Direct nucleotide sequencing of citrus exocortis viroid (CEV)

Citrus exocortis viroid (CEV). the causal agent of bark shelling disease in Poncirus trifoliate (L.) Raf. can be distinguished by its biological properties in Etrog citron and Gynura aurantiaca D.C. CEV isolate obtained from citrus trees of Çukurova region was reverse transcribed and subsequently amplified in vitro from total nucleic acid extracts of infected tissues using a reverse transcription-polymerase chain reaction assay (RT-PCR). The amplified products were gel purified, and subsequently sequenced without cloning, using the Promega fmol sequencing system. Both CEVc (citron) and CEVg (Gynura) were determined 371 nucleotides (nts) in length. Comparing the nucleotide sequence of CEV isolate from Çukurova region and California isolates of CEV, a number of exchanges were found in the pathogenic and variable domains

Nucleotide sequence of CVd-Ib and CVd-IV viroids collected from citrus gummy bark-diseased sweet orange trees in the east Mediterranean region of Turkey [Nukleotidsequenz der Zitrusviroide CVd-Ib und CVd-IV aus Citrus gummy bark erkrankten Sussorangen an der ostlichen Mittelmeerkuste der Turkei]

Two citrus viroids CVd-Ib and CVd-IV, collected from citrus gummy bark- diseased sweet orange trees in the Turkey, were amplified using RT-PCR and directly sequenced from gel-purified products by the Promega finol sequencing system. CVd-Ib, a member of the apple scar skin viroid (ASSVd) family, was determined 317 nucleotides in length and CVd-IV, a natural chimeric viroid of citrus exocortis viroid (CEVd) was found 285 nts in length. The obtained nucleotide sequences of both viroids were compared with the type strains of CV-Ib and CVd-IV previously sequenced from avocado and grapefruit in Israel

First report of hop latent viroid in Turkey

This study reports the identification of hop latent viroid (HLVd) in commercial hop (Humulus lupulus L.) plants in the Pazaryeri region, Bilecik province, in Turkey. Hop plants without clear symptoms were randomly collected during 2015 and 2016 surveys. A total of 210 samples were collected from commercial cultivars Erciyes, Brewers Gold, Aroma and Ege. RNA was extracted using the GeneJET Plant RNA Purification Mini Kit and used in one step RT-PCR with specific HLVd primer pair 5'- CCACCGGGTAGTTTCCAACT-3' and 5'-ATACAACTCTTGAGCGCCGA-3' and protocols described by Eastwell and Nelson (2007). HLVd was detected in 20 out of 210 plant samples. The amplified DNA products of the expected size (ca. 260 nts) were purified and directly sequenced. Direct sequencing of the PCR products (Molgantec, Turkey) confirmed the presence of HLVd in these plants. Blast analyses and dendograms of HLVd sequences performed using the Mega 7 (Kumar et al., 2016) showed 97% to 98% maximum nucleotide identity with GenBank accession numbers KT600318 (Belgium) and EF613181 (China). Four HLVd isolates were graft transmitted from infected to healthy hop plants. All inoculated plants were found to be positive for HLVd in the RT-PCR tests and none of them exhibited any specific symptoms. To our knowledge, this is the first report of HLVd on hop plants in Turkey. © 2017, Edizioni ETS. All rights reserved

First report of citrus viroid v in Turkey

[No abstract available

First report of grapevine viroids in the east Mediterranean region of Turkey

[No abstract available

First report of dahlia latent viroid in Turkey

Dahlia (Dahlia sp.) is a host of dahlia latent viroid (DLVd), but no information is available on the occurrence of this viroid in Turkey. Thirty asymptomatic dahlia plants were randomly selected in gardens of the cities of Gaziantep and Adana (Turkey) for this study. Total RNA was extracted from approximately 200 mg of leaf tissue of the sampled plants with AxyPrep Multisource Total RNA Midiprep Kit (Axygen Biosciences, USA) and screened by RT-PCR with primers DLVd-P1 (5'-GGGGCTCCTCAGAGAGTCTC-3') and DLVd-P2 (5'- GGGGCAACTCCGAGAGTGCTG-3') (Verhoeven et al., 2013). Twelve plants proved to be infected with DLVd. The amplified DNA bands of the expected size (ca. 340 nucleotides) were purified and directly sequenced. The sequence of five DLVd genetic variants from Turkey showed 98 to 100% maximum nucleotide identity with a genetic variant from the Netherlands (GenBank accession No. JX263426). The occurrence of DLVd in dahlia was confirmed by viroid purification and sequential polyacrylamide gel electrophoresis (Semancik et al., 1988). To our knowledge, this is the first report of DLVd on dahlia plants in Turkey. © 2017, Edizioni ETS. All rights reserved

First report of citrus yellow vein clearing virus infecting new natural host plants in Turkey

[No abstract available