Clinical experience and outcomes using a commercially available micro-plating system for metabone fractures in dogs and cats: 10 cases (2019-2023).

OBJECTIVES: To report the clinical experience and long-term outcome following metabone fracture stabilisation using a commercially available micro-plating system (VetKISS, 1.0-mm, IMEX Veterinary, USA). MATERIALS AND METHODS: Consecutive, client-owned cats and dogs weighing <7 kg, with traumatic metabone fractures stabilised using VetKISS micro-plates were prospectively enrolled with informed owner consent. Clinical and radiographic parameters were recorded. Either short-term or long-term clinical and radiographic follow-up was required for study inclusion. RESULTS: Four cats and six dogs were enrolled and operated by one of two board-certified surgeons. Bodyweight ranged from 1.9 to 6.6 kg. Number of metabones fractured: all four (60%), three (30%) and two (10%). Anatomical alignment was restored for each metabone. External coaptation was not used in any case. Radiographic follow-up documented clinical or bony union in all cases. Mean time to clinical union was 51 days. One major complication (screw removal) and two minor complications (partial construct failure) were observed. All patients made a complete functional recovery at the time of documented union. Long-term follow-up was available in five cases. No lameness (evaluated independently by both surgeons) or plate sensitivity was noted. CLINICAL SIGNIFICANCE: This is the first clinical evaluation of the VetKISS for metabone fracture repair, and includes long-term follow-up. Results demonstrated complete functional recovery and 100% clinical union rates in all patients, with acceptable complication rates. This system can be considered for metabone repair in patients weighing <7 kg without the use of external coaptation.

Complications and putative risk factors for cecal or colonic surgery in dogs: 79 cases (2002-2015).

OBJECTIVES: To evaluate the complication rate, mortality rate and putative risk factors for cecal or colonic surgery in dogs. MATERIALS AND METHODS: A multi-institutional retrospective study including dogs that had undergone surgery that involved the cecum or the colon. Medical records from three referral hospitals were reviewed for patient demographics and clinical data. The association between putative risk factors and survival to discharge or complications was assessed using univariable and multivariable analysis. RESULTS: Seventy-nine dogs met the criteria to be included in this study. Fifty-five dogs had full thickness incision surgeries, while 24 dogs had partial thickness surgeries. The complication and mortality rates for full thickness and partial thickness cecal/colonic surgeries were not statistically different. The dehiscence rate of colonic anastomosis in this study was four of 47 (8.5%). On univariate analysis, performing full thickness procedures out of hours had an association with increased complications and mortality. On multivariable analysis, no factors were associated with survival to discharge or complications. There was no association of board-certified surgeon presence in surgery with complications or mortality. CLINICAL SIGNIFICANCE: The performance of full thickness cecal/colonic surgery is not associated with a statistically significant increased risk for complications or mortality compared to partial thickness procedures, with a possible increased risk of complications and mortality in full thickness procedures out of hours.

PLANT-Dx: A Molecular Diagnostic for Point-of-Use Detection of Plant Pathogens.

Synthetic biology based diagnostic technologies have improved upon gold standard diagnostic methodologies by decreasing cost, increasing accuracy, and enhancing portability. However, there has been little effort in adapting these technologies toward applications related to point-of-use monitoring of plant and crop health. Here, we take a step toward this vision by developing an approach that couples isothermal amplification of specific plant pathogen genomic sequences with customizable synthetic RNA regulators that are designed to trigger the production of a colorimetric output in cell-free gene expression reactions. We demonstrate our system can sense viral derived sequences with high sensitivity and specificity, and can be utilized to directly detect viruses from infected plant material. Furthermore, we demonstrate that the entire system can operate using only body heat and naked-eye visual analysis of outputs. We anticipate these strategies to be important components of user-friendly and deployable diagnostic systems that can be configured to detect a range of important plant pathogens.

Limited Genetic Variability Among American Isolates of Grapevine virus E from Vitis spp.

