‘Norton’ Grapevine is Resistant to Grapevine Vein Clearing Virus Wenping Qiu, Sylvia M Petersen, Susanne Howard, Xiangmei Zhang, and Kai Qiao Center for Grapevine Biotechnology, The Darr College of Agriculture, Missouri State University Virus Resistance in ❖ Identification of resistance genes Grapevines to viruses in Vitis rarely reported

❖ Resistance to viruses highly 2 desirable trait GVCV ❖ DNA virus ❖ Vein- endemic to clearing, our area stunted vine,

death of 3 infected vine

❖ Deformed berries GVCV ❖ Native ❖ Discovered A. ❖ Found grape grapevines cordata as aphids (A. host the viral reservoir illinoisensis)

virus ≈ 10% ≈ 34% are a vector 4 (19/186) (142/413) GVCV ❖ Native ❖ Cultivated grapevines grapevines V. cinerea Chardonel

V. vulpina Vidal blanc 5 V. rupestris Cabernet Sauvignon V. palmata Traminette Chardonnay Valvin Muscat What about Norton?

6 The Wonders Resistant to: of Norton ❖ Downy mildew 7 ❖ Powdery mildew

❖ Bunch rot Norton and GVCV 9 Survey of GVCV in Foundation Chardonel Vidal Blanc Norton Vineyard 10 Total 19% 30% 0 Norton scion on GVCV- GVCV-infected infected Chardonel Chardonel on Norton

Infected Infected Chardonel Norton 11 Chardonel Norton Plant 1 Plant 2 Plant 3 Plant 4 Plant 5 Plant 6

9 months 2 years 10 months 10 months 3 years 2 years M (GV x CS) (N x GV) (N x GV) (N x GV)(GV x N)(Vig x GV) + -

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GVCV-specific 442 bp and 835 bp fragments by PCR. The 16S rRNA-specific 105 bp fragment baseline for DNA quality. CS-‘Cabernet sauvignon’, GV-GVCV infected ‘Chardonel’, N-‘Norton’, Vig- ‘Vignoles’ (scion x rootstock). RNA for ❖ Required part ❖ Part of plant a DNA of GVCV defense virus? replication against 13 cycle viruses RNAseq ❖ Next-generation technology that determines sequence and quantity of all RNA present in plant sample 14

❖ We used RNAseq to determine presence of GVCV RNAseq GV x CS N x GV GV x N scions and GVCV genome 100% GVCV genome GVCV genome 100% rootstocks assembled from not assembled assembled from small RNAs in GVCV- from Norton GVCV-infected 15 infected Chardonel scion. GVCV Chardonel scion. scion and genome 100% GVCV genome not Cabernet Sauvignon assembled from assembled from GVCV-infected Norton Chardonel Norton as Cabernet Resistant parent Norton sauvignon progeny? 16 Quality wine grapes? Norton as ❖ 2006- Planted 100 parent crosses of Norton and Cabernet Sauvignon 17 Norton as ❖ 2019-Pathogen parent

resistance 18 experiments on progeny Norton as ❖ Over 200 grafts of progeny and a parent GVCV-infected Chardonel

❖ Surviving vines assayed 19 ❖ 61 progeny susceptible to GVCV via graft transmission

❖ 20 resistant PCR assay of Norton progeny grafted with GVCV infected Chardonel

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+ -

GVCV-specific 442 bp and 835 bp fragments by PCR The 16S rRNA-specific 105 bp fragment baseline for DNA quality CN; Cabernet Sauvignon mother crossed with Norton Management of viruses Prevention

❖ Virus free planting stock

❖ Limit vectors 21

❖ Control inoculum sources Management of viruses

❖ Resistance to 22 grapevine viruses

Photo: Wendy McFadden, (OMAFRA) Norton Vignoles Chambourcin Chardonel Vidal Blanc 23 Traminette Cayuga White Vivant Orion NC-6 Conclusion ❖ Norton is resistant to GVCV

❖ Evidence via field studies, grafting, PCR and RNAseq 24 ❖ Preliminary progeny evaluation shows resistance likely a heritable trait from Norton Future research ❖ Investigate whether Norton is resistant or tolerant to other 25 important grapevine viruses Future research ❖ Explore breeding to confer virus resistance to progeny 26

❖ Discern mechanism(s) of Norton’s resistance THANK YOU! 27