Progress 01/01/09 to 12/31/13

Outputs
Target Audience: The target audiences for this project included scientists,the agricultural industry and consumers.The researchproducts were disseminated to the scientific and greater agricultural community as peer-reviewed articles, conference proceedings or popular articles. ThePI participated in scientificand industry meetingspresenting the research progress of the project and also workshopsproviding hands-on experience with virus diseasesto extension personnel, growers andthe nursery industry. The general public, as consumers benefit from this project because healthyplants produce better quality productwhereas the work from this project allowed forextended sustainableproduction, maximizing grower profitability. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? This project has given the opportunity to five MS and two PhD students to train in the field of virology. It has also provided experince toseven PhD scientists in various areas of virology. How have the results been disseminated to communities of interest? The target audiences for this project included scientists,the agricultural industry and consumers.The researchproducts were disseminated to the scientific and greater agricultural community as peer-reviewed articles, conference proceedings or popular articles. ThePI participated in scientificand industry meetingspresenting the research progress of the project and also workshopsproviding hands-on experience with virus diseasesto extension personnel, growers andthe nursery industry. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Blackberry yellow vein disease and crumbly fruit and decline remain the two most important virus problems for Rubus (blackberry and raspberry) growers across the country. Both diseases are caused virus complexes, the identities of which are not as important as is the sheer number of viruses infecting a plant. The number of viruses associated with the diseases increases continually as is the number of potential vectors in the field. Both diseases have major economic impacts. In the Southeast and because of Blackberry yellow vein disease the approximate lifespan of a field is 5-7 years in contrast to the 20 years that was the normal just a few years ago. The cost of transplanting is well above $6,000/acre and plants are not fully productive for the first two years. The price of fruit from plants affected from crumbly fruit and decline are less than 25% of the price of normal fruit. This project has an economic impact measured in the tens of millions of dollars. Soybean vein necrosis virus (SVNV), the causal agent of Soybean vein necrosis disease is the most widespread virus in the US. Symptoms vary depending on the cultivar from mild to severe which may have a significant impact in yield. The data obtained from studying SVNV diversity led to the following conclusions: The virus just recently moved to the United States or recently moved from an alternative host to soybean. Virus homogeneity indicates that symptom severity is primarily because of plant germplasm rather than diverse virus strains. Based on those hypotheses we have identified the virus vector and alternative hosts in the field that may assist in the overwintering of the virus. We are evaluating germplasm for resistance to the virus so as to minimize yield losses. Given that the value of US soybean is measured in the billions of dollars this work could save growers tens of millions of dollars by minimizing disease impact. The rose industry, with an estimated value of $200 million, is affected by several diseases. Rose rosette disease is the most important issue for the industry as it makes plants unmarketable and has the potential to wipe out nursery material if left unattended, leading to losses that may result in the closure of businesses. We have identified the causal agent of the disease, Rose rosette virus and developed sensitive detection methods that enable for the rapid detection of the agent before the disease spreads and causes epidemics. We are currently working on approaches that will eliminate virus transmission even when the virus vector is present in the area

Publications

• Type: Journal Articles Status: Published Year Published: 2013 Citation: Thekke-Veetil, T., Aboughanem Sabanadzovic, N., Keller, K.E., Martin, R.R., Sabanadzovic S. and Tzanetakis, I.E. 2013. Molecular characterization and population structure of Blackberry vein banding associated virus, new ampelovirus associated with yellow vein disease. Virus Research 178: 234-240
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Poudel, B., Wintermantel, W.M., Cortez, A.A., Ho, T., Khadgi, A. and Tzanetakis, I.E. 2013. Epidemiology of Blackberry yellow vein associated virus. Plant Disease 97: 1352-1357
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Martin, R.R. and Tzanetakis, I.E. 2013. High risk strawberry viruses by region in the United States and Canada: Implications for certification, nurseries and fruit production. Plant Disease 97: 1358-1362
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Zhou, J. and Tzanetakis, I.E. 2013. Epidemiology of Soybean vein necrosis associated virus. Phytopathology 103: 966-971
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Tzanetakis I.E., Martin, R.R. and Wintermantel W.M. 2013. Epidemiology of criniviruses, an emerging problem in world agriculture. Frontiers in Microbiology 4:119
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Poudel, B., and Tzanetakis I.E. 2013. Population structure of blackberry chlorotic ringspot virus in the United States. Archives of Virology 158: 667-672
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Abou Ghanem-Sabanadzovic, N., Tzanetakis, I.E., and Sabanadzovic, S. 2013. Rubus canadensis virus 1, a novel betaflexivirus identified in blackberry. Archives of Virology 158:445449
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Martin, R.R., MacFarlane, S., Sabanadzovic, S., Quito-Avila, D.F., Poudel, B., and Tzanetakis, I.E. 2013. Viruses and virus diseases of Rubus. Plant Disease 97:168-182.
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Tzanetakis I.E. and Martin R.R. 2013. The expanding field of strawberry viruses and which are important in North America. International Journal of Fruit Science 13:184195
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Martin, R.R., Eastwell, K.C, Scott, S.W. and Tzanetakis I.E. 2013. Clean plants, the national clean plant network and harmonizing certification standards in the United States. Petria 22: 412.
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Thekke-Veetil, T., Sabanadzovic, S., Keller, K.E., Martin, R.R. and Tzanetakis, I.E. 2013. Genome organization and sequence diversity of a novel in blackberry ampelovirus. Petria 22: 371-375
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Ho, T. and Tzanetakis I.E. 2013. Sensitive detection of three berry fruit viruses by TaqMan� qPCR. Petria 22: 362-370.
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Sabanadzovic,S., Abou Ghanem-Sabanadzovic, N. and Tzanetakis I.E. 2013. A new flexivirus identified in blackberry. Petria 22: 356.
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Hassan, M. Keller, K.E., Martin, R.R. Sabanadzovic, S. and Tzanetakis, I.E. 2013. A new emaravirus detected in blackberries affected by yellow vein disease. Petria 22: 357-361
• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Poudel, B., Wintermantel, W.M., Sabanadzovic, S. and Tzanetakis I.E. 2013. Dissecting the epidemiology of Blackberry yellow vein associated virus and Blackberry chlorotic ringspot virus; a study on population structure, transmission and alternative hosts. Petria 22: 334-331.

Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: Epidemiology of negative sense RNA viruses in the genera Tospovirus and Emaravirus: Unlike positive strand RNA viruses, where development of infectious clones is feasible, plant negative sense RNA viruses present a challenge and there are no infectious clones developed to date, partially because of the toxicity associated with protein expression in-planta. Notwithstanding, we have fulfilled Koch's postulates for a tospovirus and two emaraviruses proving evidence beyond doubt that they are the causal agents of their respective diseases. In the case of vein necrosis, the most widespread soybean disease in the United States, the soybean thrip was identified as an efficient vector of the virus; providing for the first time evidence that a species in the subfamily Sericothripinae is able to transmit a plant virus. More than seventy years after the first report, we were able to fulfill Koch's postulates for Rose rosette disease demonstrating that Rose rosette virus is the causal agent of the disease and replicates efficiently in its vector Phylocoptes fructiphilius. Blackberry leaf mottle associated virus is a newly identified emaravirus, discovered by the Tzanetakis lab. The dryberry mite, P. gracilis was identified as a virus vector. This is of major concern as this mite is often found in blackberry fields. If this mite species follows the pattern of other eriophyid mites vectoring viruses, found in at least 15-fold higher populations in infected material compared to healthy plants, then Blackberry leaf mottle associated virus can emerge as a major problem for blackberry production in the southcentral and southeastern United States. Blueberry mosaic has been a disease of unknown etiology and we have now completed the genome of the putative causal agent. We collaborated with scientists in the United States and Europe to determine the soil-borne vector, study the population structure of the virus and evaluate the reaction of all major highbush and rabbiteye cultivars and hybrids to the virus and disease. In blackberry, the yellow vein disease study continues and an additional three viruses have been identified in affected plants. The incidence of major viruses in the complexes has been studied in detail and using a forencics approach we determined that there are native virus populations transmitted to young plants in the field in the southern United States. The results of this CRIS project have been communicated to the stakeholders (growers, nurserymen, research and extention personnel) through several presentations in local, regional national and international meetings. Also, the PI has written several non technical articles and prepared extention publications that can be easily accessed by all interested parties. PARTICIPANTS: Robert R. Martin, Jana Lee and Inga Zasada, USDA-ARS in Corvallis, OR; William Wintermantel, USDA-ARS in Salinas, CA; Sead Sabanadzovic and Thomas Allen, Mississippi State University; Simon Scott, Clemson University; Gina Fernandez and Hannah Burrack, NC State University; Les Domier; USDA-ARS-Urbana, IL, Pengyin Chen, U of Arkansas, Fayetteville; Georgios Vidalakis; UC Riverside. TARGET AUDIENCES: Growers, Industry (nurseries- propagators), researchers working on small fruit; soybean and ornamentals PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Soybean vein necrosis disease has been found in all major soybean production areas of the United States and is closely associated to a new virus named Soybean vein necrosis virus (SVNV). Disease distribution and virus population structure was examined. Data were used to develop detection protocols that have the capacity to detect all virus isolates. Several species were found to sustain virus replication and Koch's postulates were fulfilled using soybean thrips. The identification of the causal agent of the disease and its vectors in combination with the discovery of morning glory as an alternative host of the virus has major implications in the management of soybean vein necrosis. Given the widespread incidence of the disease, information on the epidemiology of the causal agent provides much needed information for better management in the field. Blackberry yellow vein disease (BYVD) continues to be a major bottleneck for blackberry production in the southcentral and southeastern United States. The disease reduces yield and makes farming unprofitable. Using various templates and next generation sequencing platforms, several new viruses associated with the disease have been identified in the last few years. In 2012, three new viruses were discovered and studied in detail, including genomics and epidemiology. The most important factor for disease control is the identification of the causal agents and their epidemiology. The research performed last year provided additional information on the identity of the virus complexes that cause the most important disease of blackberry in the Eastern United States. These discoveries also assist the nursery industry as there are now tests able to detect the viruses and minimize their movement in areas that are absent. Blueberry mosaic disease (BMD) has been described more than 60 years ago and is found in major production areas in North America. Notwithstanding, no pathogen was found associated with the disease. The putative causal agent of BMD, a new virus, has been identified and studied in detail. The genome of the virus has been determined and the population structure of the virus, in both the United States and Europe, was studied. Detection tests are now available and have been successfully employed to detect the virus in all plants with typical disease symptoms. Genomics and bioinformatics have been applied to identify the virus vector. With the development of detection protocols it is now feasible to test and evaluate disease losses. It is also possible to test for asymptomatic infections that may serve as reservoir for the virus. This is particularly important for the nursery industry as it will minimize virus movement in BMD-free areas.

