| identification and characterization of plasmids from the western aster yellows mycoplasmalike organism. | supercoiled double-stranded dna molecules (plasmids) were isolated from plants infected with three laboratory strains of western aster yellows mycoplasma-like organism (ay-mlo) by using cesium chloride-ethidium bromide density gradients. southern blot analysis, using plasmids from the severe strain of ay-mlo (say-mlo) as the probe, identified at least four plasmids in celery, aster, and periwinkle plants and in macrosteles severini leafhopper vectors infected with either the dwarf ay-mlo, tulela ... | 1990 | 2307660 |
| geminivirus coat protein gene replacement alters insect specificity. | chimeric clones have been constructed in which the coat protein encoded by dna a of the bipartite genome of the geminivirus african cassava mosaic virus (acmv) has been replaced by that of beet curly top virus (bctv). constructs containing the coding region inserted in either orientation were infectious when co-inoculated with acmv dna b onto nicotiana benthamiana, producing symptoms typical of acmv infection. the onset of symptom production was delayed relative to plants inoculated with parenta ... | 1990 | 2353465 |
| field ecology of spiroplasma citri in western north america. | spiroplasma citri naturally infects plants representing several dicotyledonous families in the southwestern u.s., where it is commonly found in old world brassicaceous weeds and cole crop plants as well as in citrus. of its leafhopper vectors, it is most frequently found in circulifer tenellus (baker). it is rarely found in field-collected scaphytopius nitridus (delong), one of two species of scaphytopius capable of transmission from plants in the laboratory. spiroplasmas presumed to be s. citri ... | 1984 | 6392182 |
| mycoplasma infections of plants. | plants can be infected by two types of wall-less procaryotes, spiroplasmas and mycoplasma-like organisms (mlo), both located intracellularly in the phloem tissues of affected plants. spiroplasmas have been cultured, characterized and shown to be true members of the class mollicutes. mlo have not yet been cultured or characterized; they are thought to be mycoplasma-like on the basis of their ultrastructure as seen in situ, their sensitivity to tetracycline and resistance to penicillin. mycoplasma ... | 1981 | 7287398 |
| extensive chromosome aberrations in spiroplasma citri strain br3. | genetic variations in the plant pathogen, spiroplasma citri strain br3, were characterized through physical genome mapping of the original isolate, br3-3x, and two derivatives, br3-t and br3-g, obtained after several years of different maintenance conditions. br3-t was transmitted from plant to plant via its natural insect vector, the leafhopper circulifer tenellus, while br3-g was maintained only in plants by periodic grafting and has lost its ability to be insect transmitted. by pulsed field g ... | 1996 | 8894049 |
| development and use of an established cell line of the leafhopper circulifer tenellus to characterize spiroplasma citri-vector interactions. | a continuous cell line of embryonic origin from the leafhopper circulifer tenellus, ct 1, was established using a protocol modified from thrips cell culture. the line was used to develop an in vitro model to examine the mode of entry of the plant pathogenic mollicute spiroplasma citri into insect host cells. confluent monolayers were achieved in 5-6 months using a simple medium developed for maintaining established leafhopper cell lines. the newly established ct 1 line, and that of another leafh ... | 1998 | 9709012 |
| a century of plant virus management in the salinas valley of california, 'east of eden'. | the mild climate of the salinas valley, ca lends itself well to a diverse agricultural industry. however, the diversity of weeds, crops and insect and fungal vectors also provide favorable conditions for plant virus disease development. this paper considers the incidence and management of several plant viruses that have caused serious epidemics and been significant in the agricultural development of the salinas valley during the 20th century. beet curly top virus (bctv) almost destroyed the newl ... | 2000 | 11137170 |
| characterization of spiroplasma citri adhesion related protein sarp1, which contains a domain of a novel family designated sarpin. | transmission of the plant pathogen spiroplasma citri by its leafhopper vector, circulifer tenellus, involves adherence to and invasion of insect host cells. the s. citri adhesion related protein p89 (sarp1) was purified by immunoprecipitation using anti-sarp1 monoclonal antibodies. the protein's n-terminal amino acid sequence was determined and used to design a degenerate oligonucleotide. the labeled oligonucleotide hybridized to a 3.5 kb mboi fragment from s. citri dna, which was then cloned an ... | 2001 | 11574152 |
