| simple and rapid preparation of infected plant tissue extracts for pcr amplification of virus, viroid, and mlo nucleic acids. | a rapid, simple method for preparing plant tissues infected with viruses, viroids, or mlos using a commercial product known as gene releaser is described. the gene releaser polymeric matrix method produced plant extracts suitable for pcr amplification without the use of organic solvents, ethanol precipitation, or additional nucleic acid purification techniques. modification of maceration methods and/or extraction buffers resulted in the pcr amplification of potato spindle tuber, apple scar skin, ... | 1994 | 7868647 |
| sensitive detection of grapevine virus a, b, or leafroll-associated iii from viruliferous mealybugs and infected tissue by cdna amplification. | dna primers specific for grapevine virus a (gva), grapevine virus b (gvb) or grapevine leafroll-associated virus iii (glrav-iii) were constructed based on the nucleotide sequence of a segment of each viral genome. dna primers were utilized for cdna synthesis and polymerase chain reaction (pcr) amplification of a 430 bp fragment from extracts of gva-infected grapevine tissue or viruliferous mealybugs and 450 bp and 340 bp dna fragments from extracts of gvb and glrav-iii-infected grapevine tissues ... | 1994 | 8051225 |
| nucleotide sequence and genome organization of grapevine leafroll-associated virus-2 are similar to beet yellows virus, the closterovirus type member. | the entire genome of grapevine leafroll-associated closterovirus-2 (glrav-2), except the exact 5' terminus, was cloned and sequenced. the sequence encompasses nine open reading frames (orfs) which include, in the 5' to 3' direction, an incomplete orf1a encoding a putative viral polyprotein and eight orfs that encode proteins of 52 kda (orf1b), 6 kda (orf2), 65 kda (orf3), 63 kda (orf4), 25 kda (orf5), 22 kda (orf6), 19 kda (orf7) and 24 kda (orf8) respectively, and 216 nucleotides of the 3' untr ... | 1998 | 9603345 |
| nucleotide sequence of the 3'-terminal two-thirds of the grapevine leafroll-associated virus-3 genome reveals a typical monopartite closterovirus. | the rna genome of grapevine leafroll-associated closterovirus-3 (glrav-3) was cloned as a cdna generated from glrav-3-specific dsrna, and a partial genome sequence of 13154 nucleotides (nt) including the 3' terminus was determined. the sequenced portion contained 13 open reading frames (orfs) potentially encoding, in the 5'-3' direction, proteins of > 77 kda (orf1a; helicase, hel), 61 kda (orf1b; rna-dependent rna polymerase, rdrp), 6 kda (orf2), 5 kda (orf3, small transmembrane protein), 59 kda ... | 1998 | 9603346 |
| a strategy for rapid cdna cloning from double-stranded rna templates isolated from plants infected with rna viruses by using taq dna polymerase. | a fast and efficient cdna cloning procedure for plant rna viruses was developed. in this procedure, double-stranded rna (dsrna) was used as a template source. standard cdna synthesis reagents and random hexamers were then used for making cdnas. taq dna polymerase was used to add additional (a) at the ends of cdnas, a ta cloning kit to ligate the cdnas to vectors, and an electroporator to transform the dnas to e. coli cells. dsrnas were extracted from grapevine tissues infected with four differen ... | 2000 | 10644087 |
| nucleotide sequence and organization of ten open reading frames in the genome of grapevine leafroll-associated virus 1 and identification of three subgenomic rnas. | the genome of grapevine leafroll-associated virus 1 (glrav-1) was cloned and the sequence of 12394 nts determined. it contains 10 major open reading frames (orfs) and a 3'-non-coding region lacking a poly(a) tract. the first orf (orf 1a) encodes a putative rna helicase at the c-terminal portion of an apparently larger protein. the downstream orf, 1b, overlaps orf 1a and lacks an initiation codon. this orf encodes an rna-dependent rna polymerase of m(r) 59276. orf 2 encodes a small hydrophobic pr ... | 2000 | 10675398 |
| partial sequence identification of grapevine-leafroll-associated virus-1 and development of a highly sensitive ic-rt-pcr detection method. | using immunocapture reverse transcription pcr (ic-rt-pcr) a specific pcr product from glrav-1 infected vine samples was amplified with the help of degenerate primers deduced from the conserved hsp70 region of closteroviruses. 511 basepairs of the 5'end of glrav-1 hsp70 gene were identified. within this region, putative glrav-1 specific primers were designed and an ic-rt-pcr detection procedure was developed which is about 125 times more sensitive than the established elisa method. no pcr product ... | 2000 | 10713381 |
| improved rna extraction and one-tube rt-pcr assay for simultaneous detection of control plant rna plus several viruses in plant extracts. | a procedure was developed for simultaneous detection of plant rna viruses and of plant rna, as a control. rt-pcr amplification with primers designed for the detection of the plant mrnas encoding malate dehydrogenase (mdh) and the large subunit of ribulose bisphosphate carboxylase oxygenase (rubiscol) was used for the development of a plant extraction procedure that consistently yields extracts that can be amplified. the control amplification was used successfully on extracts from cane, leaf and/ ... | 2000 | 11011079 |
| nucleotide sequence, genome organization and phylogenetic analysis of pineapple mealybug wilt-associated virus-2. | the genome of pineapple mealybug wilt-associated closterovirus-2 (pmwav-2) was cloned from double-stranded rna isolated from diseased pineapple and its sequence determined. the 3'-terminal 14861 nt of the single-stranded rna genome contains ten open reading frames (orfs) which, from 5' to 3', potentially encode a >204 kda polyprotein containing papain-like protease, methyltransferase and helicase domains (orf1a), a 65 kda rna-dependent rna polymerase (orf1b), a 5 kda hydrophobic protein (orf2), ... | 2001 | 11125151 |
| hypervariable genes in grapevine leafroll associated virus 1. | analysis of nucleotide sequences of 10 open reading frames from the grapevine leafroll associated virus 1 (glrav-1), a tentative member of the genus closterovirus, revealed the presence of an unusually high degree of sequence variation in orfs 3, 6 and 7 encoding a homologue of heat shock protein 70 and two diverged copies of the coat protein (cpd1 and cpd2), respectively. overall, 75 clones corresponding to orfs 3, 6 and 7 were sequenced and 1916 nucleotide changes were recorded relative to the ... | 2001 | 11597756 |
| complete nucleotide sequence and genome organization of grapevine leafroll-associated virus 3, type member of the genus ampelovirus. | this study reports on the complete genome sequence of grapevine leafroll-associated virus 3, the type member of the genus ampelovirus. the genome is 17 919 nt in size and contains 13 open reading frames (orfs). previously, the sequence of 13 154 nt of the 3'-terminal of the genome was reported. the newly sequenced portion contains a 158 nt 5' utr, a single papain-like protease and a methyltransferase-like (mt) domain. orf1a encodes a large polypeptide with a molecular mass of 245 kda. with a pre ... | 2004 | 15218195 |
| trapping of tomato yellow leaf curl virus (tylcv) and other plant viruses with a groel homologue from the whitefly bemisia tabaci. | to avoid destruction in the haemolymph of their vector, many plant circulative viruses interact with groel homologues produced by insect endosymbiotic bacteria. we have exploited this phenomenon to devise tools allowing trapping of plant viruses by either groel purified from the whitefly bemisia tabaci or by whitefly groel over-expressed in e. coli. pcr tubes or 96-well plates coated with a groel preparation were incubated with cleared sap of virus infected plant leaves or insect vectors. groel- ... | 2004 | 15290375 |