Publications

• Peer-reviewed journals (2012)-
• 1. Martin, R.R., Polashock, J.J., and Tzanetakis, I.E. (2012). New and emerging viruses of blueberry and cranberry. Viruses 4: 2831-2852
• 2. Laney, A. G., Hassan, M. and Tzanetakis, I. E.(2012). An integrated badnavirus is prevalent in fig germplasm. Phytopathology 102: 1182-1189.
• 4. Laney, A.G., Avanzato M.V. and Tzanetakis I.E. (2012). High incidence of seed transmission of Papaya ringspot virus and Watermelon mosaic virus, two viruses newly identified in Robinia pseudoacacia. European Journal of Plant Pathology 134:227-230
• 5. Gratsia, Μ.Ε., Kyriakopoulou, P.E., Voloudakis, A.E., Fasseas, C. and Tzanetakis, Ι.Ε. (2012). First Report of Olive mild mosaic virus and Sowbane mosaic virus in Spinach in Greece. Plant Disease 96: 1230.
• 6. Tzanetakis I.E. (2012). The Gordian knot of small fruit virology: Emerging diseases and their control. APSnet Features Jan. (2012), doi:10.1094/APSnetFeature-(2012)-0112
• Popular articles (2012):
• 3. Poudel, B., Sabanadzovic, S., Bujarski, J. and Tzanetakis I.E. (2012). Population structure of Blackberry yellow vein associated virus, an emerging crinivirus. Virus Research 169: 272-275
• 1. Tzanetakis I.E. (2012) The importance of virus-tested material and the National Clean Plant Network. The Bramble (North American Raspberry & Blackberry Association Newsletter), June (2012)
• 2. Poudel B. and Tzanetakis I.E. (2012). Variability and host range of blackberry chlorotic ring spot virus. The Bramble, June (2012)
• 3. Tzanetakis I.E. (2012)The importance of virus-tested strawberries and the National Clean Plant Network. The Strawberry Grower (North Carolina Strawberry Association), April (2012)
• 4. Tzanetakis, I.E. and Rupe, J. (2012).Researchers identifying cause of soybean green bean syndrome. Delta Farm Press, February (2012)
• Meeting proceedings (2012)- Gergerich, R.C., Eastwell, K.C., Golino, D.A., Martin, R.R., Vidalakis, G. Welliver, R.A. and Tzanetakis I.E. (2012). Harmonization of Certification Standards for National Clean Plant Network Commodities. International Council for the Study of Virus and Virus-like Diseases of the Grapevine abstract book 274.
• Zhou, J. and Tzanetakis I.E. (2012). Epidemiology of Soybean vein necrosis associated virus. Phytopathology 102: S4.144.
• Thekke-Veetil, T., Sabanadzovic, S., Keller, K.E., Martin, R.R. and Tzanetakis, I.E. (2012). Genetic variation of a novel ampelovirus in blackberry. Phytopathology 102: S4.119.
• Ho, T. and Tzanetakis I.E. (2012). TaqMan qPCR detection of three berry fruit ilarviruses. Phytopathology 102: S4.53.
• Tzanetakis I.E., Finn C.E., Clark, J.R. et al. (2012). Epidemiology and control of blackberry yellow vein disease. American Society for Horticultural Science national meeting 10149.
• Quito-Avila, D., Lightle, D., Tzanetakis, I.E. et al. (2012). Three viruses contribute to the raspberry crumbly fruit phenotype. American Society for Horticultural Science national meeting 10458.
• Quito-Avila, D., Tzanetakis, I.E., and Martin, R.R. (2012). Crumbly fruit symptoms in Meeker red raspberry are more severe with mixed virus infections. American Society for Horticultural Science national meeting 10210.
• Poudel, B., Wintermantel, W.M., Sabanadzovic, S. and Tzanetakis I.E. (2012). Epidemiology of blackberry yellow vein associated virus and blackberry chlorotic ringspot virus, two major components of blackberry yellow vein disease. American Society for Horticultural Science national meeting 10453.
• Poudel, B., Wintermantel, W.M., Sabanadzovic, S. and Tzanetakis I.E. (2012). Dissecting the epidemiology of Blackberry yellow vein associated virus and Blackberry chlorotic ringspot virus: a study on population structure, transmission and alternative hosts. International conference on virus and other graft transmissible diseases of fruit crops abstract book 66.
• Martin, R.R., Eastwell, K.C, Scott, S.W. and Tzanetakis I.E. (2012). Clean plants, the national clean plant network and harmonizing certification standards in the United States. International conference on virus and other graft transmissible diseases of fruit crops abstract book 81.
• Sabanadzovic,S., Abou Ghanem-Sabanadzovic, N. and Tzanetakis I.E. (2012). A new flexivirus identified in blackberry. International conference on virus and other graft transmissible diseases of fruit crops abstract book 188.
• Hassan., M., Keller, K.E., Martin, R.R. Sabanadzovic, S. and Tzanetakis, I.E. (2012). A new emaravirus detected in blackberries affected by yellow vein disease. International conference on virus and other graft transmissible diseases of fruit crops abstract book 189.
• Ho, T. and Tzanetakis I.E. (2012). Sensitive detection of three berry fruit viruses by TaqMan qPCR. International conference on virus and other graft transmissible diseases of fruit crops abstract book 190.
• Thekke-Veetil, T., Sabanadzovic, S., Keller, K.E., Martin, R.R. and Tzanetakis, I.E. (2012). Genome organization and sequence diversity of a novel in blackberry ampelovirus. International conference on virus and other graft transmissible diseases of fruit crops, abstract book 191.
• Tzanetakis I.E. (2012).The expanding world of small fruit viruses. Special Topic Symposium: Virus ecology and epidemiology, SWARM Division of AAAS abstract book 134.
• Zhou, J., Keller, K.E., Martin R.R. and Tzanetakis I.E. (2012). An emerging problem for Celtis spp. - a novel ampelovirus associated with mottling symptoms. Phytopathology 102: S 2.11.
• Laney, A.G., Kitajima, E. W. and Tzanetakis I.E. (2012). Are emaraviruses mite viruses The Rose rosette paradigm. Phytopathology 102: S 2.7.
• Tzanetakis I.E. and Martin R.R. (2012). Incidence of major strawberry viruses in North America. (2012) International Strawberry Symposium abstract book 174

Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: Activities: After a period of over 40 years we identified a virus associated with blueberry mosaic disease. The new virus has been detected in all symptomatic plants collected from AR, MI, NJ and OR. A new widespread, integrated virus in Ficus carica was characterized. The virus has been found in the vast majority of the samples obtained from seven states, whereas it has also been found in the Mediterranean region. The ability of the virus to integrate in the host genome is of concern but detection procedures have been developed that can differentiate between the episomal and integrated forms of the virus. The work on blackberry yellow vein disease yielded an additional three virus species whereas epidemiological studies on Blackberry yellow vein associated virus (BYVaV) and Blackberry chlorotic ringspot virus (BCRV) proved transmission of BYVaV by two whitefly species and high seed transmission of BCRV in several hosts. Apple was verified as a new host of BCRV. The PI also coordinates the effort for the development of a national, harmonized certification program for blueberries. Three graduate students and four postdoctoral associates have been involved in those projects with their work being published or under review at this point in time. The PI taught Seminar and prepared a short course on bioinformatics whereas and contributed in another course offered by the Department of Plant Pathology at the University of Arkansas (Principles of Plant Pathology). Events: Participated and presented at the annual American Phytopathological Society meeting in Honolulu, HI; the Georgia Fruit and Vegetable Growers Association annual meeting in Savannah, GA; the North American Strawberry Growers Symposium in Tampa, FL and the WERA20 and NCCC-212 annual meetings in Portland, OR and Fayetteville, AR. He also participated and presented at the 10th Rubus-Ribes Symposium held in Zladibor, Serbia. Participated and presented in the annual meeting of the Clean Plant Network in Washington DC, where he gave a keynote address on next generation detection methods. Services: The PI is member of the editorial board of three peer-review journals helping in the critical review of articles in his sphere of expertise. He also provided service to the blackberry and soybean growers on the detection of viruses in the respective crops Products: Several peer-reviewed and technical articles, book chapters and proceedings were published in 2011. The PI laboratory developed several new detection protocols for small fruit viruses, based on information of several isolates sequenced in his lab. Those protocols are readily available to all interesting parties as they have been verified on several virus isolates. Dissemination: Meetings with blackberry and blueberry growers in Georgia and strawberry growers in Florida explained the problems caused by virus diseases in the crops and laid out measures to minimize movement of the pathogens. In the annual Clean Plant Network meeting the importance of next generation detection methods was outlined to the stakeholders (growers, nurserymen, and researchers). PARTICIPANTS: Collaborators Robert R. Martin, Jana Lee and Inga Zasada, USDA-ARS in Corvallis, OR; William Wintermantel, USDA-ARS in Salinas, CA; Sead Sabanadzovic, Mississippi State University; Simon Scott, Clemson University; Gina Fernandez and Hannah Burrack, NC State University; Stella Kantartzi, Southern Illinois University; Georgios Vidalakis; UC Riverside. Students Bindu Poudel Jing Zhou Alma G. Laney Postdoctoral associates Dr. Thanuja Thekke Veetil Dr. Thien Ho Dr.Marites Sales Dr. Mohammed Hassan Other professionals Dr. Rose Gergerich TARGET AUDIENCES: Growers, Industry (nurseries- propagators), researchers working on small fruit; soybean and ornamentals. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
The work on blackberry virus epidemiology has helped to better understand virus movement in the field and the development of the appropriate preventative measures to avoid virus spread. For example the identification of the whitefly vectors for BYVaV combined with the field data on their movement provides the essentials for the development of best management practices where insecticide sprays will only be used at the time of vector movement in blackberry fields. The new integrated badnavirus in Ficus carica is the first such virus identified in the host. Fig is clonally propagated and detection of the new virus before propagation is essential to minimize disease incidence as it is well documented that badnaviruses can cause significant losses and play an important role in disease development when found in complexes with other viruses. The new detection protocols developed in the Tzanetakis lab will improve phytosanitation of small fruit crops two-fold: The new tests are much more sensitive (in many cases more than 1000-times) than conventional RT-PC protocols whereas they are developed after sequencing several isolates collected from distant areas providing assurance that they can detect a wide array of isolates. As part of the National Clean Plant Network the PI collaborates with several Centers to improve and develop new detection protocols and methods. The participation in NCPN and his presentations in regional and national meetings have helped in the education of the stakeholders on the importance of clean plant material for the longevity and the long term profitability of the small fruit plantings. It is also important to note that the PI is leading the effort for the harmonization of all regulations involved in blueberry propagation. Meetings with stakeholders and regulators from all major blueberry propagation states have been successful and we are now in the process of developing pilot programs to implement the new regulations. This will not only help easier and hassle propagation material movement between states but will also help maintain the leadership position of the U.S. blueberry nursery industry in a competitive global environment.

