[Show abstract][Hide abstract] ABSTRACT: A survey on maize virus diseases was conducted in the Trakya region of Turkey by examining 32 496 and 46 871 plants in 2004 and 2005, respectively. Rates of symptomatic plants were estimated at 3.7 to 63.6%, depending on locations. Biological and serological test results revealed the presence of barley yellow dwarf virus-PAV (BYDV-PAV), maize dwarf mosaic virus (MDMV), sugarcane mosaic virus (SCMV), and Johnson grass mosaic virus (JGMV). One hundred forty-two samples were collected ran- domly from 6492 symptomatic plants in 2004. Seventy-two out of the 142 samples were infected with MDMV, two were infected with BYDV-PAV, 19 with MDMV and BYDV-PAV, two with MDMV, BYDV-PAV and SCMV, and only one sample contained the four viruses. In 2005, 100 other leaf samples were collected randomly from 11 739 symptomatic maize plants. Serological tests revealed that 50% of the samples were infected with MDMV and SCMV; however, five showed mixed infections of two or three combinations of tested viruses. Individual MDMV, SCMV, BYDV-PAV and JGMV infections were detect- ed in five, three, two and four samples, respectively. Presence of MDMV was confirmed by Western blot analysis and IC-RT-PCR. SCMV was also detected by IC-RT-PCR. This is the first study reporting the detection of SCMV and JGMV on maize plants in Turkey.
Full-text · Article · Aug 2014 · Phytoprotection -Quebec-
[Show abstract][Hide abstract] ABSTRACT: The Bursa and Sakarya provinces in the south eastern part of Marmara region in Turkey [(39°.34 1) -41°.10 1 N, 28°.05 1 -30°.54 1 E] are very important fruit-growing areas. Leaf samples from 12 symptomless pear trees and six quince trees showing typical symptoms of quince fruit de-formation disease (Nemeth, 1986), including leaf chlorosis and curling, mosaic, vein banding, and deformation, were collected in June 2009 and tested for the presence of Apple stem pitting virus (ASPV), genus Foveavirus, family Betaflexiviridae. RT-PCR for the generic detection of foveaviruses was used with degenerate primers that target a conserved region of the RNA-dependent RNA poly-merase gene, followed by a nested PCR that amplifies a 312 bp ASPV-specific product (Mathioudakis et al., 2009). The virus was present in all pear and quince samples tested (GenBank accession Nos FN432827 and FN432828, re-spectively). Direct sequencing of two RT-PCR amplicons, one from pear and one from quince, confirmed the identi-fication of ASPV. The pear isolate (ASPV-Pe) showed 83.0% nucleotide sequence identity with a pear isolate of ASPV (accession No. FN386784) whereas the quince iso-late (ASPV-Qui) showed 84.0% nucleotide sequence iden-tity with an apple isolate of ASPV (accession No. FN386781). Nucleotide sequence comparison among AS-PV-Pe and ASPV-Qui isolates revealed a 78.7% similarity. To our knowledge, these findings represent the first report of ASPV in pear and quince orchards in northern Turkey.-tis N.I., 2009. Reliable RT-PCR detection of Apple stem pit-ting virus in pome fruits and its association with quince fruit deformation disease. Plant
[Show abstract][Hide abstract] ABSTRACT: Canary seed (Phalaris canariensis L.) is a cereal crop belonging to the tribe Phalarideae of the Poaceae family. A prevailing virus infection, which causes dwarfing of plants and yellowing of leaves, was observed in canary seed fields in the Tekirdag province of Turkey. The aim of this study was to identify, clone and sequence the cereal viruses naturally occurring on P. canariensis by employing serological tests as DAS-ELISA and TAS-ELISA tests combined with transmission electron microcopy (TEM) and molecular analysis. One hundred and one plant samples showing symptoms were collected and tested serologically using polyclonal antisera against Barley yellow dwarf virus-PAV (BYDV-PAV) and Cereal yellow dwarf virus-RPV (CYDV-RPV). The results of both immunoassays showed that 48% of the samples were infected with BYDV-PAV, 2% with CYDV-RPV and 14% were mixed infection. 36% of the samples were uninfected or infected at level below detection. Aphid transmission experiments revealed that barley (cv. Rubina) exhibited characteristic of CYDV-RPV. Investigations of infected canary grass seedlings using transmission electron microscopy (TEM) supported the findings of serological tests and revealed the presence of isometric particles of approximately 25 nm in diameter. These results were also confirmed by using BYDV-PAV and CYDV-RPV specific primers. Sequence analysis of cDNA and probable translation products revealed a high level of homology to BYDV-PAV and CYDV-RPV isolates found in other plant species. The sequence data obtained from this research were deposited in the EMBL/GenBank Data Libraries under the accession nos. EGO19056 and EF372272.
