225 research outputs found
Susceptibility of Onion Relatives (<i>Allium</i> spp.) to <i>Iris yellow spot virus</i>
No full text Iris yellow spot virus (IYSV; family Bunyaviridae, genus Tospovirus) is becoming an increasingly important constraint to the production of bulb and seed onions (Allium cepa L.) in many onion-growing regions of the continental United States and the world (4). During an evaluation of onion germplasm for susceptibility to IYSV, six other Allium species (A. altaicum, A. galanthum, A. roylei, A. schoenoprasum, A. tuberosum, and A. vavilovii) were also evaluated under natural field conditions. In July 2010, symptoms suggestive of IYSV infection (straw-colored necrotic lesions) were observed on leaves of these Allium spp. in experimental plots in Las Cruces, NM. IYSV was detected in symptomatic leaves of A. altaicum, A. vavilovii, A. tuberosum, A. schoenoprasum and A. roylei with a commercially available ELISA kit (Agdia Inc., Elkhart, IN). IYSV infection was confirmed by reverse transcription (RT)-PCR with forward and complementary primers 5′-CTCTTAAACACATTTAACAAGCAC-3′ and 5′-TAAAACAAACATTCAAACAA-3′ flanking the nucleocapsid (N) gene encoded by the small RNA of IYSV as previously described (1,3). Amplicons, approximately 1.1 kb long, were obtained from all symptomatic Allium spp. samples but not from healthy samples or water controls. Sequencing of selected amplicons confirmed IYSV infection. The highest nucleotide identity of 98% was shared with IYSV isolates from Japan (GenBank Accession No. AB180921). A. altaicum, A. vavilovii, and A. pskemense were previously reported from Washington to be susceptible to IYSV (2). Current findings expand the list of Allium spp. that are susceptible to IYSV and underscores the need for continued screening of other members of the genus to find sources of resistance to IYSV. References: (1) H. R. Pappu et al. Arch. Virol. 151:1015, 2006. (2) H. R. Pappu et al. Plant Dis. 90:378, 2006. (3) H. R. Pappu et al. Plant Dis. 92:588, 2008. (4) H. R. Pappu et al. Virus Res. 141:219, 2009. </jats:p
First report of natural infection of Agapanthus sp. by Eggplant mottled dwarf virus (EMDV)
No full textCOMPLETE GENOMIC CHARACTERIZATION OF EGGPLANT MOTTLED DWARF VIRUS FROM AGAPANTHUS sp. BY DEEP SEQUENCING AND DE NOVO ASSEMBLY
No full textA consumer-based method for retailer equity measurement: results of an empirical study
No full textThis research extends the consumer-based brand equity measurement approach to the measurement of the equity associated with retailers. This paper also addresses some of the limitations associated with current retailer equity measurement such as a lack of clarity regarding its nature and dimensionality. We conceptualise retailer equity as a four-dimensional construct comprising retailer awareness, retailer associations, perceived retailer quality, and retailer loyalty. The paper reports the result of an empirical study of a convenience sample of 601 shopping mall consumers at an Australian state capital city. Following a confirmatory factor analysis using structural equation modelling to examine the dimensionality of the retailer equity construct, the proposed model is tested for two retailer categories: department stores and speciality stores. Results confirm the hypothesised four-dimensional structure.Ravi Pappu, Pascale Questerhttp://www.elsevier.com/wps/find/journaldescription.cws_home/30446/description#descriptio
Differentiation of Biologically Distinct Peanut Stripe Potyvirus Strains by a Nucleotide Polymorphism-Based Assay
