Journal of Plant Pathology Archive

Abstract:

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.