A survey for the presence of Grapevine virus E (GVE, genus Vitivirus, family Betaflexiviridae) in vineyards in New York and California was conducted using macroarray hybridization or reverse-transcription polymerase chain reaction (RT-PCR) assays. In New York, GVE was detected in 10 of 46 vines of Vitis labrusca, one V. riparia, and one Vitis hybrid. All GVE-infected New York vines were coinfected with Grapevine leafroll-associated virus-3. In California, GVE was detected in 8 of 417 vines of V. vinifera. All GVE-infected California vines were also coinfected by one of the leafroll-associated viruses and other vitiviruses. In order to assess the genetic diversity among GVE isolates, a viral cDNA was amplified by RT-PCR, and a 675-nucleotide region that included the 3' terminus of the coat protein gene, a short intergenic region, and the 5' terminus of the putative nucleic acid binding protein gene was sequenced. All 20 GVE isolates sequenced in this study were very closely related, with >98% nucleotide identity to the SA94 isolate from South Africa. These findings confirm the presence of GVE in major grape-growing regions of the United States and indicate a very low level of genetic diversity.

Impact of fixation method on postoperative complication rates following surgical stabilization of diaphyseal tibial fractures in cats.

OBJECTIVES: To compare the complication rate between open reduction and internal fixation (ORIF) and external skeletal fixation (ESF) for feline diaphyseal tibial fractures. METHODS: In a retrospective study spanning a 10 year period, 57 feline tibial fractures stabilized via ESF or ORIF were included for analysis and complication rates were compared between the two methods. RESULTS: In the overall study population, 23 (40.4%) cases suffered complications (9 major, 20 minor, 6 with both major and minor). All of the major complications occurred in the ESF group. Complications were more common in cats with ESF (50.0%) while only one (7.7%) of the ORIF cases suffered complications (OR 12.0 [CI: 2.09; 228.10], p = 0.02). Use of postoperative antibiotic medications was identified as a confounder. After adjusting for confounding, stabilization using ESF remained associated with a higher risk of complications (OR = 13.71 [CI: 2.18; 274.25], p = 0.02). Cats with ESF had a longer duration of follow-up (15.6 weeks; 95% CI: 13.0; 18.3) compared to ORIF (9.5 weeks; 95% CI: 6.4; 12.7) (p = 0.003), and a higher number of revisits (mean 3.0; 95% CI: 2.4; 3.6) than the ORIF group (mean 1.6; 95% CI: 0.9; 2.3) (p = 0.002). CLINICAL SIGNIFICANCE: This study demonstrates a significant difference in complication rates between the methods of stabilization, with ESF resulting in a significantly higher complication rate compared to ORIF. Based on these results, it may be prudent to select ORIF for stabilization of feline tibial fractures wherever practical.

Patellar ligament rupture in the dog: repair methods and patient outcomes in 43 cases.

The medical records of dogs receiving surgery for unilateral patellar ligament rupture between 1999 and 2012 at 12 multidisciplinary referral centres were reviewed. Forty-three cases were identified; 26 were traumatic in origin; almost one-third were iatrogenic, of which over three-quarters occurred as a complication following surgical stabilisation of patellar luxation. Treatment involved primary reapposition of the ligament (36 cases). The repair was protected by circumpatellar and/or transpatellar loop(s) of orthopaedic wire, nylon, polypropylene or polydioxanone suture (34 cases). Wire loops were more likely to require surgical removal compared with loops of other materials (P=0.0014). The stifle joint was immobilised postoperatively by the applications of a transarticular external skeletal fixator (taESF) in 17 cases and by external coaptation (EC) in 8 cases; in 18 cases, no postoperative joint immobilisation was provided. Complications specific to the method of immobilisation occurred in seven of the cases with taESF and six of the cases with EC. Revision surgery to address failure of repair was required in five cases. Outcome was classified as acceptable or good in over three-quarters of the cases (31/40) and poor in less than a quarter (9/40). These data highlight patellar ligament rupture as a complication of surgical stabilisation of patellar luxation.