| little cherry virus-2: sequence and genomic organization of an unusual member of the closteroviridae. | the complete genomic sequence of variant usa6b of little cherry virus-2 (lchv-2), has been determined and is 15045 nucleotides in length, coding for 11 open reading frames (orfs). the sequence shares 77.2% identity with a previously published, ca. 6 kb partial replicase sequence of lchv-2 (variant usa6a). both lchv-2/usa6a and lchv-2/usa6b were obtained from the same tree infected with little cherry disease, and would suggest a mixed infection. lchv-2/usa6b is more closely related to the partial ... | 2005 | 15449137 |
| genetic variability and population structure of grapevine leafroll-associated virus 3 isolates. | the genetic variability and population structure of a collection of 45 grapevine leafroll-associated virus 3 (glrav-3) isolates were studied by single-stranded conformation polymorphism (sscp) and sequence analysis of the rna-dependent rna polymerase (rdrp), heat-shock protein 70 homologue (hsp-70) and coat protein (cp) genes. the distribution of sscp profiles was not correlated with the geographical origin of the isolates, indicating that glrav-3 is a single, undifferentiated population. the ma ... | 2005 | 15604449 |
| comparison of three techniques for detection of grapevine leafroll-associated virus 1. | thirty seven plants of grapevine from the research station of viticulture, karlstejn was examined for the presence of leafroll viruses. grapevine leafroll-associated virus 1 (glrav-1) was detected in the grapevines plants tested using double-antibody sandwich elisa (das-elisa), rt-pcr and molecular hybridization with non-radioactive rna probes. both molecular methods were based on a detection of the glrav-1 heat-shock protein 70 (hsp70) gene and showed a higher sensitivity in the detection of gl ... | 2005 | 15929397 |
| genome sequences and structures of two biologically distinct strains of grapevine leafroll-associated virus 2 and sequence analysis. | grapevine leafroll-associated virus 2 (glrav-2), a member of the genus closterovirus within closteroviridae, is implicated in several important diseases of grapevines including "leafroll", "graft-incompatibility", and "quick decline" worldwide. several glrav-2 isolates have been detected from different grapevine genotypes. however, the genomes of these isolates were not sequenced or only partially sequenced. consequently, the relationship of these viral isolates at the molecular level has not be ... | 2005 | 15965606 |
| analysis of the molecular variability of grapevine leafroll-associated virus 1 reveals the presence of two distinct virus groups and their mixed occurrence in grapevines. | genetic diversity of eight grapevine leafroll-associated virus 1 (glrav-1) isolates recovered from grapevines in three distinct locations in the czech republic and slovakia was characterised by restriction fragment length polymorphism (rflp) analysis and by sequencing of cloned 540 bp fragment of the heat shock protein 70 (hsp70) gene. comparison and phylogenetic analysis of obtained and previously available sequence data revealed the existence of two groups of glrav-l isolates, tentatively name ... | 2005 | 16175330 |
| improved detection of grapevine leafroll-associated virus 1 by magnetic capture hybridisation rt-pcr on a conserved region of viral rna. | we report the development of a sensitive diagnostic method for the detection of the grapevine leafroll-associated virus 1 (glrav-1). we have considered the current shortcoming in detection of glrav-1 to be linked to two factors, sequence variation in the viral rna and low template concentration. sequence information available allowed the selection of optimal target sequences for detection by rt-pcr, having high copy number and low levels of sequence variation. this was combined with the use of m ... | 2006 | 16292599 |
| diverse suppressors of rna silencing enhance agroinfection by a viral replicon. | launching the beet yellows virus (byv) minireplicon by agrobacterial delivery resulted in an unexpectedly low number of infected cells per inoculated leaf. this effect was due to a strong rna silencing response in the agroinfiltrated leaves. strikingly, ectopic co-expression of p21, a byv rna silencing suppressor, increased minireplicon infectivity by three orders of magnitude. mutational analysis demonstrated that this effect correlates with suppressor activity of p21. five diverse, heterologou ... | 2006 | 16300814 |
| efficient methods for sample processing and cdna synthesis by rt-pcr for the detection of grapevine viruses and viroids. | template preparation is important in reverse-transcription polymerase chain reaction (rt-pcr)-based detection methods. a tissuelyser with tungsten carbide beads was used for simultaneous processing of up to 48 samples under the same conditions in the development of a simple and rapid procedure to prepare a plant extract for rt reaction. a sandpaper method was also developed by which wood tissue of dormant cuttings could be macerated easily to process with minimal time and effort. it was also dem ... | 2006 | 16510197 |
| the symptomless leaf infection with grapevine leafroll associated virus 3 in grown in vitro plants as a simple model system for investigation of viral effects on photosynthesis. | the photosynthetic changes evaluated by oxygen evolution, chlorophyll fluorescence, photoacoustics, and delayed fluorescence (df) were studied in leaves of grown in vitro for 8 weeks grapevine plants (vitis vinifera) infected by grapevine leafroll-associated virus 3 (glrav-3). the infected leaves were characterized during the viral infection without visible disease symptoms. the symptomless infection led to a decrease in plant biomass. the non-photochemical fluorescence quenching, qn, declined, ... | 2007 | 16716452 |
| antiviral activity of tiazofurin and mycophenolic acid against grapevine leafroll-associated virus 3 in vitis vinifera explants. | the ability to control plant viral diseases with chemicals has great potential value for agriculture, but few chemicals are available to date due to the difficulty in obtaining effective drugs. imp dehydrogenase is an enzyme which catalyzes the conversion of inosine 5'-monophosphate to xanthosine 5'-monophosphate in the de novo purine nucleotide synthetic pathway, and is considered a sensitive target for antiviral drugs. two impdh inhibitors, tiazofurin (tr) and mycophenolic acid (mpa), were tes ... | 2007 | 17125850 |
| molecular analysis of double-stranded rnas reveals complex infection of grapevines with multiple viruses. | the table grape variety "waltham cross" was infected with leafroll and shiraz disease. to reveal specific viruses that are associated with the diseased plants, we used an rt-pcr-based strategy to determine partial genome sequences of these viruses. upon cloning and sequencing of the rt-pcr products, we detected seven groups of viral variants that are related to four species of the closteroviridae: grapevine leafroll-associated virus 1, 2, 3, and 5, in addition to rupestris stem pitting-associate ... | 2007 | 17129630 |
| a sensitive one-step real-time rt-pcr method for detecting grapevine leafroll-associated virus 2 variants in grapevine. | grapevine leafroll syndrome is caused by a complex of up to nine different grapevine leafroll-associated viruses (glrav-1-9) with glrav-2 being reported as one of the most variable species of this group. many methods, including indexing, serological and molecular procedures, have been developed for the detection of glrav-2. however, due to the low concentration of the virus in plants and the high variability of glrav-2, a method with improved sensitivity and with the capacity to detect of all kn ... | 2007 | 17223202 |