Publications

• Peer-Reviewed Journals 2011 Tzanetakis, I.E., Wintermantel, W.M., Poudel, B. and Zhou, J. 2011. Diodia vein chlorosis virus is a group-1 crinivirus. Archives of Virology 156: 2033-2037.
• Sabanadzovic, S., Abou Ghanem-Sabanadzovic, N. and Tzanetakis, I.E. 2011. Blackberry virus E: an unusual flexivirus. Archives of Virology 156:1665-1669.
• Zhou, J., Kantartzi, S.K., Wen, R.-H., Newman, M., Hajimorad, M.R., Rupe, J.C. and Tzanetakis, I.E. 2011. Molecular characterization of a new tospovirus infecting soybean. Virus Genes 43: 289-295.
• Laney, A.G., Keller, K.E., Martin, R.R. and Tzanetakis I.E. 2011. A discovery 70 years in the making: Characterization of the Rose rosette virus. Journal of General Virology 92: 1727-1732.
• Quito-Avila, D.F., Jelkmann, W., Tzanetakis, I.E., Keller, K. and Martin, R.R. 2011. Complete sequence and genetic characterization of Raspberry latent virus, a novel member of the family Reoviridae. Virus Research 155: 397-405.
• Book Chapters 2011
• Martin, R.R., Zhou, J. and Tzanetakis, I.E. 2011. Blueberry latent virus: An amalgam of the Partitiviridae and the Totiviridae. Virus Research 155: 175-180.
• Tzanetakis, I.E. and Antoniw, J. 2011. Alphacryptovirus. The Springer Index of Viruses, 2nd Edition. Pp. 1169-1173.
• Martin, R.R., Jelkmann W. and Tzanetakis, I.E. 2011. Double-Stranded RNAs and their Use for characterization of Recalcitrant Viruses. Pp. 323-326, In: Virus and Virus-Like Diseases of Pome and Stone Fruits (Hadidi, A., Barba, M., Candresse, T. and Jelkmann, W., Eds.), APS Press, St. Paul, MN, USA.
• Proceedings 2011
• Tzanetakis, I.E. 2011. Novel closteroviruses in small fruit crops. Phytopathology 101:S229
• Poudel, B., Laney, A.G. and Tzanetakis I.E. 2011. Epidemiological studies on Blackberry chlorotic ringspot virus. Phytopathology 101:S145
• Laney, A.G., Hassan, M. and Tzanetakis, I.E. 2011 Characterization and epidemiological aspects of a novel badnavirus infecting fig. Phytopathology 101:S97
• Hassan, M. Keller, K.E., Martin R.R., Sabanadzovic S. and Tzanetakis, I.E. 2011. Characterization of a novel Emaravirus infecting blackberry. Phytopathology 101:S70
• Sabanadzovic, S. Keller, K, Martin, R.R. and Tzanetakis. I.E. 2011. Identification and characterization of a new ampelovirus infecting cultivated and wild blackberries. Phytopathology 101:S158
• Zhou, J., Keller, K.E., Martin R.R. and Tzanetakis, I.E. 2011. Sweet burden of sugarberry a novel ampelovirus found in Celtis laevigata.Phytopathology 101:S206
• Kanrar, S., Afunin, M., Greer, G. Tzanetakis, I.E. and Vidalakis, G. 2011. Viruses associated with yellow vein and vein enation disease of citrus. Phytopathology 101:S87
• Poudel, B. and Tzanetakis, I. E. 2011. Epidemiological studies on Blackberry yellow vein associated virus. Phytopathology 101:S206.
• Zhou, J. and Tzanetakis, I. E. 2011. A new virus disease in the U.S.: Soybean vein necrosis. Phytopathology 101:S206
• Tzanetakis I.E., S. Sabanadzovic, D.T. Johnson, H.J. Burrack, R. R. Martin, 2011. The emerging problem of blackberry yellow vein disease. X International Rubus and Ribes Symposium, pp.65.
• Poudel B., W.M. Wintermantel, S. Sabanadzovic, I.E. Tzanetakis, 2011 Epidemiological studies on Blackberry yellow vein associated virus and Blackberry chlorotic ringspot virus. X International Rubus and Ribes Symposium, pp.75.
• Sabanadzovic S., N. Abou Ghanem-Sabanadzovic, I.E. Tzanetakis, 2011. Two new filamentous viruses of blackberries. X International Rubus and Ribes Symposium,pp. 76.
• Technical 2011
• Poudel B. and Tzanetakis I.E. 2011. Studies on the diversity of Blackberry yellow vein associated virus. The Bramble 26-2: 13.
• Tzanetakis, I.E., Quito, D. and Martin R.R. 2011. Two new virus diseases in Rubus: Blackberry yellow vein and raspberry crumbly fruit. Small Fruit News 11-1:4-7.

Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: Activities: In the last year we have made significant progress in the understanding of major diseases of ornamental crops including rose and redbud, with the two new viruses identified associated with rose rosette and redbud yellow ringspot disease found in 100% of infected material collected from several states. We have determined that Soybean vein necrosis virus is very widespread and is found in 100% of all samples showing typical soybean vein necrosis disease symptoms. We discovered that a new virus in blueberry, the type member of a new virus taxon, is the most widespread virus in the crop with more than 50% of all plants tested being positive for it. It is important to note that this is an asymptomatic virus but its role in mixed infections is to be determined. Three graduate students and a postdoctoral associate have been involved in those projects with their work being published or under review at this point in time. This has been the second year of teaching for the PI. He tought the Plant Virology course, prepared short courses on DNA plant viruses, bioinfoirmatics and deep sequencing technologies and contributed in two other courses offered by the Department of Plant Pathology at the University of Arkansas (Principles of Plant Pathology and Seminar). Events: Participated and presented at the annual American Phytopathological Society meeting in Charlotte, NC; the Georgia Fruit and Vegetable Growers Association annual meeting in Savannah, GA; the annual Arkansas/Oklahoma Horticulture Industries Show, in Tulsa, Oklahoma; the WERA20 and NCERA-200 annual meetings in Boise, ID and Ames, IA, respectively; and a workshop on blueberry diseases for Arkansas growers held in Clarksville, AR. Participated also in annual national meeting of the Clean Plant Network in Davis, CA. Services: Growers in NC, SC and GA were educated for ways to minimize blackberry virus movement in-between and within fields. The PI of the project is member of the editorial board of three peer-review journals helping in the critical review of articles in his sphere of expertise. Products: Collaborations were established with Mississippi State University, North Carolina State University, USDA-ARS in Corvallis OR and Salinas, CA and within the University of Arkansas on tackling the problems associated with Blackberry yellow vein disease. Collaborations within University of Arkansas and Mississippi State University were formed to study Soybean green bean syndrome. Collaborations with University of Tennessee to study the epidemiology of Soybean vein necrosis virus. Collaborations formed with USDA-ARS on blueberry viruses. Dissemination: Meetings with blackberry and blueberry growers in Georgia and Oklahoma explained the problems caused by virus diseases in the crops and laid out measures to minimize movement of the pathogens. In the annual meeting of the Clean Plant Network the importance of berry viruses were outlined to the stakeholders (growers, nurserymen, and researchers) and the appropriate measures were outlined for appropriate dissemination of berry plant material. PARTICIPANTS: Robert R. Martin, Jana Lee and Inga Zasada, USDA-ARS in Corvallis, OR; William Wintermantel, USDA-ARS in Salinas, CA; Sead Sabanadzovic, Mississippi State University; Simon Scott, Clemson University; Gina Fernandez and Hannah Burrack, NC State University; Reza Hajimorad, University of Tennessee; Stella Kantartzi, Southern Illinois University; Georgios Vidalakis; UC Riverside. TARGET AUDIENCES: Growers, Industry (nurseries- propagators), researchers working on small fruit; soybean and ornamentals PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Outcomes/impacts: The work on blackberry yellow vein disease (BYVD) has led to the discovery of an additional three viruses associated with the disease helping us understand the importance of virus complexes in the onset of the disease. We continue to develop sensitive and reliable tests for all viruses found in Rubus that are being used by researchers and the industry (nurseries) to eliminate the viruses from the mother plants. This new technology is being used to test new Rubus accessions before they are released as named cultivars and the first such cultivar was released in 2010 as PrimeArk 45. This have great benefits to the growers given that clean propagation material does not only yield better but also the life expectancy of the orchards is extended. Surveys performed in several states on Rose rosette, Redbud yellow ringspot and Soybean vein necrosis virus have been very informative as viruses have been found in all symptomatic plants of the respective diseases leading to a better understanding of the disease. The Tzanetakis lab is named a Center for Excellence in Small Fruit Virology by the National Clean Plant Network. The participation in NCPN and his presentations in regional and national meetings have helped in the education of the stakeholders on the importance of clean plant material for the longevity and the long term profitability of the small fruit plantings

