Status of Rubus germplasm at the US National Clonal Germplasm Repository in Corvallis, Oregon

The US Department of Agriculture (USDA), National Clonal Germplasm Repository (NCGR) is the genebank for Rubus (blackberries, raspberries, and their crop wild relatives) in the United States. The genebank includes 198 species with 2,180 accessions of plants and seeds from 67 countries. The primary collection of heritage cultivars and selections are maintained clonally as containerized plants in greenhouses and screenhouses. Propagules from foundation material are distributed for research purposes as root cuttings with dormant buds, crown divisions, or tip layers, depending on crop requirements and season. Several projects concerning Rubus genetic and genomic resources are being conducted including 1) determining phylogenetic relationships of 96 Rubus species representatives and cultivars using target capture sequencing; 2) use of a DNA fingerprinting test to establish genetic profiles, confirm identity, and establish parentage in blackberry; 3) determination of sequence variation in genes that control red raspberry resistance to powdery mildew; and 4) identification of the genes responsible for resistance to aphid feeding in black raspberry to reduce the occurrence of the aphid-borne Black raspberry necrosis virus complex in new cultivars. The availability of wide genetic diversity in Rubus at the NCGR demonstrates the usefulness of this collection in advancing research to benefit scientists, plant breeders, growers, and consumers of these berry crops.