| senescence-associated genes induced during compatible viral interactions with grapevine and arabidopsis. | the senescence process is the last stage in leaf development and is characterized by dramatic changes in cellular metabolism and the degeneration of cellular structures. several reports of senescence-associated genes (sags) have appeared, and an overlap in some of the genes induced during senescence and pathogen infections has been observed. for example, the enhanced expression of sags in response to diseases caused by fungi, bacteria, and viruses that trigger the hypersensitive response (hr) or ... | 2007 | 17761729 |
| resistance to grapevine leafroll associated virus-2 is conferred by post-transcriptional gene silencing in transgenic nicotiana benthamiana. | grapevine leafroll-associated virus-2 (glrav-2) is an important component of the leafroll disease complex in grapevine. we have previously sequenced the glrav-2 genome and identified the coat protein (cp) gene. the objective of this study is to test the concept of pathogen-derived resistance against a closterovirus associated with grapevine leafroll disease. because glrav-2 is capable of infecting nicotiana benthamiana, we decided to test the concept on this herbaceous host. thirty-seven t(0) tr ... | 2008 | 17912600 |
| complete nucleotide sequence of a south african isolate of grapevine leafroll-associated virus 3 reveals a 5'utr of 737 nucleotides. | | 2008 | 18274697 |
| complete nucleotide sequence and genome organization of pineapple mealybug wilt-associated virus-1. | pineapple mealybug wilt-associated virus-1 (pmwav-1; family closteroviridae, genus ampelovirus) belongs to a complex of mealybug-transmissible viruses found in pineapple worldwide. in this study, the complete genome of pmwav-1 was sequenced and found to be 13.1 kb in length, making it the smallest in the family. the genome encoded seven open reading frames (orfs) and was unusual for an ampelovirus due to the lack of an intergenic region between the rdrp and p6 orfs, an orf encoding a relatively ... | 2008 | 18283409 |
| comparison of low-density arrays, rt-pcr and real-time taqman rt-pcr in detection of grapevine viruses. | low-density arrays (lda) have been designed based on the real-time rt-pcr (taqman) assays for the specific detection of 13 viruses that infect grapevines in addition to the housekeeping gene 18s rrna. the viruses included in the study are grapevine leafroll associated viruses 1, 2, 3, 4, 5, and 9, grapevine leafroll associated virus-2 redglobe (glrav-2rg) strain, ruspestris stem pitting associated virus, grapevine vitivirus a, grapevine vitivirus b, grapevine fanleaf virus, tomato ringspot virus ... | 2008 | 18329731 |
| generation and characterization of a recombinant antibody fragment that binds to the coat protein of grapevine leafroll-associated virus 3. | pathogen-specific recombinant antibodies have been used to characterize pathogen infections and to engineer resistance in crops. we selected a single-chain antibody fragment (scfvlr3cp-1) specific for the coat protein of grapevine leafroll-associated virus 3 (glrav-3), one of the agents of grapevine leafroll (glr) disease, from a phage display library. the antibody binds specifically to the entire length of glrav-3 particles and has a high binding affinity value (k(d)) of 42 nm. the amino acid m ... | 2008 | 18478181 |
| genome analysis and detection of a chilean isolate of grapevine leafroll associated virus-3. | the complete genome of the chilean isolate cl-766 of grapevine leafroll-associated virus-3 (glrav-3) has been sequenced. this is the first genome sequence obtained from a glrav-3 isolate of the southern hemisphere. the genomic rna of 17,919 nucleotides contains 13 open reading frames (orfs) with 5' and 3' untranslated regions (utr) of 158 and 277 nucleotides, respectively. comparison with ny1, the only isolate with complete genomic sequence available today, shows 97.6% nucleotide identity betwee ... | 2008 | 18498048 |
| detection and partial characterization of a second closterovirus associated with little cherry disease, little cherry virus-2. | abstract little cherry disease (lchd) is a complex and serious viral disease of cherry. although originally described almost 70 years ago, there has been little progress in identifying the causal agent of the disease due to the difficulty in obtaining purified virus from infected trees. this problem was partially overcome in 1997 when the compete sequence of a closterovirus associated with lchd, little cherry virus (lchv), was published. this virus could be associated with some, but not all, tre ... | 2001 | 18943345 |
| partial characterization of a closterovirus associated with apple mealybug-transmitted little cherry disease in north america. | abstract little cherry disease (lchd) is a serious economic problem of sweet cherry production in western north america where apple mealybug is the principle vector. lchd is associated with a distinct species of double-stranded (ds) rna. in this study, filamentous virus particles were purified from lchd-infected trees and shown to contain single-stranded rna corresponding to the previously reported dsrna isolated from infected trees. the virus particles were characterized and were similar to mon ... | 2001 | 18943346 |
| partial genome organization, identification of the coat protein gene, and detection of grapevine leafroll-associated virus-5. | abstract the genome of grapevine leafroll-associated virus-5 (glrav-5) was cloned, and the sequence of 4766 nt was determined. degenerate oligonucleotide primers designed from the conserved closterovirus heat shock 70 protein (hsp 70) homologue were used to obtain viral-specific sequences to anchor the cloning of the viral rna with a genomic walking approach. the partial nucleotide (nt) sequence of glrav-5 showed the presence of four open reading frames (orf a through d), potentially coding for ... | 2001 | 18943347 |
| transmission of grapevine leafroll-associated virus 3 by the vine mealybug (planococcus ficus). | grapevine leafroll disease is caused by grapevine leafroll-associated viruses (glravs). within this virus complex, glrav-3 is the predominant species in the world. several glravs have been shown to be transmitted from vine to vine by mealybugs although a detailed characterization of transmission biology is lacking. the introduction of the vine mealybug (planococcus ficus) in california and other regions of the world may result in increasing disease incidence of established glravs. we studied the ... | 2008 | 18943455 |
| simultaneous detection of nine grapevine viruses by multiplex reverse transcription-polymerase chain reaction with coamplification of a plant rna as internal control. | abstract a multiplex reverse transcription-polymerase chain reaction (mrt-pcr) was developed for simultaneous detection of nine grapevine viruses: arabis mosaic virus, grapevine fanleaf virus, grapevine virus a, grapevine virus b, rupestris stem pitting-associated virus, grapevine fleck virus, grapevine leafroll-associated virus-1, -2, and -3, in combination with a plant rna internal control used as an indicator of the effectiveness of rna extraction and rt-pcr. primers were designed from conser ... | 2006 | 18943959 |
| tandem leader proteases of grapevine leafroll-associated virus-2: host-specific functions in the infection cycle. | several viruses in the genus closterovirus including grapevine leafroll-associated virus-2 (glrav-2), encode a tandem of papain-like leader proteases (l1 and l2) whose functional profiles remained largely uncharacterized. we generated a series of the full-length, reporter-tagged, clones of glrav-2 and demonstrated that they are systemically infectious upon agroinfection of an experimental host plant nicotiana benthamiana. these clones and corresponding minireplicon derivatives were used to addre ... | 2009 | 19007962 |