Grapevine red blotch-associated virus Is Widespread in the United States.

Grapevine red blotch disease has been recognized since 2008 as affecting North American grape production. The presence of the newly described Grapevine red blotch-associated virus (GRBaV) is highly correlated with the disease. To more effectively detect and monitor the presence of the virus, a sample processing strategy and multiplex polymerase chain reaction assay were developed. A total of 42 of 113 vine samples collected in or received from seven of the United States were shown to harbor the virus, demonstrating the virus is widely distributed across North America. Phylogenetic analyses of a viral replication-associated protein (Rep) gene fragment from the 42 isolates of GRBaV demonstrated distinct clades of the virus (1 and 2), with clade 1 showing the greatest variability. The full-length genome of six virus isolates was sequenced, and phylogenetic analyses of 14 whole genomes recapitulated results seen for the Rep gene. A comparison of GRBaV genomes revealed evidence of recombination underlying some of the variation seen among GRBaV genomes within clade 1. Phylogenetic analyses of coat and replicase-associated protein sequences among single-stranded DNA viruses showed GRBaV to group within the family Geminiviridae. This grouping is distinct from members of the families Nanoviridae and Circoviridae, with limited significant affinities to both recognized genera and novel plant-infecting, gemini-like viruses.

Molecular characterization of domestic and exotic potato virus S isolates and a global analysis of genomic sequences.

Five potato virus S (PVS) isolates from the USA and three isolates from Chile were characterized based on biological and molecular properties to delineate these PVS isolates into either ordinary (PVS(O)) or Andean (PVS(A)) strains. Five isolates - 41956, Cosimar, Galaxy, ND2492-2R, and Q1 - were considered ordinary strains, as they induced local lesions on the inoculated leaves of Chenopodium quinoa, whereas the remaining three (FL206-1D, Q3, and Q5) failed to induce symptoms. Considerable variability of symptom expression and severity was observed among these isolates when tested on additional indicator plants and potato cv. Defender. Additionally, all eight isolates were characterized by determining the nucleotide sequences of their coat protein (CP) genes. Based on their biological and genetic properties, the 41956, Cosimar, Galaxy, ND2492-2R, and Q1 isolates were identified as PVS(O). PVS-FL206-1D and the two Chilean isolates (PVS-Q3 and PVS-Q5) could not be identified based on phenotype alone; however, based on sequence comparisons, PVS-FL206-1D was identified as PVS(O), while Q3 and Q5 clustered with known PVS(A) strains. C. quinoa may not be a reliable indicator for distinguishing PVS strains. Sequences of the CP gene should be used as an additional criterion for delineating PVS strains. A global genetic analysis of known PVS sequences from GenBank was carried out to investigate nucleotide substitution, population selection, and genetic recombination and to assess the genetic diversity and evolution of PVS. A higher degree of nucleotide diversity (π value) of the CP gene compared to that of the 11K gene suggested greater variation in the CP gene. When comparing PVS(A) and PVS(O) strains, a higher π value was found for PVS(A). Statistical tests of the neutrality hypothesis indicated a negative selection pressure on both the CP and 11K proteins of PVS(O), whereas a balancing selection pressure was found on PVS(A).

A retrospective study of the short-term complication rate following 750 elective elbow arthroscopies.

