Molecular evaluation of aphid-resistant black raspberry germplasm for improved durability in black and red raspberry

Authors: Bushakra, Jill; DOSSETT, MICHAEL - British Columbia Blueberry Council; Lee, Jana; Lee, Jungmin; Bassil, Nahla; Finn, Chad

Submitted to: American Society of Horticulture Science Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 6/15/2015
Publication Date: 6/15/2015
Citation: Bushakra, J., Dossett, M., Lee, J.C., Lee, J., Bassil, N.V., Finn, C.E. 2015. Molecular evaluation of aphid-resistant black raspberry germplasm for improved durability in black and red raspberry [abstract]. American Society of Horticulture Science Meeting. 2015 American Society for Horticultural Science Annual Conference.

Interpretive Summary: Over the last century, the black raspberry (Rubus occidentalis) industry in the U.S. has undergone a slow contraction because of a lack of adapted and disease resistant cultivars. The Pacific Northwest is the major black raspberry production region in North America, with the value of $9.6 million production in Oregon on over 1,650 acres. Continuing research on health benefits of a diet rich in phytonutrients, and black raspberries in particular, has led to a resurgence of interest in this fruit and a renewal of breeding. While the crop faces numerous challenges in the PNW that are being addressed with breeding and genomics, one of the major problems is the severe impact Black raspberry necrosis virus has on plant health and the industry’s viability. BRNV is an aphid-borne virus that, in the standard cultivar (Munger), causes a rapid decline in vigor leading to plant death. In addition, aphid resistance is important to the red raspberry industry in Washington and Oregon, where aphid-vectored viruses are a major component of a crumbly fruit disease complex. Three sources of aphid resistance were identified in wild black raspberry germplasm collected from Ontario, Canada, Maine, and Michigan. The evaluation of the aphid resistance sources are being studied on three full-sib black raspberry populations designated ORUS 4304 (ME), ORUS 4305 (ON), and ORUS 4812 (MI). A major focus of this study is to better characterize and develop DNA-based markers that can be used in breeding programs to enable pyramiding of different sources of resistance in new breeding material to ultimately provide resistance that will not easily be overcome by the aphids. At present, the ability to combine these sources effectively is limited by a lack of knowledge regarding their mechanisms and linkage. To date, 17 black raspberry populations with single and combinations of sources of aphid resistance have been phenotyped. Preliminary molecular evaluation for aphid susceptibility of the 17 populations suggest two unique genes in those with sources of resistance from Michigan and Ontario.

Technical Abstract: Over the last century, the black raspberry (Rubus occidentalis) industry in the U.S. has undergone a slow contraction because of a lack of adapted and disease resistant cultivars. The Pacific Northwest is the major black raspberry production region in North America, with the value of $9.6 million production in Oregon on over 1,650 acres. Continuing research on health benefits of a diet rich in phytonutrients, and black raspberries in particular, has led to a resurgence of interest in this fruit and a renewal of breeding. While the crop faces numerous challenges in the PNW that are being addressed with breeding and genomics, one of the major problems is the severe impact Black raspberry necrosis virus has on plant health and the industry’s viability. BRNV is an aphid-borne virus that, in the standard cultivar (Munger), causes a rapid decline in vigor leading to plant death. In addition, aphid resistance is important to the red raspberry industry in Washington and Oregon, where aphid-vectored viruses are a major component of a crumbly fruit disease complex. Three sources of aphid resistance were identified in wild black raspberry germplasm collected from Ontario, Canada, Maine, and Michigan. The evaluation of the aphid resistance sources are being studied on three full-sib black raspberry populations designated ORUS 4304 (ME), ORUS 4305 (ON), and ORUS 4812 (MI). A major focus of this study is to better characterize and develop DNA-based markers that can be used in breeding programs to enable pyramiding of different sources of resistance in new breeding material to ultimately provide resistance that will not easily be overcome by the aphids. At present, the ability to combine these sources effectively is limited by a lack of knowledge regarding their mechanisms and linkage. To date, 17 black raspberry populations with single and combinations of sources of aphid resistance have been phenotyped. Preliminary molecular evaluation for aphid susceptibility of the 17 populations suggest two unique genes in those with sources of resistance from Michigan and Ontario.