| an assay for the detection of grapevine leafroll-associated virus 3 using a single-chain fragment variable antibody. | grapevine leafroll-associated virus 3 (glrav-3) is a major pathogen of grapevine. a previously described single-chain fragment variable (scfv) antibody (scfvlr3), directed against the coat protein (cp) of glrav-3, was expressed in escherichia coli and used to develop a diagnostic elisa kit. the antibody was fused to the light chain constant domain of human immunoglobulin to create the bivalent reagent c(l)-lr3, which was purified from the periplasmic fraction, giving a yield of ~5 mg/l. the sens ... | 2009 | 19082687 |
| diversity of ampeloviruses in mealybug and soft scale vectors and in grapevine hosts from leafroll-affected vineyards. | the occurrence and diversity of grapevine leafroll-associated virus 1 (glrav-1) and grapevine leafroll-associated virus 3 (glrav-3) in the soft scales parthenolecanium corni and pulvinaria innumerabilis and in the mealybug pseudococcus maritimus was determined in leafroll-affected vineyards in the finger lakes region of new york. groups of 1 to 4 specimens were collected under loose grapevine bark and tested by reverse-transcription polymerase chain reaction (rt-pcr) for segments of the second d ... | 2009 | 19740031 |
| a diagnostic oligonucleotide microarray for simultaneous detection of grapevine viruses. | at least 58 viruses have been reported to infect grapevines causing economic damage globally. conventional detection strategies based on serological assays, biological indexing and rt-pcr targeting one or few viruses in each assay are widely used. grapevines are prone to contain mixed infections of several viruses, making the use of these techniques time-consuming. a 70-mer oligonucleotide microarray able to detect simultaneously a broad spectrum of known viruses as well as new viruses by cross- ... | 2010 | 19914293 |
| analysis of multiple virus-infected grapevine plant reveals persistence but uneven virus distribution. | ln33 grapevine plants were artificially inoculated with budwoods originating from a field-cultivated traminer grapevine which was naturally infected with grapevine leafroll-associated virus 1 (glrav-1), grapevine virus a (gva), grapevine virus b (gvb), rupestris stem pitting-associated virus (rspav), and an unclassified tymovirus. four years after inoculation, a comparison of the cane weights between healthy and infected grapevines did not show any significant difference. corky bark symptoms or ... | 2009 | 19941393 |
| deep sequencing analysis of viruses infecting grapevines: virome of a vineyard. | double stranded rna, isolated from 44 pooled randomly selected vines from a diseased south african vineyard, has been used in a deep sequencing analysis to build a census of the viral population. the dsrna was sequenced in an unbiased manner using the sequencing-by-synthesis technology offered by the illumina genome analyzer ii and yielded 837 megabases of metagenomic sequence data. four known viral pathogens were identified. it was found that grapevine leafroll-associated virus 3 (glrav-3) is t ... | 2010 | 20172578 |
| genetic variability of natural populations of grapevine leafroll-associated virus 2 in pacific northwest vineyards. | genetic variability of field populations of grapevine leafroll-associated virus 2 (glrav-2) in pacific northwest (pnw) vineyards was characterized by sequencing the entire coat protein (cp) and a portion of the heat-shock protein-70 homolog (hsp70h) genes. phylogenetic analysis of cp and hsp70h nucleotide sequences obtained in this study and corresponding sequences from genbank revealed segregation of glrav-2 isolates into six lineages with virus isolates from pnw distributed in 'pn', 'h4', and ... | 2010 | 20528188 |
| mapping of the 5' terminal nucleotides of grapevine leafroll-associated virus 3 sgrnas. | grapevine leafroll-associated virus 3 (glrav-3) is a positive sense, single stranded rna virus that has a detrimental effect on wine and table grapes worldwide. previous studies have shown that glrav-3, like other closteroviruses produces subgenomic (sg) rnas during replication and that these sgrnas are deployed for the expression of the orfs on the 3' half of the genome. in this study a dsrna blot confirmed the presence of three, 3' co-terminal sgrnas species [sgrna(orf3/4), sgrna(orf5) and sgr ... | 2010 | 20561952 |
| citrus mealybug (hemiptera: pseudococcidae) movement and population dynamics in an arbor-trained vineyard. | the citrus mealybug, planococcus citri (risso) (hemiptera: pseudococcidae), is the main grapevine pest in vineyards in some countries, such as spain and brazil. in galician vineyards (northwestern spain), mealybug population levels are low because the accumulated degree-days are lower than in other grapevine-growing areas. the main problem caused by mealybugs is the transmission of viruses, even at low infestation levels. the active period of citrus mealybug in the study vineyard lasted from jul ... | 2010 | 20568606 |
| mealybug transmission of grapevine leafroll viruses: an analysis of virus-vector specificity. | to understand ecological factors mediating the spread of insect-borne plant pathogens, vector species for these pathogens need to be identified. grapevine leafroll disease is caused by a complex of phylogenetically related closteroviruses, some of which are transmitted by insect vectors; however, the specificities of these complex virus-vector interactions are poorly understood thus far. through biological assays and phylogenetic analyses, we studied the role of vector-pathogen specificity in th ... | 2010 | 20626287 |
| 3'-coterminal subgenomic rnas and putative cis-acting elements of grapevine leafroll-associated virus 3 reveals 'unique' features of gene expression strategy in the genus ampelovirus. | the family closteroviridae comprises genera with monopartite genomes, closterovirus and ampelovirus, and with bipartite and tripartite genomes, crinivirus. by contrast to closteroviruses in the genera closterovirus and crinivirus, much less is known about the molecular biology of viruses in the genus ampelovirus, although they cause serious diseases in agriculturally important perennial crops like grapevines, pineapple, cherries and plums. | 2010 | 20682046 |
| the complete genome sequence of the bd variant of grapevine leafroll-associated virus 2. | | 2010 | 20694566 |
| modulation of flavonoid biosynthetic pathway genes and anthocyanins due to virus infection in grapevine (vitis vinifera l.) leaves. | symptoms of grapevine leafroll disease (glrd) in red-fruited wine grape (vitis vinifera l.) cultivars consist of green veins and red and reddish-purple discoloration of inter-veinal areas of leaves. the reddish-purple color of symptomatic leaves may be due to the accumulation of anthocyanins and could reflect an up-regulation of genes involved in their biosynthesis. | 2010 | 20731850 |
| three genetic grapevine leafroll-associated virus 3 variants identified from south african vineyards show high variability in their 5'utr. | three genetic variants of grapevine leafroll-associated virus 3 (glrav-3) were identified in vineyards of the western cape, south africa. the glrav-3 variants were identified by single-strand conformation polymorphism (sscp) profiles generated from a region amplified in orf5. orf5 sequence data confirmed the three genetic variant groups, and a specific sscp profile was assigned to each variant group. the results of sscp analysis of this region in orf5 showed that this method gives a fast and rel ... | 2010 | 20830600 |
| five phylogenetic groups identified in the coat protein gene of grapevine leafroll-associated virus 3 obtained from portuguese grapevine varieties. | the genetic variability and population structure of grapevine leafroll-associated virus 3 (glrav-3) variants were updated by examining the diversity within the viral coat protein (cp) gene among 174 isolates belonging to a collection of vitis vinifera representing most of the portuguese varieties. phylogenetic analysis revealed the existence of five well-defined clusters. three of these correspond to previously defined groups, another corresponds to variants from chile for which only one sequenc ... | 2010 | 21153745 |
