@article{abad_parks_new_fuentes_jester_moyer_2007, title={First report of Sweet potato chlorotic stunt virus, a component of sweetpotato virus disease, in North Carolina.}, volume={91}, ISSN={["0191-2917"]}, DOI={10.1094/PDIS-91-3-0327B}, abstractNote={ Sweet potato chlorotic stunt virus (SPCSV) is the whitefly-transmitted component of the sweet potato virus disease (SPVD), a devastating disease originally described in Africa (4). Two isolates designated as G-01 and T-03 were obtained in North Carolina in July 2001 and October 2003, respectively, from plants of cv. Beauregard exhibiting symptoms typical of SPVD, including stunting, leaf narrowing and distortion, vein clearing, and chlorotic mosaic. Sap extract from symptomatic plants tested positive for SPCSV by nitrocellulose immuno-dot blot, using monoclonal antibodies specific for SPCSV obtained from the International Potato Center. Total RNA was extracted from 100 mg of symptomatic leaf tissue by using the PureLink Total RNA Purification System Kit from Invitrogen (Carlsbad, CA) with a minor modification (adding 2% PVP-40 and 1% 2-mercaptoethanol to the extraction buffer) (1). Results were confirmed by reverse transcription (RT)-PCR using primers CP1 and CP3 and HSP70-A/HSP70-B (2), corresponding to the capsid protein and ‘heat shock’ protein genes, respectively. HSP70 amplicons were cloned using the TOPO TA Cloning Kit (Invitrogen) and sequenced. At the nucleotide level, viral sequences from clones from both isolates were an average 99.4% similar to West Africa and 77.9% to East Africa sequences of SPCSV from Genbank (1). Although the isolates were collected from different fields, viral sequences generated from clones for T-03 and G-01 differed by only six nucleotides and were identical at the amino acid level. The neighbor-joining phylogenetic tree constructed using the HSP70 gene fragment (39 nt) delineated two major clusters with two subpopulations each: Cluster 1, “East Africa”, consisted of East Africa and Peru subpopulations; Cluster 2, “West Africa”, consisted of Argentina-Brazil and USA-West Africa subpopulations (1). In addition, SPCSV isolates from East Africa and West Africa clusters were sufficiently distant phylogenetically to suggest that they may correspond to two different criniviruses, with an average similarity between the populations of 78.14% and an average within the populations above 89%. Hudson's tests confirmed the presence of genetically distinct SPCSV groups with high statistical significance (1). Two groups (Peru and East Africa) were differentiated in the East Africa cluster, and three groups (Argentina-Brazil, USA, and West Africa) were differentiated in the West Africa cluster, suggesting that the USA population is not a recent introduction. Although SPCSV was previously reported in the United States, the source was a single accession of cv. White Bunch from the USDA Sweetpotato Germplasm Repository (3). Sweet potato feathery mottle virus (SPFMV) (family Potyviridae, genus Potyvirus), the other component of SPVD, was also detected in both cultivars. To our knowledge, this is the first report of SPCSV in sweetpotato fields in the United States.  References: (1) J. A. Abad et al. Phytopathology (Abstr.) 96(suppl.):S1, 2006. (2) T. Alicai et al. Plant Pathol. 48:718, 1999. (3) G. Pio-Ribeiro et al. Plant Dis. 80:551, 1996. (4) G. A. Schaefer and E. R. Terry. Phytopathology 66:642, 1977. }, number={3}, journal={PLANT DISEASE}, author={Abad, J. A. and Parks, E. J. and New, S. L. and Fuentes, S. and Jester, W. and Moyer, J. W.}, year={2007}, month={Mar}, pages={327–327} }