Arthroscopy is the gold standard for articular surface examination and is commonly advocated for diagnosing and treating cases of canine elbow dysplasia. Arthroscopy is generally regarded as a low-risk procedure, however there is a paucity of information in the small animal veterinary literature regarding the associated complication rates. In a retrospective study spanning a ten year period, 750 elective elbow arthroscopies were evaluated. Complications necessitating repeat surgery were defined as major, and were documented in 4.8% of dogs. Minor perioperative complications occurred in 17.1% dogs. The failure of arthroscopic treatment necessitating unplanned conversion to arthrotomy was the most frequently encountered complication in this category, having been reported in five percent of dogs. Minor postoperative complications occurred in 10.7% dogs; these included a worsened postoperative lameness (5.5%), severe pain (2.8%), severe swelling (2%), infection (0.2%), and neurapraxia (0.2%). A total of 204 dogs returned for a postoperative re-examination and in seven percent, lameness was more severe than that noted preoperatively. The results of the study show that the major complication rate associated with elective elbow arthroscopy is low, but that the minor peri- and postoperative complication rate is concerning. These findings will assist veterinarians in their preoperative discussions with owners to ensure the achievement of informed consent.

Spinach latent virus Infecting Tomato in Virginia, United States.

Plants in a single field of commercial tomato (Solanum lycopersicum) of unidentified cultivars in Virginia in July, 2012, were observed showing stunting, leaf distortion, twisting and thickening, discoloration, and color streaking and ringspots on fruits. Serological tests were negative for Cucumber mosaic virus, Groundnut ringspot virus, Tomato spotted wilt virus, Tomato chlorotic spot virus, Impatiens necrotic spot virus, Tobacco mosaic virus, and Tomato bushy stunt virus (Agdia, Inc., Elkhart, IN). Using a membrane-based macroarray (3), hybridization was observed to 8 of 9 70-mer oligonucleotide probes of Spinach latent virus (SpLV; genus Ilarvirus, family Bromoviridae). To confirm the hybridization results, complementary DNA (cDNA) was synthesized using random hexamers and MMLV reverse transcriptase (Promega, Madison, WI), followed by PCR amplification using ilarvirus degenerate primers (4). Fragments of approximately 380 bp were amplified and directly sequenced (GenBank Accession KC_466090); a BLAST search showed a 99% identity to the SpLV RNA 2 reference genome (NC_003809). Primers for SpLV RNA1 (SpLVRNA1f-GGTGTCACCATGCAAACTGG, SpLVRNA1r-AGCTCTTCGTAATAGGCCTGC) and SpLV RNA3 (SpLVCPf-GAAGTCTTTCCCAGGTGAGCA, SpLVCPr-AGGTGGGCATATGGACTTGG) were designed and cDNA was amplified using the IQ supermix (Biorad, Hercules, CA) with thermocycling of 94°C for 4 min, 35× (94°C 45 s, 55°C 45 s, 72°C 45 s), and 72°C for 10 min. The resulting fragments of 538 bp for RNA1 (KC_466088) and 661 bp for RNA3 (KC_466089) showed 100% identity to reference genome sequences for SpLV (NC_003808 and NC_003810, respectively). To demonstrate virus transmissibility, Chenopodium quinoa plants were mechanically inoculated using tomato leaf material (same source described above) ground in 30 mM Na2HPO4 buffer, pH 7.0. Necrotic spots developed on the inoculated leaves 10 dpi. Younger, non-inoculated leaves showed yellow mottling and tested positive for SpLV by RT-PCR (two of two plants tested). The detection of SpLV is rarely reported, with only one record from the United States (2). Although SpLV is described as a latent virus, it has been found associated with tomato fruit symptoms in New Zealand (1). It is not known if the fruit ringspot and other symptoms on the Virginia samples were due to virus infection. Since SpLV is seed-transmissible and seed production takes place in different parts of the world, it has the potential to spread with germplasm and become more widespread in North America. References: (1) B. S. M. Lebas et al. Plant Dis. 91:228, 2007. (2) H. Y. Liu and J. E. Duffus. Phytopathology 76:1087, 1986. (3) K. L. Perry and X. Lu. Phytopathology 100:S100, 2010. (4) M. Untiveros, et al. J. Virol. Methods 165:97, 2010.

Arabis mosaic virus in Grapevines in New York State.