| quantitation of grapevine leafroll associated virus-1 and -3, grapevine virus a, grapevine fanleaf virus and grapevine fleck virus in field-collected vitis vinifera l. 'nebbiolo' by real-time reverse transcription-pcr. | taqman one-step real-time qrt-pcr assays were developed for the quantitation of grapevine leafroll associated virus-1 and -3 (glrav-1 and -3), grapevine virus a (gva), grapevine fanleaf virus (gflv) and grapevine fleck virus (gfkv) in vitis vinifera l. virus load in the progenies of three 'nebbiolo' clones planted in two experimental vineyards in piemonte (northwestern italy), and carrying the viruses in different combinations, was evaluated. quantitation primers were designed on the rna-depende ... | 2010 | 21167205 |
| genome-wide analysis of the set domain group family in grapevine. | the set domain group (sdg) proteins represent an evolutionarily-conserved family of epigenetic regulators present in eukaryotes and are putative candidates for the catalysis of lysine methylation in histones. plant genomes analyses of this family have been performed in arabidopsis, maize, and rice and functional studies have shown that sdg genes are involved in the control of plant development. in this work, we describe the identification and structural characterization of sdg genes in the vitis ... | 2011 | 21293861 |
| genetic diversity in the 3' terminal 4.7-kb region of grapevine leafroll-associated virus 3. | grapevine leafroll-associated virus 3 (glrav-3; ampelovirus, closteroviridae), associated with grapevine leafroll disease, is an important pathogen found across all major grape-growing regions of the world. the genetic diversity of glrav-3 in napa valley, ca, was studied by sequencing 4.7 kb in the 3' terminal region of 50 isolates obtained from vitis vinifera 'merlot'. glrav-3 isolates were subdivided into four distinct phylogenetic clades. no evidence of positive selection was observed in the ... | 2011 | 21391825 |
| biological, molecular, and serological studies of a novel strain of grapevine leafroll-associated virus 2. | in california, a novel closterovirus was detected in "redglobe" grapevine, associated with graft incompatibility and given a trivial name "grapevine rootstock stem lesion associated virus (grslav)." the biological properties of the putative virus were ascertained when asymptomatic yet infected redglobe scion buds were graft-inoculated onto test plants of cabernet sauvignon propagated on 18 different rootstocks. it proved lethal on test plants growing on rootstocks 1616c, 5bb, 5c, 3309c, and 1103 ... | 2011 | 21487783 |
| grapevine leafroll-associated virus 1 occurs as genetically diverse populations. | the genetic diversity of thirty-four isolates of grapevine leafroll-associated virus 1 (glrav-1) from different wine, table and ornamental grape cultivars in california, new york and washington states in the u.s.a. was investigated. segments of the heat-shock protein 70 homolog (hsp70h) gene, coat protein (cp) gene, coat protein duplicate 2 (cpd2) gene and orf9 (p24) were amplified by rt-pcr, cloned and sequenced. a pairwise comparison of nucleotide sequences revealed intra- and inter-isolate se ... | 2011 | 21830956 |
| occurrence of grapevine leafroll-associated virus complex in napa valley. | grapevine leafroll disease (gld) is caused by a complex of several virus species (grapevine leafroll-associated viruses, glrav) in the family closteroviridae. because of its increasing importance, it is critical to determine which species of glrav is predominant in each region where this disease is occurring. a structured sampling design, utilizing a combination of rt-pcr based testing and sequencing methods, was used to survey glravs in napa valley (california, usa) vineyards (n = 36). of the 2 ... | 2011 | 22039446 |
| a multidisciplinary study on the effects of phloem-limited viruses on the agronomical performance and berry quality of vitis vinifera cv. nebbiolo. | viral infections are known to have a detrimental effect on grapevine yield and performance, but there is still a lack of knowledge about their effect on the quality and safety of end products. vines of vitis vinifera cv. nebbiolo clone 308, affected simultaneously by grapevine leafroll-associated virus 1 (glrav-1), grapevine virus a (gva), and rupestris stem pitting associated virus (rspav), were subjected to integrated analyses of agronomical performance, grape berry characteristics, instrument ... | 2011 | 21856458 |
| genomic analysis of grapevine leafroll associated virus-5 and related viruses. | the grapevine leafroll-associated viruses (glravs) (closteroviridae) represent an emerging threat to world grape production. one group of glravs within the genus ampelovirus, the glrav-4-like viruses (glrav-4lvs), contains a fragmented collection of seven viruses only two of which (glrav-pr and glracv) are fully sequenced. here in reporting the sequence of glrav-5, a member of glrav-4lvs, we identify genomic elements common to the glrav-4lv group. exclusive properties include a highly conserved ... | 2011 | 21893115 |
| Molecular and histological characterisation of primary (ß-proteobacteria) and secondary (?-proteobacteria) endosymbionts of three species of mealybugs (Pseudococcus longispinus, Pseudococcus calceolariae, Pseudococcus viburni) (Pseudococcidae, Hemiptera) and prediction of interactions of their GroEL homologs with Grape Leaf Roll-associated Virus-3. | Microscopic localization of endosymbiotic bacteria in three species of mealybug (Pseudococcus longispinus, long-tailed mealybug; Pseudococcus calceolariae, citrophilus mealybug; and Pseudococcus. viburni, obscure mealybug) showed these organisms were confined to bacteriocyte cells within a bacteriome centrally located within the haemocoel. Two species of bacteria were present, with the secondary endosymbiont, in all cases, living within the primary endosymbiont. DNA from the dissected bacteriome ... | 2011 | 22156418 |
| genomic and biological analysis of grapevine leafroll-associated virus 7 reveals a possible new genus within the family closteroviridae. | deep sequencing analysis of an asymptomatic grapevine revealed a virome containing five rna viruses and a viroid. of these, grapevine leafroll-associated virus 7 (glrav-7), an unassigned closterovirus, was by far the most prominently represented sequence in the analysis. graft-inoculation of the infection to another grape variety confirmed the lack of the leafroll disease symptoms, even though glrav-7 could be detected in the inoculated indicator plants. a 16,496 nucleotide-long genomic sequence ... | 2011 | 22056321 |
| molecular characterization and taxonomy of grapevine leafroll-associated virus 7. | the complete nucleotide sequence of an albanian isolate of grapevine leafroll-associated virus 7 (glrav-7-alb) was determined. the viral genome consists of 16,404 nucleotides and has nine open reading frames (orfs) that potentially encode proteins, most of which are typical for members of the family closteroviridae. only the 25-kda (orf8) and 27-kda (orf9) proteins had no apparent similarity to other viral proteins in the sequence databases. the genome structure of glrav-7-alb closely resembles ... | 2011 | 22109709 |
| effect of host plant tissue on the vector transmission of grapevine leafroll-associated virus 3. | many biotic and abiotic factors affect the transmission efficiency of vector-borne plant pathogens. insect vector within-plant distribution and host tissue preference are known to affect pathogen acquisition and inoculation rates. in this study, we first investigated whether feeding tissue affects the transmission of grapevine leafroll-associated virus 3 by planococcus ficus (signoret) (hemiptera: pseudococcidae) and the effect of mealybug within-plant distribution on virus transmission under gr ... | 2011 | 22066175 |
