FALL 2008 Volume 1, Issue 3 EDITORS: ANDY ALLEN Extension Viticulturist THE MIDWEST WINEGROWER [email protected] REBECCA FORD QUARTERLY NEWSLETTER Extension Enologist virus indicator grapevines, V. vinifera ‘Cabernet IN THIS ISSUE: Grapevine fanleaf virus, Tomato Franc’, V. vinifera ‘Baco Blanc’, and hybrid ‘LN- GRAPEVINE 1 33’. Vein-clearing appeared on all grafted vines F ANLEAF VIRUS, ringspot virus and Grapevine although grafted LN-33 showed very mild vein- T OMATO RINGSPOT rupestris stem-pitting associated clearing. No visible symptoms were observed on VIRUS AND GRAPE- virus are present in Chardonnay herbaceous plants Chenopodium quinoa, Nico- VINE RUPESTRIS tiana benthamiana, cucumber, tomato, pepper, STEM -PITTING ASSO- with a severe vein-clearing dis- and cowpea after mechanical inoculation with CIATED VIRUS ARE ease leaf sap of diseased Chardonnay vines. This new disease of Chardonnay is tentatively named as PRESENT IN CHAR- ‘grapevine vein-clearing disease’. DONNAY WITH A Shaista Lunden1, Baozhong Meng2, John Avery, SEVERE VEIN- Jr.1 and Wenping Qiu1 ELISA tests failed to detect the nepo- CLEARING DISEASE 1 Department of Agriculture, Missouri State Uni- viruses Tomato ringspot virus (ToRSV), Tobacco versity, Mountain Grove, MO 65711, USA GRAPEVINE VIRUS 3 ringspot virus, Arabis mosaic virus, and peach 2 Department of Molecular and Cellular Biology, SURVEY UNDERWAY rosette mosaic virus as well as Grapevine University of Guelph, 50 Stone Road East, IN MISSOURI leafroll-associated virus 3. Through reverse- Guelph, Ontario, Canada N1G 2W1 transcription polymerase chain reaction (RT- A METHOD FOR 3 PCR) using degenerate primers for detecting A severe disease was observed on the SCREENING FOR H2S grapevine nepoviruses, we detected the presence grape variety Vitis vinifera ‘Chardonnay’ in a two AND MERCPTANS of Grapevine fanleaf virus (GFLV)-specific -acre vineyard in Missouri (Qiu et al. 2007). AND DMDS sequences (Qiu et al. 2007). We then conducted More than 90% of vines were affected. Symp- RT-PCR to determine whether other members of MANAGING THE 4 toms resembled those caused by virus-like patho- the Nepovirus genus as well as viruses that VINEYARD IN THE gens, including short internodes of zigzagged belong to different taxonomic groups were also POSTHARVEST PE- growth, deformed leaves with a mosaic pattern of present in the infected Chardonnay. Using virus- RIOD dark green and light yellow tissue, vigor decline, specific primers, we detected ToRSV and Grape- small clusters, and few fruits. The vineyard FEDERAL CROP IN- 6 vine rupestris stem pitting-associated virus became unprofitable 10 years after planting, and SURANCE AVAILABLE (GRSPaV). Electron microscopic observations hence the vines were removed and destroyed in FROM USDA-RMA provided evidence that nepovirus-like particles 2007. were present in infected grapevines. To investi- Because abnormal symptoms could be gate if the three viruses were simultaneously caused by adverse environmental conditions or NON-INSURED CROP 7 present in single vines, we sampled leaves with other external factors, hardwood cuttings of DISASTER SSSIS- severe vein-clearing symptoms from three indi- symptomatic vines were collected and grown in TANCE PROGRAM vidual vines and performed RT-PCR assays with potted soil in a greenhouse. New shoots and primers that are specific to the capsid protein ICCVE UPDATE 10 leaves of greenhouse-propagated Chardonnay (CP) genes of GFLV, ToRSV, and GRSPaV. Se- developed similar symptoms. Two buds from the UPCOMING EVENTS 13 quences of each of the virus-specific PCR- original symptomatic vines were grafted onto amplified DNA fragments were also determined each of three asymptomatic Chardonnay vines in and their identities confirmed each specific virus. the greenhouse. Severe deformation of young These results demonstrated that GFLV, ToRSV, leaves and conspicuous vein-clearing on and GRSPaV were co-existent in individual expanded leaves were observed on leaves of the vines. bud-grafted asymptomatic Chardonnay, suggest- The results from this study suggested ing that the causal pathogens are graft- that mixed infection of multiple viruses can result transmissible. Two buds of originally infected in severe disease on a cultivated grape variety. source Chardonnay vines were also grafted onto VISIT OUR WEBSITE: iccve.missouri.edu THE MIDWEST WINEGROWER FALL 2008 Infection of multiple viruses either reveals symptoms or remains symptomless in grape varieties and rootstocks. Acknowledgements. This project was supported by Symptomless scions could develop symptoms once they funding from the Missouri Wine and Grape Board and were grafted onto different rootstocks and planted in from USDA-Viticulture Consortium-East Section under commercial vineyards, such