Publications

• JOURNAL ARTICLES:1.Kraus, J., Cleveland, S., Putnam, M.L., Keller, K.E., Martin, R.R. and Tzanetakis, I.E. 2010. A new potyvirus infects verbena exhibiting leaf mottling symptoms. Plant Disease 94:1132-1136. 2. Poudel, B., Laney, A.G. and Tzanetakis I.E. 2010. First report of Cucumber mosaic virus infecting Blephilia hirsuta in North America. Plant Disease 94:1070. 3. Tzanetakis, I.E., Martin, R.R. and Scott, S.W. 2010. Genomic sequences of blackberry chlorotic ringspot virus and strawberry necrotic shock virus and the phylogeny of viruses in subgroup 1 of the genus Ilarvirus. Archives of Virology 155:557-561. 4. Tzanetakis, I.E., Postman, J.D., Samad, A. and Martin, R.R. 2010. Mint Viruses: Beauty, Stealth and Disease. Plant Disease 94:4-12. PAPERS IN PROCEEDINGS: 1.Tzanetakis, I.E. 2010. Emerging strawberry virus and virus-like diseases in the world. Julius-Kuhn-Archiv 427:41-43. Tzanetakis, I.E., Laney, A.G., Keller, K.E., and Martin, R.R. 2010. New viruses found in fig exhibiting mosaic symptoms. Julius-Kuhn-Archiv 427:79-82. NEWSLETTERS Tzanetakis, I.E. Survey for the Presence of 10 New Viruses in Blackberry. The Bramble (North American Raspberry & Blackberry Association Newsletter), March 2010. ABSTRACTS:1.Tzanetakis, I. E., Cortez, A., Zhou, J., Poudel, B., Larsen, R.C. and Wintermantel, W.M. Epidemiology of two Diodia virginiana criniviruses. 2010 APS (American Phytopathological Society) annual meeting. 2.Sabanadzovic, S. and Tzanetakis, I.E. A new ilarvirus from subgroup 1 infects ligustrum. 2010 APS annual meeting. 3.Poudel, B., Wintermantel, W. M., Sabanadzovic, S. and Tzanetakis, I.E. Epidemiological studies on Blackberry yellow vein associated virus. 2010 APS annual meeting.4.Laney, A., Gergerich, R., Keller, K, Martin, R.R. and Tzanetakis. I.E. Rose rosette and Redbud yellow ringspot agents are caused by two new emaraviruses. 2010 APS meeting. 5.Laney, A., Gergerich, R.C. and Tzanetakis, I.E. Redbud yellow ringspot disease: Thirty years of research. 2010 APS Southern region meeting.

Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Activities: There have been steps towards the characterization of the agents involved in several soybean, Rubus, Vaccinium and ornamental plant disease. Experiments have been performed to determine the etiology of Soybean vein necrosis, Soybean green bean syndrome, Blackberry yellow vein, rose rosette, redbud yellow ringspot and blueberry mosaic diseases. Three graduate students have been involved in those projects with their work being prepared for publication. This has been the first year of teaching for the PI. He has developed lectures and laboratory exercises for Plant Virology course, prepared a short course on immunological detection of plant viruses and contributed in two other courses offered by the Department of Plant Pathology at the University of Arkansas. Events: Participated and presented at the annual American Phytopathological Society meeting in Portland, OR; the 21st International Conference on Virus and other Graft Transmissible Diseases of Fruit Crops in Neustadt/Weinstrasse, Germany; the Georgia Fruit and Vegetable Growers Association annual meeting in Savannah, GA; the WERA20 and NCR-200 annual meetings in Kalamazoo, MI and Ames, IA, respectively; and a workshop on blueberry diseases for Arkansas growers held in Clarksville, AR. Participated also in the first (forming) meeting of the Clean Plant Network for berries in St. Louis, MO. Services: Worked with blackberry breeder at the University of Arkansas to test his material for all known Rubus viruses before release of the named variety to the public. Growers in NC, SC, GA and OK were educated for ways to minimize blackberry virus movement in-between and within fields. Foreign agency (MAF Biosecurity New Zealand) was consulted on the quarantine list of Rubus and Vaccinium viruses for the country. Products: Collaborations were established with Mississippi State University, North Carolina State University, USDA-ARS in Corvallis OR and Salinas, CA and within the University of Arkansas on tackling the problems associated with Blackberry yellow vein disease. Collaborations within University of Arkansas and Mississippi State University were formed to study Soybean green bean syndrome. Collaborations with University of Tennessee to study the epidemiology of Soybean vein necrosis virus. Collaborations formed with USDA-ARS on blueberry viruses. Techniques developed for detections of blackberry viruses were disseminated to North Carolina State University and MAF Biosecurity New Zealand. New techniques were developed for rose rosette and redbud yellow ringspot viruses, two new (yet unnamed) viruses in hackberry, three new (yet unnamed) viruses in blackberry and soybean vein necrosis virus. Dissemination: Meetings with blackberry and blueberry growers in Georgia and Arkansas explained the problems caused by virus diseases in the crops and laid out measures to minimize movement of the pathogens. In the forming meeting of the Clean Plant Network for berries the importance of berry viruses were outlined to the stakeholders (growers, nurserymen, and researchers) and the appropriate measures were outlined for appropriate dissemination of berry plant material. PARTICIPANTS: Robert R. Martin, Jana Lee and Inga Zasada, USDA-ARS in Corvallis, OR; William Wintermantel, USDA-ARS in Salinas, CA; Sead Sabanadzovic, Mississippi State University; Simon Scott, Clemson University; Gina Fernandez and Hannah Burrack, NC State University; Reza Hajimorad, University of Tennessee; Stella Kantartzi, Southern Illinois University; Georgios Vidalakis; UC Riverside. TARGET AUDIENCES: Growers, Industry (nurseries- propagators), researchers working on small fruit; soybean and ornamentals. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
The work on blackberry yellow vein disease (BYVD) has shed light in one of the most complex diseases of small fruit crops. We have determined that BYVD is caused by a combination of viruses the identity of which changes depending on the geographic region. That is, different viruses can cause identical symptoms in affected plants and the number rather than the virus identity is more important for the onset of symptoms. In the last few years the PI and his collaborators have double the number of the viruses infecting Rubus (PI has worked on 90% of the new agents) and have developed sensitive and reliable tests for all those viruses that can be used by researchers and the industry (nurseries) to eliminate the viruses from the mother plants. This new knowledge and the detection methods have been used to test new Rubus accessions before they are released as named cultivars. The PI is collaborating with breeders in Arkansas and North Carolina ensuring that the material is free of all known viruses. This have great benefits to the growers given that clean propagation material does not only yield better but also the life expectancy of the orchards is extended. Rose rosette has been described almost 70 years ago and no causal agent had been described until this year. A graduate student discovered the causal agent and has developed a detection method for the virus that can be used for early detection of the disease. This is of particular importance to the ornamental industry given that there is a latent period of about a year before symptoms develop, time where vectors can disseminate the virus and cause widespread epidemics. In soybean, we (University of Arkansas and Tennessee) have identified a virus associated with vein necrosis, a disorder that has been observed for about a decade in the southern states and no pathogenic agents was isolated. We have discovered a tospovirus and developed detection methods for the virus. The virus has been detected in 100% of symptomatic material in major production areas in AR, IL, TN and KY and we are working towards the identification of a vector that based on the mode of transmission of tospoviruses is probably a thrips.