| comparative detection of a large population of grapevine viruses by taqman(®) rt-qpcr and elisa. | grapevine (vitis spp.) can be infected by numerous viruses that are often widespread and of great economic importance. reliable detection methods are necessary for sanitary selection which is the only way to partly control grapevine virus diseases. biological indexing and elisa are currently the standard methods for screening propagation material, and pcr-methods are becoming increasingly popular. due to the diversity of virus isolates, it is essential to verify that the tests allow the detectio ... | 2017 | 27923589 |
| multiplex rt-pcr method for the simultaneous detection of nine grapevine viruses. | viral diseases are a serious pathological problem for grapevines, and in recent years the need for increasingly specific and rapid diagnostic methods for the selection of propagation materials has grown. arabis mosaic virus, grapevine fanleaf virus, grapevine virus a, grapevine virus b, grapevine rupestris stem pitting-associated virus, grapevine fleck virus, and grapevine leafroll-associated viruses 1, 2, and 3 are nine of the most widespread viruses that naturally infect grapevines. a multiple ... | 2015 | 25287494 |
| real-time multiplex rt-pcr for the simultaneous detection of the five main grapevine viruses. | a real-time multiplex rt-pcr has been developed for the simultaneous detection and identification of the major rna viruses that infect grapevines (grapevine fanleaf virus, arabis mosaic virus, grapevine leafroll-associated virus 1, grapevine leafroll-associated virus 3 and grapevine fleck virus). serial dilutions of infected plant extracts were tested using the new method, and the results were compared with those obtained using a commercially available elisa and real-time singleplex rt-pcr. the ... | 2013 | 23219809 |
| the closterovirus-derived gene expression and rna interference vectors as tools for research and plant biotechnology. | important progress in understanding replication, interactions with host plants, and evolution of closteroviruses enabled engineering of several vectors for gene expression and virus-induced gene silencing. due to the broad host range of closteroviruses, these vectors expanded vector applicability to include important woody plants such as citrus and grapevine. furthermore, large closterovirus genomes offer genetic capacity and stability unrivaled by other plant viral vectors. these features provi ... | 2013 | 23596441 |
| detection and molecular characterization of egyptian isolates of grapevine viruses. | selected commercial and/or local vineyards and nurseries in three different governorates of egypt (alexandria, el-beheira and el-menofia) were surveyed for symptoms indicative of infection by grapevine viruses. leaf samples from red-fruited and white-fruited vitis vinefera were tested for grapevine leafroll associated viruses (glrav-1, glrav-2, and glrav-3), grapevine viruses a and b (gva, gvb), grapevine rupestris stem pitting virus (grspav), grapevine fanleaf virus (gflv), and grapevine fleck ... | 2014 | 24957718 |
| evidence of grapevine leafroll associated virus-1-3, grapevine fleck virus and grapevine virus b occurring in himachal pradesh, india. | during a survey conducted in the grapevine orchards of himachal pradesh, variety of symptoms ranging from leaf yellowing, vein greening, reduced leaf size, downward rolling/cup shaped leaves to reduced fruit bearing were observed. symptomatic leaf samples were collected and analyzed by serological (das-elisa) and molecular methods (rt-pcr, pcr) for viruses and phytoplasma known worldwide on grapevine. das-elisa was used for detection of grapevine leafroll associated virus 1, 2 and 3 (glrav-1, 2 ... | 2013 | 24426260 |
| ferrisia gilli (hemiptera: pseudococcidae) transmits grapevine leafroll-associated viruses. | several mealybug species are vectors of grapevine leafroll-associated viruses (glrav), which cause the economically important grapevine leafroll disease in grape-producing regions worldwide. the mealybug ferrisia gilli gullan is a new pest of grapevines in el dorado county, located in the sierra foothill wine-growing region of california. glrav species 1, 2, 3, and 4lv have been detected in vineyards with symptomatic vines in the sierra foothills. we conducted controlled virus acquisition and tr ... | 2016 | 27329635 |
| transmission of grapevine virus a and grapevine leafroll-associated virus 1 and 3 by heliococcus bohemicus (hemiptera: pseudococcidae) nymphs from plants with mixed infections. | mealybugs (hemiptera: pseudococcidae) represent a serious threat for viticulture as vectors of phloem-restricted viruses associated with the grapevine rugose wood and leafroll diseases. heliococcus bohemicus (šulc) is known to be involved in the spread of these two viral diseases, being a vector of the grapevine virus a (gva) and the grapevine leafroll-associated virus 1 and 3 (glrav-1 and glrav-3). this study investigated the acquisition and transmission efficiency of h. bohemicus fed on mixed- ... | 2016 | 27329628 |
| molecular characterization of a novel putative ampelovirus tentatively named grapevine leafroll-associated virus 13. | a novel putative ampelovirus was detected in grapevines that showed typical leafroll symptoms and was tentatively named grapevine leafroll-associated virus (glrav)-13 following the series of numbering of other glravs. the complete genome of glrav-13 comprised 17,608 nt and contained eleven putative open reading frames, showing genetic features similar to those of viruses belonging to subgroup i of genus ampelovirus. phylogenetic trees based on the rna-dependent rna polymerase, heat shock protein ... | 2016 | 27289224 |
| slowing the spread of grapevine leafroll-associated viruses in commercial vineyards with insecticide control of the vector, pseudococcus maritimus (hemiptera: pseudococcidae). | vineyards were surveyed for grapevine leafroll-associated viruses and their insect vectors in new york state's finger lakes region in 2006-2008. grape mealybug, pseudococcus maritimus (erhorn) (hemiptera: pseudococcidae), european fruit lecanium, parthenolecanium corni (bouche), and cottony maple scale, pulvinaria acericola (walsh and riley) (hemiptera: coccidae) were identified as vector species in this region. an increase in the incidence of grapevine leafroll-associated virus 1 (glrav-1) and ... | 2015 | 26223949 |
| genetic diversity and recombination analysis of grapevine leafroll-associated virus 1 from china. | grapevine leafroll-associated virus 1 (glrav-1) is one of the causal agents of grapevine leafroll disease (gld). to investigate the prevalence and genetic variation of glrav-1 in china, 132 grapevine samples from 14 chinese provinces and regions were tested using reverse transcription pcr (rt-pcr) and reverse transcription nested pcr (rt-npcr). the samples included symptomatic and asymptomatic cultivars, and 36.4% of them tested positive for glrav-1. 'beida' samples, previously identified as vir ... | 2015 | 25925705 |
| molecular data mining to improve antibody-based detection of grapevine leafroll-associated virus 1 (glrav-1). | testing for grapevine leafroll-associated virus 1 (glrav-1) is mandatory in certification schemes of propagation material within the eu. accurate and reliable diagnostic assays are necessary for implementation of this measure. during routine detection of glrav-1, using double antibody sandwich enzyme-linked immunosorbent assay (das-elisa) and reverse transcription (rt) followed by polymerase chain reaction (pcr), evidence was obtained that positive samples could be overlooked by either or both d ... | 2013 | 24056263 |