In a limited survey of commercial vineyards and a germplasm repository in Ontario County, NY, 20 vines of Vitis sp. were tested in fall and spring 2010 to 2012 for viruses using a double-antibody sandwich (DAS)-ELISA and macroarray with oligonucleotide probes for grapevine viruses ((3) and unpublished). The plants selected for analysis included those showing atypical growth including leaf deformation, yellowing, cupping or spotting, vein clearing, shortening of internodes, and reduced vigor. Arabis mosaic virus (ArMV; genus Nepovirus, family Secoviridae) was detected in leaf tissue and wood scrapings in two vines using the DAS-ELISA with antibodies from Bioreba (Reinach, Switzerland). The ArMV positive vines were from Vitis hybrid cultivars Noah and Geisenheim 26. ArMV was also detected in these two vines using the macroarray, with hybridization observed to 24 of 32 oligonucleotide probes specific to this virus. To confirm the identification of the virus, total RNAs were extracted from leaf tissues, hybridized with random hexamers, and reverse-transcribed using MMLV reverse transcriptase (Life Technologies, Grand Island, NY). Complementary DNAs were amplified by PCR using an IQ supermix (BioRad, Hercules, CA), and two sets of generic primers for nepoviruses (1,4). Thermocycler conditions were 94°C 5 min (1×); 94°C 30 s, 50°C 30 s, and 69°C 2 min (35×), and 72°C for 5 min. The PCR products were sequenced directly. Sequences from the 340-bp products obtained from cultivars Geisenheim 26 (GenBank Accession No. HE984333) and Noah (HE984334) using the Wei et al. primers (4) had 76 to 84% sequence identity to ArMV RNA1 GenBank accessions GQ369528 and AY303786. Sequences from the 301-bp products obtained from cultivars Geisenheim 26 (HE984335) and Noah (HE984336) using the Digiaro et al. primers (1) had 87 to 91% sequence identity to ArMV RNA2 GenBank accessions AY017339 and X81814. ArMV was mechanically transmitted from Geisenheim 26 to Nicotiana tabacum cultivar Xanthi NN. Inoculation gave rise to necrotic local lesions on the inoculated leaves of five plants in each of two experiments (10 of 10 plants total). The presence of ArMV in tobacco was confirmed by DAS-ELISA. Thus, the presence of ArMV in New York grapevines has been confirmed by the detection of the coat protein antigen, virus specific oligonucleotide probes, and the sequencing of portions of both genomic RNAs. There are limited reports of ArMV in North America and in grapevine in particular (2), but with a wide host range and seed and nematode transmissibility, ArMV has the ability to become more widespread among grapevine and other crops. References: (1) M. Digiaro, et al. J. Virol. Methods 141:34, 2007. (2) B. N. Milkus et al. Am. J. Enol. Vitic. 50:56, 1999. (3) J. Thompson et al. J. Virol. Methods 183:161, 2012. (4) T. Wei et al. J. Virol. Methods 153:16, 2008.

Management of peristomal tissue necrosis following prepubic urethrostomy in a cat.

This report describes the successful management of peristomal tissue necrosis following prepubic urethrostomy in a cat. The novel technique of temporary urethral ligation was used in combination with temporary tube cystostomy and vacuum assisted closure to allow for wound management prior to performing wound closure by utilization of a flank fold skin flap then definitive prepubic urethrostomy. Eleven month follow-up indicated excellent outcome with the cat having returned to normal behaviour apart from having adapted its posture to urinate.

Transmission Efficiency of Potato virus Y strains PVYO and PVYN-Wi by Five Aphid Species.