| adaptation from whitefly to leafhopper transmission of an autonomously replicating nanovirus-like dna component associated with ageratum yellow vein disease. | ageratum yellow vein disease is caused by the whitefly-transmitted monopartite begomovirus ageratum yellow vein virus and a dna beta satellite component. naturally occurring symptomatic plants also contain an autonomously replicating nanovirus-like dna 1 component that relies on the begomovirus and dna beta for systemic spread and whitefly transmission but is not required for maintenance of the disease. here, we show that systemic movement of dna 1 occurs in nicotiana benthamiana when co-inocula ... | 2002 | 11907341 |
| sequence analysis of two plasmids from the phytoplasma beet leafhopper-transmitted virescence agent. | the complete nucleotide sequences of the two plasmids from the phytoplasma beet leafhopper-transmitted virescence agent (bltva) have been determined. the larger plasmid, pbltva-1, was 10 785 nt in length and contained 11 putative orfs, almost all of which were duplicated or triplicated on the plasmid due to the presence of large repeated regions. the sequence contained a series of tandem repeats, the largest of which was 338 nt long. the sequences of orfs 4 and 11 showed homology with the replic ... | 2004 | 15184567 |
| clover proliferation phytoplasma: 'candidatus phytoplasma trifolii'. | clover proliferation phytoplasma (cpr) is designated as the reference strain for the cp phylogenetic group or subclade, on the basis of molecular analyses of genomic dna, the 16s rrna gene and the 16s-23s spacer region. other strains related to cpr include alfalfa witches'-broom (awb), brinjal little leaf (bll), beet leafhopper-transmitted virescence (bltv), illinois elm yellows (iley), potato witches'-broom (pwb), potato yellows (py), tomato big bud in california (tbbc) and phytoplasmas from fr ... | 2004 | 15280313 |
| association of beet leafhopper (hemiptera: cicadellidae) with a clover proliferation group phytoplasma in columbia basin of washington and oregon. | at least 16 taxa of cicadellids and delphacids were tested by polymerase chain reaction (pcr) for the presence of a phytoplasma in the clover proliferation group, designated 16srvi. nucleic acid extracts from individual insects or groups of 5-10 were tested using pcr primers designed from the dna sequence of 16s-23s rrna or ribosomal protein genes of the pathogen. the beet leafhopper, circulifer tenellus (baker), was most often associated with the phytoplasma, with approximately 16% of the insec ... | 2005 | 15889714 |
| identification of regions of the beet mild curly top virus (family geminiviridae) capsid protein involved in systemic infection, virion formation and leafhopper transmission. | plant viruses in the genus curtovirus (family geminiviridae) are vectored by the beet leafhopper (circulifer tenellus) and cause curly top disease in a wide range of dicotyledonous plants. an infectious clone of an isolate of beet mild curly top virus (bmctv-[w4]), associated with an outbreak of curly top in pepper and tomato crops, was characterized and used to investigate the role of the capsid protein (cp) in viral biology and pathogenesis. frameshift mutations were introduced into the overla ... | 2005 | 16085227 |
| sequence comparisons of plasmids pbjs-o of spiroplasma citri and psku146 of s. kunkelii: implications for plasmid evolution. | spiroplasma citri br3-3x and s. kunkelii cr2-3x cause serious diseases worldwide on citrus and maize species, respectively. s. citri br3-3x harbors a plasmid, pbjs-original (pbjs-o), that encodes the spiroplasma adhesion related protein 1 (sarp1), a protein implicated in binding of the pathogen to cells of its leafhopper vector, circulifer tenellus. the s. kunkelii cr2-3x plasmid, psku146, encodes a homolog of sarp1, sk-arp1. due to the close phylogenetic relationship of the two pathogens, we hy ... | 2005 | 16336638 |
| genetic interrelatedness among clover proliferation mycoplasmalike organisms (mlos) and other mlos investigated by nucleic acid hybridization and restriction fragment length polymorphism analyses. | dna was isolated from clover proliferation (cp) mycoplasmalike organism (mlo)-diseased periwinkle plants (catharanthus roseus (l.) g. don.) and cloned into psp6 plasmid vectors. cp mlo-specific recombinant dna clones were biotin labeled and used as probes in dot hybridization and restriction fragment length polymorphism analyses to study the genetic interrelatedness among cp mlo and other mlos, including potato witches'-broom (pwb) mlo. results from dot hybridization analyses indicated that both ... | 1991 | 16348604 |