| analysis of a short genomic region of grapevine leafroll-associated virus 1 (glrav-1) reveals the presence of two different molecular groups of isolates in slovakia. | although grapevine leafroll-associated virus 1 (glrav-1) is one of the most important agents of the grapevine leafroll disease, the data about its molecular variability are scarce. in order to assess the glrav-1 diversity in slovakia, the sequence of a genome region encoding the central part of the capsid protein (cp) gene was determined from 18 glrav-1 isolates. despite the fact that the analysis targeted a relatively short portion of the genome, comparison of obtained sequences has revealed th ... | 2013 | 24020761 |
| macroarray detection of grapevine leafroll-associated viruses. | grapevine leafroll-associated viruses (glravs) are an emerging group of viruses that represent a significant threat to the global productivity and sustainability of the grapevine industry. their control is achieved through the identification and elimination of infected vines, and the use of planting material derived from virus-tested, certified stocks. as such, much effort has been invested in developing reliable molecular diagnostic techniques. in this work, we report the development of a macro ... | 2012 | 22580028 |
| transmission of six ampeloviruses and two vitiviruses to grapevine by phenacoccus aceris. | grapevine leafroll disease is caused by grapevine leafroll-associated viruses (glravs). these viruses are common in vineyards worldwide and often associated with vitiviruses that are involved in the rugose wood complex of grapevine. ten mealybug species are known as vectors of one or several of these grapevine viruses, including the apple mealybug phenacoccus aceris which is widespread in holarctic regions and able to transmit grapevine leafroll-associated virus-1 and -3 (glrav-1 and -3). our ai ... | 2012 | 22439861 |
| efficient transient expression of recombinant proteins in plants by the novel peff vector based on the genome of potato virus x. | agroinfiltration of plant leaves with binary vectors carrying a gene of interest within a plant viral vector is a rapid and efficient method for protein production in plants. previously, we constructed a self-replicating vector, pa7248amv, based on the genetic elements of potato virus x (pvx), and have shown that this vector can be used for the expression of recombinant proteins in nicotiana benthamiana. however, this vector is almost 18 kb long and therefore not convenient for genetic manipulat ... | 2017 | 28293244 |
| characterization of silencing suppressor p24 of grapevine leafroll-associated virus 2. | grapevine leafroll-associated virus 2 (glrav-2) p24 has been reported to be an rna silencing suppressor (rss). however, the mechanisms underlying p24's suppression of rna silencing are unknown. using agrobacterium infiltration-mediated rna silencing assays, we showed that glrav-2 p24 is a strong rss triggered by positive-sense green fluorescent protein (gfp) rna, and that silencing suppression by p24 effectively blocks the accumulation of small interfering rnas. deletion analyses showed that the ... | 2016 | 27997767 |
| critical regions and residues for self-interaction of grapevine leafroll-associated virus 2 protein p24. | the 24-kda protein (p24) encoded by grapevine leafroll-associated virus 2 (glrav-2) is an rna-silencing suppressor. in this work, a yeast two-hybrid system (yths) and bimolecular fluorescence complementation analyses showed that glrav-2 p24 can interact with itself, and that this interaction occurs in the cytoplasm of nicotiana benthamiana cells. to identify the functional region(s) and crucial amino acid residues required for p24 self-interaction, various truncated and substitution mutants were ... | 2016 | 27084306 |
| molecular characterization and impacts of a strain of grapevine leafroll-associated virus 2 causing asymptomatic infection in a wine grape cultivar. | grapevine leafroll (gld) is considered as the most economically important virus disease affecting wine grapes (vitis vinifera l.) in many grapevine-growing regions. gld produces distinct symptoms in red- and white-berried cultivars. in this study, we determined the complete genome sequence of an asymptomatic strain of grapevine leafroll-associated virus 2 (glrav-2) and studied its impacts on fruit yield and berry quality attributes in an own-rooted, red-berried wine grape cultivar. | 2013 | 24171725 |
| association of a dna virus with grapevines affected by red blotch disease in california. | in the napa valley of california, vineyards of 'cabernet franc' (cf) clone 214, 'cabernet sauvignon' clone 337, and 'zinfandel' clone 1a (z1a) with grapevines exhibiting foliar symptoms of red blotches, marginal reddening, and red veins that were accompanied by reduced sugar accumulation in fruit at harvest were initially suspected to be infected with leafroll-associated viruses. however, reverse-transcription polymerase chain reaction (pcr) tests were negative for all known leafroll-associated ... | 2013 | 23656312 |
| combined effect of virus infection and water stress on water flow and water economy in grapevines. | water limitation is one of the major threats affecting grapevine production. thus, improving water-use efficiency (wue) is crucial for a sustainable viticulture industry in mediterranean regions. under field conditions, water stress (ws) is often combined with viral infections as those are present in major grape-growing areas worldwide. grapevine leafroll-associated virus 3 (glrav-3) is one of the most important viruses affecting grapevines. indeed, the optimization of water use in a real contex ... | 2017 | 28044321 |
| differential expression of mirnas and associated gene targets in grapevine leafroll-associated virus 3-infected plants. | micrornas (mirnas) are a class of endogenous small non-coding rnas (srna) that play an essential role in the regulation of target mrnas expressed during plant development and in response to stress. microrna expression profiling has helped to identify mirnas that regulate a range of processes, including the plant's defence response to pathogens. in this study, differential mirna expression in own-rooted vitis vinifera cv. cabernet sauvignon plants infected with grapevine leafroll-associated virus ... | 2017 | 28025711 |
| a synoptic analysis of the temporal and spatial aspects of grapevine leafroll disease in a historic napa vineyard and experimental vine blocks. | five grapevine leafroll-associated virus 3 (glrav-3) epidemics were analyzed utilizing a standardized approach to robustly characterize the temporal and spatial parameters. published data included in the analysis are from spain, new zealand, and napa valley, ca together with new data from a historic vineyard in napa valley, ca. linear regression analyses of logit-transformed incidence data indicated a maximum average increase of 11% per year in disease incidence, with considerable variation amon ... | 2017 | 27938242 |
| harbin: a quantitation pcr analysis tool. | to enable analysis and comparisons of different relative quantitation experiments, a web-browser application called harbin was created that uses a quantile-based scoring system for the comparison of samples at different time points and between experiments. | 2017 | 27695982 |
| responses of in vitro-grown plantlets (vitis vinifera) to grapevine leafroll-associated virus-3 and peg-induced drought stress. | stresses caused by viral diseases and drought have long threatened sustainable production of grapevine. these two stresses frequently occur simultaneously in many of grapevine growing regions of the world. we studied responses of in vitro-grown plantlets (vitis vinifera) to grapevine leafroll associated virus-3 (glrav-3) and peg-induced drought stress. results showed that stress induced by either virus infection or drought had negative effects on vegetative growth, caused significant decreases a ... | 2016 | 27313542 |