Potato virus Y (PVY) is a reemerging problem in potato production in North America. Although the "ordinary" strain, PVYO, is still the dominant isolate in U.S. seed potatoes, the recombinant strain of the virus PVYN-Wi (= PVYN:O) has become widespread. An increase in the prevalence of a PVY strain could be due to differences in the efficiency of transmission by aphid vectors. The transmission efficiency by a clone of Myzus persicae was determined for five isolates each of PVYO and PVYN-Wi. An aphid transmission assay was developed based on the use of potato seedlings from true potato seed, allowing for greater control of plant age and growth stage. No apparent differences in transmission by M. persicae were observed. Single isolates of PVYO and PVYN-Wi were tested for their ability to be transmitted from potato to potato by five aphid species: Aphis glycines, A. gossypii, A. nasturtii, M. persicae, and Rhopalosiphum padi. Both PVY isolates showed a similar transmission phenotype in being transmitted efficiently by M. persicae but very poorly or not at all by A. glycines, A. gossypii, and R. padi. The aphid A. nasturtii transmitted both isolates with an intermediate level of efficiency. The data do not support a model for a differential aphid transmissibility being responsible for the increase in the prevalence of PVYN-Wi.

Potato virus M in Bittersweet Nightshade (Solanum dulcamara) in New York State.

Potato virus M (PVM) was detected in upstate New York in two plants of the widely naturalized, weedy perennial Solanum dulcamara. The virus was detected with a macroarray assay for potato viruses (1). Amplified, complimentary DNAs from the two isolates hybridized to 5 and 7 of the 15 oligonucleotide probes for PVM. Testing of the samples by double-antibody sandwich-ELISA using PVM-specific antibodies (Agdia, Elkhart, IN) showed a clear positive result. Sequence information for a 118-bp genomic region was obtained by amplification using carlavirus-specific primers (2) (GenBank Accession No. HQ446853). Comparison with a reference PVM genome (GenBank Accession No. NC_001361) showed that the sequence corresponded to nucleotide positions 8418 to 8533 with 86% identity. The infected plants were symptomless and collected from two sites, 50 miles apart. One site was a weedy roadside location in Tompkins County in 2009, while the second was from a hedgerow in a (non-potato) vegetable production area of Ontario County in 2010. The virus could be detected throughout the growing season in this perennial host. PVM was reported from S. dulcamara L. in Hungary and described as being found frequently from a diversity of habitats (3). Importantly, the virus was transmitted via tubers and by Myzus persicae with low efficiency (3). These results suggest that the virus may be endemic in S. dulcamara in the northeastern United States and this host may serve as a reservoir for the virus from which it could move into potato. To our knowledge, PVM has not been reported in this host in North America. References: (1) B. Agindotan and K. L. Perry. Plant Dis. 92:730, 2008. (2) J. Badge et al. Eur. J. Plant Pathol. 102:305, 1996. (3) P. Salamon. Eur. Assoc. Pot. Res. Virol. Sect. Meet. 42:121, 2006.

Potato aucuba mosaic virus in Potato in New York State.

Solanum tuberosum cv. Elmer's Blue is one of a number of heritage potato accessions maintained at Cornell University that exhibit virus-like symptoms of stunting and a leaf yellowing or a mottle mosaic. Testing of this cultivar by double-antibody sandwich (DAS)-ELISA revealed that it was infected with Potato virus S (PVS) but none of the other common potato viruses screened for in North American potato certification programs (3). Mechanical inoculation of sap from potato cv. Elmer's Blue onto Nicotiana debneyii, N. megalosiphon, N. occidentalis, and N. tabacum produced a range of yellowing and mosaic symptoms (symptomless on N. tabacum), indicating the presence of a transmissible agent, but all these hosts tested negative for PVS. To identify possible viruses, reverse transcription (RT)-PCR assays involving generic primers for different groups of viruses were performed on the potato and the Nicotiana spp. Degenerate primers specific to members of the genus Potexvirus (4) amplified a 600-bp region from the symptomatic potato and N. debneyii. Nucleotide sequencing of the RT-PCR amplified product from potato cv. Elmer's Blue (Genbank Accession No. EF609120) and comparisons with GenBank sequences revealed the amplified sequence as having 91% identity with the genomic sequence of Potato aucuba mosaic virus (PAMV; Accession No. S73580). The presence of this virus in potato cv. Elmer's Blue and N. debneyii was confirmed by PAMV-specific antibodies (Agdia, Inc., Elkhart, IN) in a DAS-ELISA format. PAMV is reported to occur worldwide, but uncommonly, with most descriptive work from Europe (2). While this virus has been studied in North America (1,2), these reports employed virus stocks from Europe under experimental conditions or virus in tubers obtained directly from Europe; to our knowledge, there are no unambiguous reports of PAMV in naturally infected North American potato cultivars. By contrast, the PAMV-infected cultivar in this report is a selection originally from a Canadian grower, and although not grown commercially, it is maintained in garden and field plots in New York and other states. References: (1) R. H. Bagnall. Phytopathology 50:460, 1960. (2) G. F. Kollmer and R. H. Larson. Res. Bull. Agric. Exp. Stn. Univ. Wis. 223:1, 1960. (3) S. A. Slack. Page 61 in: Potato Health Management. The American Phytopathological Society. St. Paul, MN, 1993. (4) R. A. A. van der Vlugt and M. Berendsen. Eur. J. Plant Pathol. 108:367, 2002.