as in the case of the Grape- the Subaward number 51401-8279 through Cornell Uni- vine leafroll associated virus-2 Redglobe virus versity. We thank Keith Striegler for informing us about (Rowhani et al. 2005). Frequent exchanges of grapevine this disease, and the owner and manager of the Chardon- germplasms and grafting of various combinations of nay vineyard for their permission and assistance of col- scions and rootstock create numerous opportunities for lecting samples. different viruses and viral isolates to merge within a single vine. Mixed infection of multiple virus species References frequently aggravates the severity of symptoms in a sin- gle vine. Afterwards, a viral complex will remain and Golino, D. A., and V. Savino. 2008. Certification and perpetuate in the progeny vines via large-scale vegeta- international regulation of plant materials. In Compen- tive propagation. This study presents a typical case sup- dium of Grape Diseases, edited by W. F. Wilcox, W. G. porting that it is imperative to develop a network for Gubler and J. K. Uyemoto. St. Paul, MN: APS Press (in national and international exchange of clean grapevine press). propagation materials (Golino and Savino 2008). Propa- gating certified grapevines will greatly reduce the inci- Qiu, W. P., J. D. Avery, and S. Lunden. 2007. Charac- dences of mixed infections and hence new diseases in terization of a severe virus-like disease in Chardonnay grape growing regions with diverse climatic, environ- grapevines in Missouri. Plant Health Progress online mental and soil conditions. publication, November 19, 2007. Figure 1. Young shoots of virus-affected Chardonnay vines have short, zig-zag internodes and small, mosaic leaves. Major veins of mosaic leaves with green and yellow tissues are translucent when the leaves are held against sunlight. 2 THE MIDWEST WINEGROWER FALL 2008 References Rowhani, A., J. K. Uyemoto, D. A. Golino, and G. P. Martelli. 2005. Pathogen testing and certification of Vi- tis and Prunus species. Ann. Rev. Phytopatho. 43:261- Milkus, B.N. and R.N. Goodman. 1999. A survey of 278. Missouri vineyards for the presence of five grape vi- ruses. Amer. J. Enol. Vitic. 50:133-134. Grapevine virus survey underway in Milkus, B.N. 2001. Incidence of four NEPO viruses in Missouri Missouri vineyards. Amer. J. Enol. Vitic. 52:56-57. Andy Allen A method for screening for H2S, Extension Viticulture Associate Mercaptans and DMDS University of Missouri Institute for Continental Climate Viticulture and Enology Rebecca Ford-Kapoor Extension Enology Associate As part of a project funded by the Missouri Life University of Missouri Sciences Trust Fund, members of the ICCVE in coop- Institute for Continental Climate eration with faculty from the Missouri State Fruit Viticulture and Enology Experiment Station are conducting a survey for virus diseases of grapevines and potential nematode vectors in Even the most skilled winemaker has batches of wine several locations around the state. During this first year that for some reason have propensities for the develop- of the three-year project, the focus is on ‘Chardonel’ ment of off aromas. However, the winemaker needs to vineyards known or suspected to have infected vines. be careful not to make unnecessary wine additions. Several mature blocks of ‘Chardonel’ grapevines around Screening wines to discover what exactly the problem the state have experienced declining vigor and produc- with the wine is can prevent unnecessary wine treat- tivity due to suspected virus infection. In late July, coop- ments. erators in the project traveled to several mature ‘Chardonel’ vineyard blocks and collected tissue sam- H2S (hydrogen sulfide) has a characteristic rotten egg ples from both symptomatic and asymptomatic vines aroma (Jackson 2000) and has a sensory threshold of and from wild vines in nearby woods which will be used between 50-80 ppb (Wenzel et al. 1980). Mercaptans in laboratory tests to determine if, how many, and which have a range of aromas including rotten onion, cabbage, viruses may be present. Previous work on Chardonnay burnt rubber, skunky and fecal odors (Jackson 2000; grapevines in Missouri (see companion article on page 1 Zoecklein et al. 1999). Mercaptans have very low of this issue) has determined that a complex of several sensory thresholds, ethyl mercaptan around 1.1 ppb and viruses may be present in a single grapevine. Later this methylmercaptan about 0.2-2ppb (Zoecklein et al. season, soil samples will be collected from these same 1999). DMDS (dimethyl disulfide) arises from the oxi- vineyard blocks to check for the presence of known dation of methyl mercaptan and has an odor of onion or nematode vectors of grapevine viruses. Also as part of cooked cabbage (Zoecklein et al. 1999). the project,