 @article{de breuil_abad_nome_giolitti_lambertini_lenardon_2007, title={Groundnut ringspot virus: an emerging Tospovirus inducing disease in peanut crops}, volume={155}, ISSN={["1439-0434"]}, DOI={10.1111/j.1439-0434.2007.01221.x}, abstractNote={AbstractPeanut (Arachis hypogaea L.) plants showing Tospovirus‐like symptoms were observed in Córdoba province (central Argentina). Peanut plants were collected and tested to identify the causal agent. Tospovirus‐like particles were observed by electron microscopy and Groundnut ringspot virus (GRSV) was identified by double antibody sandwich‐enzyme‐linked immunosorbent assay (DAS‐ELISA) and reverse transcription‐polymerase chain reaction (RT‐PCR). Partial nucleotide and deduced amino acid sequences of the nucleocapsid (N) gene indicated a high degree of identity with other GRSV sequences. This is the first report of the GRSV occurrence on peanuts in Argentina.}, number={4}, journal={JOURNAL OF PHYTOPATHOLOGY}, author={De Breuil, S. and Abad, J. A. and Nome, C. F. and Giolitti, F. J. and Lambertini, P. L. and Lenardon, S.}, year={2007}, month={Apr}, pages={251–254} }
 @article{myers_sutton_abad_kennedy_2007, title={Pierce's disease of grapevines: Identification of the primary vectors in North Carolina}, volume={97}, ISSN={["1943-7684"]}, DOI={10.1094/PHYTO-97-11-1440}, abstractNote={ In the past 10 years, the winegrape industry in the southeastern United States has experienced rapid growth; however, further expansion may be inhibited by Pierce's disease (PD). Epidemiological studies were conducted to identify the primary vectors of Xylella fastidiosa, the cause of PD of grape, by surveying sharpshooter population dynamics in the eastern Piedmont and Coastal Plain regions of North Carolina. Sharpshooter species were assessed for the presence of X. fastidiosa in the field. Leafhoppers were trapped in three vineyards in the eastern Piedmont and one vineyard in the northeastern Coastal Plain in 2004 and 2005. Four insects were identified as most abundant: Oncometopia orbona, Graphocephala versuta, Paraphlepsius irroratus, and Agalliota constricta. Adult specimens of O. orbona, G. versuta, and P. irroratus were tested for the presence of X. fastidiosa by nested polymerase chain reaction. In all, 27% of O. orbona, 28% of G. versuta, and 33% of P. irroratus trapped were positive for X. fastidiosa over the two seasons. Transmission experiments demonstrated that both O. orbona and G. versuta have the ability to transmit X. fastidiosa to grape. These vectors are likely to be important in all winegrowing regions of the Southeast, because their presence has been documented throughout the southern states. In DNA analyses, X. fastidiosa strains from insects trapped in North Carolina were genetically similar to one another and to the known “PD strain” from California. This is the first report of these two leafhopper species transmitting X. fastidiosa to grapevines in the Southeast. }, number={11}, journal={PHYTOPATHOLOGY}, author={Myers, Ashley L. and Sutton, Turner B. and Abad, Jorge A. and Kennedy, George G.}, year={2007}, month={Nov}, pages={1440–1450} }
 @article{abad_moyer_kennedy_holmes_cubeta_2005, title={Tomato spotted wilt virus on potato in eastern North Carolina}, volume={82}, ISSN={["1874-9380"]}, DOI={10.1007/BF02853592}, number={3}, journal={AMERICAN JOURNAL OF POTATO RESEARCH}, author={Abad, JA and Moyer, JW and Kennedy, GG and Holmes, GA and Cubeta, MA}, year={2005}, pages={255–261} }
 @article{tsompana_abad_purugganan_moyer_2005, title={The molecular population genetics of the Tomato spotted wilt virus (TSWV) genome}, volume={14}, ISSN={["1365-294X"]}, DOI={10.1111/j.1365-294X.2004.02392.x}, abstractNote={AbstractRNA viruses are characterized by high genetic variability resulting in rapid adaptation to new or resistant hosts. Research for plant RNA virus genetic structure and its variability has been relatively scarce compared to abundant research done for human and animal RNA viruses. Here, we utilized a molecular population genetic framework to characterize the evolution of a highly pathogenic plant RNA virus [Tomato spotted wilt virus (TSWV), Tospovirus, Bunyaviridae]. Data from genes encoding five viral proteins were used for phylogenetic analysis, and for estimation of population parameters, subpopulation differentiation, recombination, divergence between Tospovirus species, and selective constraints on the TSWV genome. Our analysis has defined the geographical structure of TSWV, attributed possibly to founder effects. Also, we identify positive selection favouring divergence between Tospovirus species. At the species level, purifying selection has acted to preserve protein function, although certain amino acids appear to be under positive selection. This analysis provides demonstration of population structuring and species‐wide population expansions in a multisegmented plant RNA virus, using sequence‐based molecular population genetic analyses. It also identifies specific amino acid sites subject to selection within Bunyaviridae and estimates the level of genetic heterogeneity of a highly pathogenic plant RNA virus. The study of the variability of TSWV populations lays the foundation in the development of strategies for the control of other viral diseases in floral crops.