Biological and Serological Properties of Potato virus Y Isolates in Northeastern United States Potato.

A survey of six potato viruses, Potato virus A (PVA), Potato virus M (PVM), Potato virus S(PVS), Potato virus X (PVX), Potato virus Y (PVY), and Potato leafroll virus (PLRV), was conducted in New York and Maine during 2002 and 2003. Leaf samples were tested by enzyme-linked immunosorbent assay and PVY-positive samples were further tested to determine whether a necrotic strain of PVY (PVYN) or a strain able to induce necrosis in tobacco and in potato tubers (PVYNTN) were present. In both years, PVY and PVS were identified in a majority of the samples, and mixed infections predominated in 83% of the symptomatic leaves in 2002. Of the total 394 PVY-positive samples, 3 reacted with monoclonal antibody (MAb) 1F5 and caused veinal necrosis (VN) in tobacco. Two of these isolates caused tuber necrosis in the potato cv. Yukon Gold. Three PVY isolates reacted with MAb 1F5 but did not cause VN in tobacco, and two caused VN but did not react with MAb 1F5. None of these eight isolates were able to overcome the Ry resistance gene in the potato cultivar Eva, but several were able to overcome the Ny resistance gene found in Allegany. PVYN isolates were not widespread in the northeastern United States; however, several PVY isolates differed from both PVYN and the ordinary strain of PVY and may represent strain recombinants.

Impatiens necrotic spot virus in Greenhouse-Grown Potatoes in New York State.

