the program is to pyramid resistance genes for durable protection against potentially new races of A. anomala. This project evaluated three new hazelnut genotypes from Turkey (OSU 1229.082, OSU 1240.131, and OSU 1289.028) which showed no signs of disease after structure or field inoculations. All three were then crossed with susceptible parents and their offspring inoculated with A. anomala (Oregon isolate) and evaluated for canker development. Segregation ratios from the progeny indicated all three genotypes had single dominant resistance. Disease phenotype scores, collected 20 months after inoculations, were correlated with simple sequence repeat markers from LG2, 6, and 7 resistance loci, and any loci with marker correlation coefficients greater than 0.5 were further investigated. Each of the three genotypes mapped to the same region on LG2, but sequencing is required to determine if they are the same gene. This study doubled the number of known LG2 resistant sources and increased the germplasm diversity with which to pyramid resistance genes in future crosses.
Brianna Heilsnis won the ISHS Young Minds Award for the best poster presentation at the X International Congress on Hazelnut in USA in September 2022.
Brianna Heilsnis, Department of Horticulture, 4017 Agriculture and Life Sciences Building, Corvallis, OR 97331, USA, e-mail: brianna.heilsnis@oregonstate.edu
The article is available in Chronica HorticulturaeTags: hazelnutCategories: Young Minds Award Winners