ردیابی و تعیین خصوصیات بیولوژیکی و فیلوژنتیکی ویروس وای سیب زمینی (PVY) جدایه استان لرستان

Viral diseases are among the factors limiting potato production in the world. Potato virus Y (PVY) from Potyvirus species of Potyviridae family is one of the most important diseases of potato crop. This virus has a filamentous structure and positive single-stranded RNA and is transmitted mechanically as well as by the green aphid Myzus persicae in non-permanent manner. In order to detect the virus, 135 samples of plants that showed signs of mosaic, dwarf, wavy leaf margin, chlorotic spots and leaf deformation were collected from different potato farms of Khorramabad. Suspicious plant extracts were inoculated on Nicotiana glutinosa and N. occidentalis indicator plants. After about ten days, signs of necrosis, vein clearing and mosaic were observed in the inoculated samples. Total RNA was extracted from symptomatic indicator plants and the band in the range of 1115 bp was amplified using RT-PCR and specific primers of PVY coat protein gene and PVY contamination of the samples was confirmed.. The amplified fragment was sent to Macrogen Company of South Korean and sequenced. Phylogenetic studies showed that the studied Iranian isolate has 98 to 99.2% genetic similarity with other sequences recorded in this area in the NCBI database. Based on the phylogenetic tree drawn using MEGA7 software, Lorestan isolate was placed in a group next to the isolates related to Germany and an Iranian isolate related to Fars province. The nucleotide sequence of this fragment was recorded in the NCBI database with accession number MT655949 under the name of IAU-Lorestan isolate. This is the first report of PVY contamination of potato fields in Lorestan province using molecular tests.