| beet leafhopper (hemiptera: cicadellidae) settling behavior, survival, and reproduction on selected host plants. | experiments were conducted to determine the settling behavior, survival, and reproduction of the beet leafhopper, circulifer tenellus (baker), when maintained on selected host plants. this leafhopper was recently identified in the columbia basin of washington and oregon as the probable vector of the beet leafhopper-transmitted virescence agent phytoplasma, causal agent of several vegetable crop diseases, including potato purple top. plants selected for study were sugar beet, beta vulgaris l.; ra ... | 2005 | 16539100 |
| comparative analysis of the plasmids from two isolates of "candidatus phytoplasma australiense". | two plasmids from the plant-pathogenic mollicute "candidatus phytoplasma australiense" were completely sequenced from two isolates derived from different plant hosts. plasmid ppaph2 (3607bp) was obtained from phormium showing phormium yellow leaf symptoms and ppasb11 (3635bp) from strawberry showing strawberry lethal yellows symptoms. the plasmids varied in their copy number and nucleotide sequence yet contained the same four open reading frames (orfs). the deduced amino acid sequence derived fr ... | 2006 | 16620976 |
| beet leafhopper (hemiptera: cicadellidae) transmits the columbia basin potato purple top phytoplasma to potatoes, beets, and weeds. | experiments were conducted to determine whether the beet leafhopper, circulifer tenellus (baker) (hemiptera: cicadellidae), transmits the purple top phytoplasma to potato, solanum tuberosum l.; beets, beta vulgaris l.; and selected weed hosts. the beet leafhopper-transmitted virescence agent (bltva) phytoplasma was identified as the causal agent of the potato purple top disease outbreaks that recently occurred in the columbia basin of washington and oregon. the phytoplasma previously was found t ... | 2006 | 16686123 |
| distribution and rate of movement of the curtovirus beet mild curly top virus (family geminiviridae) in the beet leafhopper. | abstract a polymerase chain reaction (pcr)-based method for the detection of the curtovirus beet mild curly top virus (bmctv, previously named the worland strain of beet curly top virus) was developed and used to investigate the bmctv-beet leafhopper interaction. using pcr and a bmctv-specific primer pair, an approximately 1.1-kb bmctv dna fragment was amplified from adult leafhoppers and from the organs involved in circulative transmission: the digestive tract, hemolymph, and salivary glands. t ... | 2003 | 18944363 |
| spiroplasma citri surface protein p89 implicated in adhesion to cells of the vector circulifer tenellus. | abstract two microtiter plate assays were developed to study the adherence of the plant-pathogenic mollicute spiroplasma citri to a monolayer of cultured cells of its leafhopper vector, circulifer tenellus. adherence was significantly reduced by prior treatment of the spiroplasmas with proteinase k or pronase. electrophoresis and western blotting of spiroplasma membrane proteins, before and after exposure of intact spiroplasmas to proteases, revealed the concomitant reduction in intensity of a m ... | 2000 | 18944490 |
| spiroplasma citri movement into the intestines and salivary glands of its leafhopper vector, circulifer tenellus. | abstract spiroplasma citri, a helical, wall-less prokaryote in the class molli-cutes, is transmitted by the beet leafhopper, circulifer tenellus. invasion of leafhopper tissues and cytopathological effects by s. citri were investigated by transmission electron microscopy. all eight cell types of the principle salivary glands, as well as the adjacent muscle cells and the cells of the accessory salivary glands, were colonized by the spiroplas-mas. in both midgut epithelia and salivary gland cells, ... | 1999 | 18944638 |
| transmission of different isolates of spiroplasma citri to carrot and citrus by circulifer tenellus (hemiptera: cicadellidae). | carrot purple leaf disease was first reported in 2006 in the state of washington and was associated with spiroplasma citri. the disease also was reported in california in 2008. the objectives of this work were to fulfill koch's postulates and to determine 1) whether the beet leafhopper, circulifer tenellus (baker) (hemiptera: cicadellidae), transmits carrot [daucus carota l. subsp. sativus (hoffm.) arcang] isolates of s. citri; and 2) whether carrot and citrus [citrus sinensis (l.) osb.]-derived ... | 2009 | 19736751 |
| plant-feeding insects harbor double-stranded rna viruses encoding a novel proline-alanine rich protein and a polymerase distantly related to that of fungal viruses. | novel double-stranded rnas (approximately 8 kbp) were isolated from threecornered alfalfa hopper (spissistilus festinus) and beet leafhopper (circulifer tenellus), two plant-feeding hemipteran insect pests. the two new viruses, designated spissistilus festinus virus 1 (spfv1) and circulifer tenellus virus 1 (citv1), do not appear to be encapsidated in conventional virions and shared a genome organization similar to that of several unclassified fungal viruses. spfv1 and citvl encode a proline-ala ... | 2010 | 20541786 |