No full textA necrotic strain of peanut stripe potyvirus (PStV-Ts) was used to design and test strain-differentiating oligonucleotides. The 3' region of PStV-Ts, including a part of the NIb, region, the complete coat protein (CP) gene, and the 3'-untranslated region, was cloned and sequenced. PStV-Ts had a high degree of sequence identity (92 to 95%) to the known non-necrotic (blotch) strains both at the nucleotide and amino acid sequence levels. Nucleotide sequence differences unique to the necrotic strain were identified when compared to the available non-necrotic isolates of PStV. Nucleotide polymorphism in the CP gene sequences was utilized in designing oligonucleotides that were specific to the necrotic strain, and were employed in an assay to differentiate the necrotic strain from non-necrotic. The 3' end mismatch in the oligonucleotides contributed in particular to the differentiation of the strains. This approach facilitated rapid, sensitive, and reliable detection and differentiation of PStV strains
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First Report of Natural Infection of Garlic with Iris yellow spot virus in the United States
No full textIris yellow spot virus (IYSV; family Bunyaviridae, genus Tospovirus) is an important constraint to onion bulb and seed production in several onion-growing regions of the United States (1,3). While garlic (Allium sativum) was reported to be infected with IYSV in Réunion Island (4), there have been no confirmed reports of natural infection of garlic in the United States. Garlic plants showing near-diamond-shaped lesions were found in August of 2008 in Marion County, Oregon. The 0.4046-ha (1-acre) field plot consisted of various true-seeded garlic varieties and was adjacent to three onion fields that showed IYSV symptoms. Symptoms were observed on 5% of the garlic plants with most of the symptomatic plants displaying small and diffuse straw-colored spots. Seven of these symptomatic plants were selected for testing. Of these, two showed characteristic diamond-shaped, elongated, straw-colored lesions on garlic scapes. However, the lesions were more diffuse with less-defined edges compared with the characteristic diamond-shaped lesions that are often associated with IYSV infection (1). All symptomatic plants were positive for IYSV by double-antibody sandwich-ELISA with a commercially available kit (Agdia Inc., Elkhart, IN). To verify IYSV infection, total nucleic acid extracts from the symptomatic parts of the leaves were prepared and tested for the presence of IYSV by reverse transcription (RT)-PCR with primers 5′-TAAAACAAACATTCAAACAA-3′ and 5′-CTCTTAAACACATTTAACAAGCAC-3′, which flank the nucleocapsid (N) gene coded by the small RNA of IYSV (2). An approximate 1.1-kb amplicon was obtained from all symptomatic plants and cloned and sequenced. Nucleotide sequence comparisons using BLAST showed that a consensus of three clones derived from the amplicon from garlic (No. FJ514257) was 85 to 99% identical with IYSV sequences available in GenBank (Nos. AF001387, AB180918, and AB286063), confirming the identity of IYSV. To our knowledge, this is the first report of natural infection of IYSV infection of garlic in the United States. Additional surveys and testing are needed to obtain a better understanding of IYSV incidence in garlic to evaluate its impact on garlic production. References: (1) D. Gent et al. Plant Dis. 90:1468, 2006. (2) H. R. Pappu et al. Arch. Virol. 151:1015, 2006. (3) H. R. Pappu et al. Virus Res. 141:219, 2009. (4) I. Robène-Soustrade et al. Plant Pathol. 55:288, 2006
First Report of <i>Iris yellow spot virus</i> Infecting Onion in Kenya and Uganda
No full text Onion (Allium cepa L.) is one of the key vegetables produced by small-holder farmers for the domestic markets in Sub-Saharan Africa. Biotic factors, including infestation by thrips pests such as Thrips tabaci Lindeman, can inflict as much as 60% yield loss. Iris yellow spot virus (IYSV; family Bunyaviridae, genus Tospovirus) transmitted by T. tabaci is an economically important viral pathogen of bulb and seed onion crops in many onion-growing areas of the world (2,4). In Africa, IYSV has been reported in Reunion (1) and South Africa (3). In September 2009, symptoms suspected to be caused by IYSV were observed on onions and leeks cultivated in