Publications

• Tzanetakis, I.E., Tsai, C.-H., Martin, R.R. and Dreher, T.W. 2009. A tymovirus with an atypical 3 -UTR illuminates the possibilities for 3 -UTR evolution. Virology, 392:238-245. Wintermantel, W.M., Ladky L.L., Gulati-Sakhuja, A., Li, R. and Tzanetakis, I.E. 2009. The complete nucleotide sequence and genome organization of Tomato infectious chlorosis virus: A distinct crinivirus most closely related to Lettuce infectious yellows virus. Archives of Virology 154:1335-1341. Salem, N.M., Chen, A.Y., Tzanetakis, I.E., Mongkolsiriwattana, C. and Ng, J.C. 2009. Further complexity of the genus Crinivirus revealed by the complete genome sequence of Lettuce chlorosis virus (LCV) and the similar temporal accumulation of LCV genomic RNAs 1 and 2. Virology 390:45-55. Tzanetakis, I.E., Guzman-Baeny, T.L., VanEsbroeck, Z.P., Fernandez G.E. and Μartin, R.R. 2009. First report of Impatiens necrotic spot virus in blackberry Southeastern United States. Plant Disease 93:432. Tzanetakis I.E. 2009. First report of Cucumber mosaic virus in Anemone sp. in the United States. Plant Disease 93:431. Shin, H-I., Tzanetakis I.E., Dreher, T.W. and Cho T-J. 2009. The 5 -UTR of Turnip yellow mosaic virus does not include a critical encapsidation signal. Virology 387:427-35. Sabanadzovic, S., Valverde, R.A., Brown, J.K., Martin, R.R. Tzanetakis, IE. 2009. Southern tomato virus: The link between the families Totiviridae and Partitiviridae. Virus Research 140:130-137. Ragab, M., El-Dougdoug, K., Mousa, S., Attia, A., Sobolev, I., Spiegel, S., Freeman, S., Zeidan, M., Tzanetakis, I.E., Martin, R.R. 2009. Detection of Strawberry Viruses in Egypt. Acta Horticulturae 842:319-322. Martin, R.R., Tzanetakis, I.E., Caruso, F.L. and Polashock, J.J. 2009. Emerging and Reemerging Virus Diseases of Blueberry and Cranberry. Acta Horticulturae 810:299-304. Tzanetakis,I. E., Wen,R., Newman,M., Hajimorad, R., 2009.Soybean vein necrosis virus: A new threat to soybean production in Southeastern United States Phytopathology 99:S131 Sabanadzovic, S.,Abou Ghanem-Sabanadzovic, N., Tzanetakis, I. E., 2009. Nucleotide sequences and detection of a new flexivirus from blackberry. Phytopathology 99:S112 Tzanetakis, I. E., Chowdhury,M. R., Laney, A. G., Martin, R. R. 2009. New viruses found in fig exhibiting mosaic symptoms. Phytopathology 99:S131 Wintermantel, W. M., Hladky, L. L., Gulati-Sakhuja, A., Li, R., Liu, H.,Tzanetakis, I. E. 2009.The complete nucleotide sequence and genome organization of Tomato infectious chlorosis virus: A distinct crinivirus most closely related to LIYV.Phytopathology 99:S142