Full-text · Article · Jun 2008 · Cereal Research Communications
[Show abstract][Hide abstract] ABSTRACT: A reverse transcription-polymerase chain reaction (RT-PCR) procedure was developed to detect Amasya cherry disease (ACD) in naturally infected sweet cherry (Prunus avium) leaves sampled from Turkey. The procedure was based on detection of the presence of a mycoviral-like double-stranded RNA (dsRNA) of 5·3 kbp always found in association with ACD, which is probably caused by a fungus. Specific primers were designed to amplify a fragment of the diagnostic dsRNA. The method will improve routine diagnosis of ACD in Prunus spp.
[Show abstract][Hide abstract] ABSTRACT: The sequence of the four large (L) double-stranded RNAs (dsRNAs) associated with Amasya cherry disease (ACD), which has a presumed fungal aetiology, is reported. ACD L dsRNAs 1 (5121 bp) and 2 (5047 bp) potentially encode proteins of 1628 and 1620 aa, respectively, that are 37% identical and of unknown function. ACD L dsRNAs 3 (4458 bp) and 4 (4303 bp) potentially encode proteins that are 68% identical and contain the eight motifs conserved in RNA-dependent RNA polymerases (RdRp) of dsRNA mycoviruses, having highest similarity with those of members of the family Totiviridae. Both terminal regions share extensive conservation in all four RNAs, suggesting a functional relationship between them. As ACD L dsRNAs 1 and 2 do not encode RdRps, both are probably replicated by those from either ACD L dsRNA 3 or 4. Partial characterization of the equivalent L dsRNAs 3 and 4 associated with cherry chlorotic rusty spot revealed essentially identical sequences.
Full-text · Article · Nov 2006 · Journal of General Virology
[Show abstract][Hide abstract] ABSTRACT: Two dsRNAs from cherry trees affected with cherry chlorotic rusty spot (CCRS) in Italy and Amasya cherry disease (ACD) in Turkey were sequenced and found to be essentially identical. The larger dsRNA 1 (2021 or 2006 bp, respectively) potentially encoded a protein of 621 aa containing the conserved motifs of the RNA-dependent RNA polymerases (RdRp) of dsRNA mycoviruses, having highest similarity with those in the genus Partitivirus. The smaller dsRNA 2 (1841 or 1839 bp, respectively) had properties consistent with the second genomic component of a partitivirus and potentially encoded the coat protein (CP) of 504 aa. Phylogenetic analysis based on the RdRp and CP was coincidental and indicated that species in the genus Partitivirus could be separated into two subgroups. Because species of this genus only infect fungi, these observations suggest a fungal aetiology for CCRS and ACD, further substantiating a previous proposal (see accompanying paper by Covelli et al., 2004, in this issue).
Full-text · Article · Dec 2004 · Journal of General Virology
[Show abstract][Hide abstract] ABSTRACT: Cherry chlorotic rusty spot (CCRS) and Amasya cherry disease (ACD) display similar symptoms and are associated with a series of dsRNAs. However, a direct comparison has been lacking. Here, a side-by-side analysis confirmed that both diseases were symptomatologically very similar, as were the number (10-12) and size of their associated dsRNAs. Sequence determination of four of these dsRNAs revealed that they were essentially identical for CCRS and ACD. The largest (3399 bp), which potentially encoded a protein of 1087 aa with the eight motifs conserved in RNA-dependent RNA polymerases of dsRNA mycoviruses, had the highest similarity to those coded by dsRNA 1 of viruses belonging to the genus Chrysovirus and was termed CCRS or ACD chrys-dsRNA 1. The three closely migrating dsRNAs had the properties of the other components of a chrysovirus and in CCRS and ACD versions, respectively, were chrys-dsRNA 2 (3125 and 3128 bp), chrys-dsRNA 3 (2833 bp) and chrys-dsRNA 4 (2499 and 2498 bp), potentially encoding the major capsid protein (993 and 994 aa) and two proteins (884 and 677 aa, respectively) of unknown function. The four 5'- and 3'-UTRs shared internal similarities and had conserved GAAAAUUAUGG and AUAUGC termini, respectively. The 5'-UTRs contained the 'Box 1' motif followed by a stretch rich in CAA, CAAA and CAAAA repeats, characteristic of chrysovirus dsRNAs. Because species of the genus Chrysovirus have only been described as infecting fungi, this suggests a fungal aetiology for CCRS and ACD, a proposal supported by the properties of two other CCRS- and ACD-associated dsRNAs (see accompanying paper by Coutts et al., 2004, in this issue).
Full-text · Article · Dec 2004 · Journal of General Virology