Impatiens necrotic spot virus (INSV; genus Tospovirus) was detected in experimental greenhouse-grown potatoes (Solanum tuberosum) and Nicotiana benthamiana in New York State in July and August of 2003 and 2004. Potato leaves exhibiting necrotic lesions with a concentric pattern similar to those induced by Tomato spotted wilt virus (1) were observed on cvs. Atlantic, Huckleberry, NY115, and Pentland Ivory. The presence of INSV was confirmed using double-antibody sandwich enzyme-linked immunosorbent assay and a rapid 'ImmunoStrip' assay (Agdia, Inc., Elkhart, IN). INSV-specific sequences were amplified from total RNA extracts using reverse transcription-polymerase chain reaction with 'Tospovirus Group' primers (Agdia, Inc.) and two independently amplified DNAs were sequenced. A common sequence of 355 nucleotides (GenBank Accession No. AY775324) showed 98% identity to coding sequences in an INSV L RNA. The virus was mechanically transmitted to potato and N. benthamiana and could be detected in asymptomatic, systemically infected potato leaves. Stems nodes and leaves were removed from infected potato plants, and sterile in vitro plantlets were established (2). None of the regenerated in vitro plantlets of cvs. Pentland Ivory (6 plantlets) or NY115 (5 plantlets) were infected with INSV. Two of ten regenerated cv. Atlantic plantlets initially tested positive, but INSV could not be detected after 6 months in tissue culture. In vitro tissue culture plantlets could not be established from infected cv. Huckleberry plants, even though they were consistently obtained from uninfected plants. Infected greenhouse plants were grown to maturity and the tubers harvested, stored for 6 months at 4°C, and replanted in the greenhouse. INSV could not be detected in plants from 26 cv. Huckleberry, 4 cv. NY115, or 4 cv. Atlantic tubers. Although this isolate of INSV was able to systemically infect potato, it was not efficiently maintained or transmitted to progeny tubers. This might explain why INSV has not been reported as a problem in potato production. Lastly, in both years, dying N. benthamiana provided the first sign of a widespread greenhouse infestation of INSV in a university facility housing ornamental and crop plants. INSV induced a systemic necrosis in N. benthamiana, and this host may be useful as a sensitive 'trap' plant indicator for natural infections in greenhouse production. References: (1) T. L. German. Tomato spotted wilt virus. Pages 72-73 in: Compendium of Potato Diseases. W. R. Stevenson et al., eds. The American Phytopathological Society, St. Paul, 2001. (2) S. A. Slack and L. A. Tufford. Meristem culture for virus elimination. Pages 117-128 in: Fundamental Methods of Plant Cell, Tissue and Organ Culture and Laboratory Operations. O. L. Gamborg and G. C. Philips, eds. Springer-Velag, Berlin, 1995.

A new potato virus in a new lineage of picorna-like viruses.

On constructing a cDNA library for potato, 'contaminating' sequences with a significant identity to Apple latent spherical virus (ALSV) were found. Determination of the remaining genome sequence indicated the presence of a bipartite virus with an RNA1 and 2 of 7034 and 3315 nucleotides, respectively, excluding a poly(A)tail. RNA1 encodes a single polyprotein (233 kDa) and shares highest amino acid identity with ALSV at 65%. Conserved amino acid motifs typical for helicase, protease and RNA-dependent polymerase (RdRp) functions are present. RNA2 encodes a single polyprotein (106 kDa) with amino acid identities to the flat apple isolate of Cherry rasp leaf virus (CRLV-FA) (97%) and ALSV (70%), suggesting this is a potato strain of CRLV (CRLV-pot). Phylogenetic analysis using the RdRp region shows that this virus falls within a group separate from the Comoviridae that includes members of the Sequiviridae and the taxonomically unassigned viruses ALSV, Strawberry mottle virus, Satsuma dwarf virus and Navel orange infectious mottling virus. Other regions of the genome have highest identities with both plant and animal infecting members of the picorna-like virus superfamily. The evolutionary context of CRLV-pot and related viruses is discussed. Similar viral sequences from an EST library of peppermint are also analysed.

Transmissibility of Field Isolates of Soybean Viruses by Aphis glycines.

During the 2001 growing season, 191 symptomatic soybean (Glycine max (L.) Merr.) plants were dug from production plots in Indiana, Wisconsin, and Kentucky. Alfalfa mosaic virus (AMV), Bean pod mottle virus (BPMV), Bean yellow mosaic virus (BYMV), Peanut stunt virus (PSV), Tobacco ringspot virus (TRSV), and Soybean mosaic virus (SMV) were identified. No mixed infections were observed. The ability of the soybean aphid (Aphis glycines Matsamura) to transmit field isolates of these viruses was tested. Using naturally infected field- or greenhouse-grown soybean plants as sources, six isolates of SMV and two isolates of AMV were transmitted using a short feeding assay. One of two isolates of TRSV was transmitted by A. glycines in one of four experiments using an extended feeding transmission assay. BPMV was not transmitted by A. glycines in assays involving 11 field isolates and over 840 aphids. One field isolate each of BYMV and PSV were tested and no transmission by A. glycines was observed.