Conservation and characterization of the USDA national pear collection

Authors: Bassil, Nahla; Reinhold Aboosaie, Lauri; ZURN, JASON - Kansas State University; POSTMAN, JOSEPH - Retired ARS Employee; Gilmore, Barbara; Flores, Gabriel; Nyberg, April; King, Ryan; DRISKILL, MANDIE - University Of Oregon; Olson, Jane; Volk, Gayle; Jenderek, Maria; MONTANARI, SARA - New Zealand Institute Of Plant & Food Research; CHAGNE, DAVID - New Zealand Institute Of Plant & Food Research; BUS, VINCENT - New Zealand Institute Of Plant & Food Research; BREWER, LESTER - New Zealand Institute Of Plant & Food Research; Dardick, Christopher - Chris; Gottschalk, Christopher; DUREL, CHARLES-ERIC - Inrae; DENANCE, CAROLINE - Inrae

Submitted to: Acta Horticulturae
Publication Type: Abstract Only
Publication Acceptance Date: 1/29/2022
Publication Date: 8/18/2022
Citation: Bassil, N.V., Reinhold Aboosaie, L.A., Zurn, J., Postman, J., Gilmore, B.S., Flores, G.N., Nyberg, A.M., King, R., Driskill, M., Olson, J.E., Volk, G.M., Jenderek, M.M., Montanari, S., Chagne, D., Bus, V., Brewer, L., Dardick, C.D., Gottschalk, C.C., Durel, C., Denance, C. 2022. Conservation and characterization of the USDA national pear collection. Acta Horticulturae.

Interpretive Summary: The U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS) conserves 2,378 accessions of pear and 478 pear wild relatives in an orchard at the National Clonal Germplasm Repository (NCGR) in Corvallis, Oregon. In the last five years, the incidence of fireblight has increased in the collection. Accessions known to be susceptible to fireblight are preserved in a secondary backup collection on-site in 25 cm deep (D-cell) containers in screenhouses. In addition, these susceptible genotypes are prioritized for remote backup at the USDA National Laboratory for Genetic Resource Preservation (NLGRP), in Fort Collins, Colorado. DNA markers are used for efficient management of this collection by identifying and eliminating duplicates and mis-labeled trees, and ensuring a diverse collection of true-to-type heritage cultivars and their wild relatives. Further collaborative projects with international pear researchers include comparing the genotypes of important pear cultivars preserved in the US national collection at Corvallis, and across European collections to obtain a global view of heritage pear genetic resources; and developing diagnostic markers for fireblight resistance. Conservation and characterization of pear genetic resources at the NCGR is a global effort and will be discussed at the symposium.

Technical Abstract: The U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS) conserves 2,378 accessions of pear and 478 pear wild relatives in an orchard at the National Clonal Germplasm Repository (NCGR) in Corvallis, Oregon. In the last five years, the incidence of fireblight has increased in the collection. Accessions known to be susceptible to fireblight are preserved in a secondary backup collection on-site in 25 cm deep (D-cell) containers in screenhouses. In addition, these susceptible genotypes are prioritized for remote backup as cryopreserved dormant buds or shoot tips at the USDA National Laboratory for Genetic Resource Preservation (NLGRP), in Fort Collins, Colorado. A 70K single nucleotide polymorphism (SNP) array and two simple sequence repeat (SSR) fingerprinting sets are used for efficient management of this collection by identifying and eliminating duplicates and mis-labeled trees, and ensuring a diverse collection of true-to-type heritage cultivars and their wild relatives. Further collaborative projects with international pear researchers (INRAE, Angers, France and Plant & Food Research, New Zealand) include comparing the SSR-based genotypes of important pear cultivars preserved in the US national collection at Corvallis, and across European collections to obtain a global view of heritage pear genetic resources; and developing diagnostic markers for fireblight resistance. Conservation and characterization of pear genetic resources at the NCGR is a global effort and will be discussed at the symposium.