| molecular characterization of a grapevine leafroll-associated virus 4 from slovenian vineyards. | during a survey conducted in vineyards in slovenia, variety of grapevine leafroll disease symptoms were observed. mixed infection with grapevine leafroll-associated viruses 3 and 4 (glrav-3, -4) in two grapevines from a vineyard in south-western part of slovenia was confirmed by das-elisa in 2010. the 3'final 1769 nucleotides of the slovenian glrav-4 isolate were assembled from amplicons obtained by ic rt-pcr. the complete coat protein (cp) and p23 gene sequences were compared with other glrav-4 ... | 2016 | 27265467 |
| sybr(®) green-based real-time quantitative reverse-transcription pcr for detection and discrimination of grapevine viruses. | a sybr(®) green-based real-time quantitative reverse transcription pcr (qrt-pcr) assay in combination with melt-curve analysis (mca) was optimized for the detection of nine grapevine viruses. the detection limits for simplex qrt-pcr for all nine grapevine viruses were estimated to be in the range of 214-1112 copies of the virus genome. amplicons with melting temperatures (tm) separated by at least 2°c in the mca could differentiate two viruses in the same reaction. therefore, eight of the nine v ... | 2016 | 27246908 |
| interactive effects of grapevine leafroll-associated virus 3 (glrav-3) and water stress on the physiology of vitis vinifera l. cv. malvasia de banyalbufar and giro-ros. | among several biotic and abiotic stress combinations, interaction between drought and pathogen is one of the most studied combinations in some crops but still not in grapevine. in the present work, we focused on the interaction effects of biotic (glrav-3) and abiotic (drought) stresses on grapevine photosynthetic metabolism on two cultivars (cvs. 'malvasia de banyalbufar and giro-ros'). non-infected and glrav-3 infected potted plants were compared under water stress conditions (ws) and well-wate ... | 2016 | 27153513 |
| alterations in primary and secondary metabolism in vitis vinifera 'malvasía de banyalbufar' upon infection with grapevine leafroll-associated virus 3. | plant defense mechanisms against pathogens result in differential regulation of various processes of primary and secondary metabolism. imaging techniques, such as fluorescence imaging and thermography, are very valuable tools providing spatial and temporal information about these processes. in this study, effects of grapevine leafroll-associated virus 3 (glrav-3) on grapevine physiology were analyzed in pot-grown asymptomatic plants of the white cultivar malvasía de banyalbufar. the virus trigge ... | 2016 | 26926417 |
| impacts of grapevine leafroll disease on fruit yield and grape and wine chemistry in a wine grape (vitis vinifera l.) cultivar. | grapevine leafroll disease (gld) is an economically important virus disease affecting wine grapes (vitis vinifera l.), but little is known about its effect on wine chemistry and sensory composition of wines. in this study, impacts of gld on fruit yield, berry quality and wine chemistry and sensory features were investigated in a red wine grape cultivar planted in a commercial vineyard. own-rooted merlot vines showing gld symptoms and tested positive for grapevine leafroll-associated virus 3 and ... | 2016 | 26919614 |
| differential distribution and titre of selected grapevine leafroll-associated virus 3 genetic variants within grapevine rootstocks. | in this study of three grapevine leafroll-associated virus 3 (glrav-3) genetic variants in two grapevine rootstock hosts, glrav-3 detection was shown to be affected by the virus distribution, titre, and the genetic variant. group vi and nz2 glrav-3 variants had reduced detectability compared with the group i variant. differences in the genomic and subgenomic rna (sgrna) expression levels, and differences in the level of expression between the genetic variants were also observed. the observed dif ... | 2016 | 26906692 |
| modeling the accuracy of three detection methods of grapevine leafroll-associated virus 3 during the dormant period using a bayesian approach. | grapevine leafroll-associated virus 3 (glrav-3) has a worldwide distribution and is the most economically important virus that causes grapevine leafroll disease. reliable, sensitive, and specific methods are required for the detection of the pathogen in order to assure the production of healthy plant material and control of the disease. although different serological and nucleic acid-based methods have been developed for the detection of glrav-3, diagnostic parameters have not been established, ... | 2016 | 26780435 |
| effects of grapevine leafroll associated virus 3 (glrav-3) and duration of infection on fruit composition and wine chemical profile of vitis vinifera l. cv. sauvignon blanc. | in order to determine the effects of grapevine leafroll associated virus 3 (glrav-3) on fruit composition and chemical profile of juice and wine from vitis vinifera l. cv. sauvignon blanc grown in new zealand, composition variables were measured on fruit from vines either infected with glrav-3 (established or recent infections) or uninfected vines. physiological ripeness (20.4°brix) was the criterion established to determine the harvest date for each of the three treatments. date of grape ripene ... | 2016 | 26675855 |
| interactions within susceptible hosts drive establishment of genetically distinct variants of an insect-borne pathogen. | coinfections are common, leading to pathogen interactions during transmission and establishment in a host. however, few studies have tested the relative strengths of pathogen interactions in vectors and hosts that determine the outcome of infection. we tested interactions between two genetically distinct variants of the mealybug-transmitted grapevine leafroll-associated virus 3. the transmission efficiency of each variant in single variant inoculations by two vector species was determined. the e ... | 2015 | 26470292 |
| phylogenomic analysis reveals deep divergence and recombination in an economically important grapevine virus. | the evolutionary history of the exclusively grapevine (vitis spp.) infecting, grapevine leafroll-associated virus 3 (glrav-3) has not been studied extensively, partly due to limited available sequence data. in this study we trace the evolutionary history of glrav-3, focussing on isolate gh24, a newly discovered variant. gh24 was discovered through the use of next-generation sequencing (ngs) and the whole genome sequence determined and validated with sanger sequencing. we assembled an alignment o ... | 2015 | 25992606 |
| relative quantitation goes viral: an rt-qpcr assay for a grapevine virus. | accurate detection and quantitation of viruses can be beneficial to plant-virus interaction studies. in this study, three sybr green real-time rt-pcr assays were developed to quantitate grapevine leafroll-associated virus 3 (glrav-3) in infected vines. three genomic regions (orf1a, coat protein and 3'utr) were targeted to quantitate glrav-3 relative to three stably expressed reference genes (actin, gapdh and α-tubulin). these assays were able to detect all known variant groups of glrav-3, includ ... | 2014 | 25286180 |
| pseudococcus maritimus (hemiptera: pseudococcidae) and parthenolecanium corni (hemiptera: coccidae) are capable of transmitting grapevine leafroll-associated virus 3 between vitis x labruscana and vitis vinifera. | the grape mealybug, pseudococcus maritimus (ehrhorn), and european fruit lecanium scale, parthenolecanium corni (bouché), are the predominant species of coccoidea in washington state vineyards. the grape mealybug has been established as a vector of grapevine leafroll-associated virus 3 (glrav-3) between wine grape (vitis vinifera l.) cultivars, elevating its pest status. the objective of this study was to determine if glrav-3 could be transmitted between vitis x labruscana l. and v. vinifera by ... | 2013 | 24468559 |