}, number={1}, journal={MOLECULAR ECOLOGY}, author={Tsompana, M and Abad, J and Purugganan, M and Moyer, JW}, year={2005}, month={Jan}, pages={53–66} }
 @article{lyerly_new_abad_moyer_2003, title={Identification of sweetpotato viruses using an RT- PCR based method}, volume={93}, journal={Phytopathology}, author={Lyerly, J. H. and New, S. L. and Abad, J. A. and Moyer, J. W.}, year={2003}, pages={S55} }
 @article{moyer_abad_new_bell_2002, title={Isolation, identification and detection of undescribed RNA sweetpotato viruses}, ISBN={["90-6605-985-0"]}, ISSN={["0567-7572"]}, DOI={10.17660/actahortic.2002.583.13}, number={583}, journal={PROCEEDINGS OF THE FIRST INTERNATIONAL CONFERENCE ON SWEETPOTATO: FOOD AND HEALTH FOR THE FUTURE}, author={Moyer, JW and Abad, JA and New, J and Bell, J}, year={2002}, pages={121–127} }
 @article{abad_conkling_moyer_1992, title={COMPARISON OF THE CAPSID PROTEIN CISTRON FROM SEROLOGICALLY DISTINCT STRAINS OF SWEET-POTATO FEATHERY MOTTLE VIRUS (SPFMV)}, volume={126}, ISSN={["1432-8798"]}, DOI={10.1007/BF01309691}, abstractNote={Complementary DNA clones corresponding to the 3' terminus of sweetpotato feathery mottle virus (SPFMV) strains RC and C were synthesized and sequenced. An open reading frame followed by a 3' terminal non-coding region of 222 nucleotides and a terminal polyadenylation track was present in clones from both strains. Putative N-terminal capsid protein cleavage sites were identified for both strains 945 nucleotides 5' of the first stop codon. Sequence comparisons of these strains show 98% nucleic acid identity in the last 351 nucleotides of the capsid protein cistron and 100% in the corresponding amino acids. This relatively short homologous sequence element near the C terminus is responsible for the wide spectrum hybridization among SPFMV strains using in vitro transcribed antiviral RNA probes (riboprobes). The sequence similarity in the remaining N terminal 645 nucleotides is only 62% and 65% for their predicted amino acids. A tendency of decreasing nucleotide mismatches in the alignment from 5' to 3' end of both capsid protein cistrons was detected. Although the alignment of the predicted amino acid sequence of the SPFMV-RC capsid protein with those of other potyviruses showed significant homology, hybridization with riboprobes from both the 5' and 3' regions of the capsid protein cistron of SPFMV was virus-specific.}, number={1-4}, journal={ARCHIVES OF VIROLOGY}, author={ABAD, JA and CONKLING, MA and MOYER, JW}, year={1992}, pages={147–157} }
 @article{abad_moyer_1992, title={DETECTION AND DISTRIBUTION OF SWEET-POTATO FEATHERY MOTTLE VIRUS IN SWEET-POTATO BY INVITRO-TRANSCRIBED RNA PROBES (RIBOPROBES), MEMBRANE IMMUNOBINDING ASSAY, AND DIRECT BLOTTING}, volume={82}, ISSN={["0031-949X"]}, DOI={10.1094/Phyto-82-300}, abstractNote={An in vitro-transcribed RNA probe (riboprobe) system was developed to detect sweetpotato feathery mottle virus (SPFMV) in infected plants. The essential components of the system include selection of an SPFMV cDNA clone that reacts with all known strains of SPFMV, optimization of assay procedures, and modified hybridization conditions. Additionally, a direct blotting technique on nitrocellulose membrane was developed to detect SPFMV by either riboprobe or membrane immunobinding assay (MIBA). The riboprobe system provided greater sensitivity of detection of virus in symptomless tissues than MIBA (...)}, number={3}, journal={PHYTOPATHOLOGY}, author={ABAD, JA and MOYER, JW}, year={1992}, month={Mar}, pages={300–305} }