| incidence of the beet leafhopper-transmitted virescence agent phytoplasma in local populations of the beet leafhopper, circulifer tenellus, in washington state. | phytoplasma diseases are increasingly becoming important in vegetable crops in the pacific northwest. recently, growers in the columbia basin and yakima valley experienced serious outbreaks of potato purple top disease that caused significant yield loss and a reduction in tuber processing quality. it was determined that the beet leafhopper-transmitted virescence agent (bltva) phytoplasma was the causal agent of the disease in the area and that this pathogen was transmitted by the beet leafhopper ... | 2010 | 20578882 |
| genetic diversity in curtoviruses: a highly divergent strain of beet mild curly top virus associated with an outbreak of curly top disease in pepper in mexico. | a full-length curtovirus genome was pcr-amplified and cloned from peppers in mexico with symptoms of curly top disease. the cloned dna of this isolate, mx-p24, replicated in nicotiana tabacum protoplasts and was infectious in n. benthamiana plants. sequence analysis revealed that the mx-p24 isolate had a typical curtovirus genome organization and was most similar to beet mild curly top virus (bmctv). however, sequence identities were at the threshold value for establishment of a new curtovirus s ... | 2010 | 21193937 |
| selection and characterization of spiroplasma citri mutants by random transposome mutagenesis. | phytopathogenic spiroplasmas can multiply in vascular plants and insects. a deeper understanding of this dual-host life could be furthered through the identification by random mutagenesis of spiroplasma genes required. the ability of the ez::tn™ <dhfr-1> tnp transposome™ system to create random insertional mutations in the genome of spiroplasma citri was evaluated. the efficiency of electroporation-mediated transformation of s. citri br3-3x averaged 28.8 cfus/ng transposome for 10(9) spiroplasma ... | 2011 | 21635220 |
| mutational analysis of the monopartite geminivirus beet curly top virus. | mutants of the monopartite geminivirus beet curly top virus have been screened for infectivity and symptom development in nicotiana benthamiana and beta vulgaris, for replication competence in n. benthamiana leaf discs, and for transmission by the leafhopper circulifer tenellus. disruption of open reading frame (orf) v2 by the introduction of a termination codon resulted in symptomless infection of n. benthamiana associated with low levels of virus and reduced single-stranded (ss) dna and preven ... | 1992 | 1413511 |
| genetic characterization of novel putative rhabdovirus and dsrna virus from japanese persimmon. | deep-sequencing analysis of nucleic acids from leaf tissue of japanese persimmon trees exhibiting fruit apex disorder in some fruits detected two molecules that were graft transmitted to healthy seedlings. one of the complete genomes consisted of 13 467 nt and encoded six genes similar to those of plant rhabdoviruses. the virus formed a distinct cluster in the genus cytorhabdovirus with lettuce necrotic yellows virus, lettuce yellow mottle virus and strawberry crinkle virus in a phylogenetic tre ... | 2013 | 23704275 |
| seasonal population dynamics of three potato pests in washington state. | pest phenology models allow producers to anticipate pest outbreaks and deploy integrated pest management (ipm) strategies. phenology models are particularly useful for cropping systems with multiple economically damaging pests throughout a season. potato (solanum tuberosum l.) crops of washington state, usa, are attacked by many insect pests including the potato tuberworm (phthorimaea operculella zeller), the beet leafhopper (circulifer tenellus baker), and the green peach aphid (myzus persicae ... | 2016 | 27271946 |
| occurrence, sequence polymorphism and population structure of circulifer tenellus virus 1 in a field population of the beet leafhopper. | circulifer tenellus virus 1 (citv1) is the prototypical example of an unusual group of dsrna viruses associated with insects and for which ecological data are lacking. a san joaquin valley (sjv), california population of the beet leafhopper (blh; circulifer tenellus [baker]) was sampled for citv1 in 2010. among 365 blh sampled, 119 (32.6%) were positive for citv1, with at least one citv1-positive blh collected from each of 35 locations. chi-square tests indicated that observed citv1 incidence di ... | 2013 | 23845300 |
| sterilization of the beet leafhopper: induction of sterility and evaluation of biotic effects with a model sterilant (om-53139) and 60 co irradiation. | | 1971 | 5122327 |
| some factors affecting the insecticidal action of pyrethrum extracts on the beet leafhopper. | | 1945 | 21004939 |
| an improved technique for the artificial feeding of the beet leafhopper with notes on its ability to synthesize glycerides. | | 1934 | 17780063 |
| a method of artificially feeding the sugar-beet leafhopper. | | 1932 | 17784241 |