Nairobi, Kenya. Symptoms consisted of spindle-shaped, straw-colored, irregular chlorotic lesions with occasional green islands on the leaves. The presence of the virus was confirmed with IYSV-specific Agdia Flash kits (Agdia Inc., Elkart, IN). Subsequently, surveys were undertaken in small-holder farms in onion production areas of Makueni (January 2010) and Mwea (August 2010) in Kenya and Kasese (January 2010) and Rwimi (January 2010) in Uganda. The incidence of disease in these locations ranged between 27 and 72%. Onion leaves showing symptoms of IYSV infection collected from both locations tested positive for the virus by double-antibody sandwich-ELISA with IYSV-specific antiserum (Agdia Inc). IYSV infection was confirmed by reverse transcription-PCR with primers IYSV-465c: 5′-AGCAAAGTGAGAGGACCACC-3′ and IYSV-239f: 5′-TGAGCCCCAATCAAGACG3′ (3) as forward and reverse primers, respectively. Amplicons of approximately 240 bp were obtained from all symptomatic test samples but not from healthy and water controls. The amplicons were cloned and sequenced from each of the sampled regions. Consensus sequence for each isolate was derived from at least three clones. The IYSV-Kenya isolate (GenBank Accession No. HQ711616) had the highest nucleotide sequence identity of 97% with the corresponding region of IYSV isolates from Sri Lanka (GenBank Accession No. GU901211), followed by the isolates from India (GenBank Accession Nos. EU310287 and EU310290). The IYSV-Uganda isolate (GenBank Accession No. HQ711615) showed the highest nucleotide sequence identity of 95% with the corresponding region of IYSV isolates from Sri Lanka (GenBank Accession No. GU901211) and India (95% with GenBank Accession Nos. EU310274 and EU310297). To our knowledge, this is the first report of IYSV infecting onion in Kenya and Uganda. Further surveys and monitoring of IYSV incidence and distribution in the region, along with its impact on the yield, are under investigation. References: (1) L. J. du Toit et al. Plant Dis. 91:1203, 2007. (2) D. H. Gent et al. Plant Dis. 88:446, 2004. (3) H. R. Pappu et al. Plant Dis 92:588, 2008. (4) H. R. Pappu et al. Virus Res. 141:219, 2009. </jats:p
Pappulab/N130-Liquid-Structure: Biomolecular condensates form spatially inhomogeneous network fluids
No full text<p>This repository contains the data for the Nature Communications manuscript, "Biomolecular condensates form spatially inhomogeneous network fluids" by F. Dar†, S. R. Cohen†, D. M. Mitrea, A. H. Phillips, G. Nagy, W. C. Leite, C. B. Stanley, J-M. Choi†,§, R. W. Kriwacki§, R. V. Pappu§. (†Equal contributors; §Co-corresponding authors). (2024).</p>
<p>For accompanying analysis scripts, please consult: https://github.com/Pappulab/n130-liquid-structure .</p>
Pappulab/N130-Liquid-Structure: Biomolecular condensates form spatially inhomogeneous network fluids
No full text<p>This repository contains the data for the Nature Communications manuscript, "Biomolecular condensates form spatially inhomogeneous network fluids" by F. Dar†, S. R. Cohen†, D. M. Mitrea, A. H. Phillips, G. Nagy, W. C. Leite, C. B. Stanley, J-M. Choi†,§, R. W. Kriwacki§, R. V. Pappu§. (†Equal contributors; §Co-corresponding authors). (2024).</p>
<p>For accompanying analysis scripts, please consult: https://github.com/Pappulab/n130-liquid-structure .</p>
Pappulab/N130-Liquid-Structure: Biomolecular condensates form spatially inhomogeneous network fluids
No full text<p>This repository contains the data for the Nature Communications manuscript, "Biomolecular condensates form spatially inhomogeneous network fluids" by F. Dar†, S. R. Cohen†, D. M. Mitrea, A. H. Phillips, G. Nagy, W. C. Leite, C. B. Stanley, J-M. Choi†,§, R. W. Kriwacki§, R. V. Pappu§. (†Equal contributors; §Co-corresponding authors). (2024).</p>
<p>For accompanying analysis scripts, please consult: https://github.com/Pappulab/n130-liquid-structure .</p>
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