First report of the incidence of potato virus Y in some ornamental plants in Iran

During the surveys conducted from green space in Shiraz City, Iran, in the summer of ۲۰۲۲, leaf chlorosis and mosaic symptoms were observed on the leaves of black-eyed-susans (Rudbeckia hirta), a  Dahlia sp., and Mexican Petunia (Ruellia brittoniana) plants. Total genomic RNA was separately extracted from ۱۰ symptomatic and one symptomless (negative control) leaf samples and subjected to Reverse Transcription-Polymerase Chain Reaction (RT-PCR) using a potyvirus degenerate primer pair (NIb۳R, NIb۲F). RT-PCR resulted in the amplification of an approximately ۳۵۰ bp DNA fragment in all symptomatic samples, while no such fragment was amplified from the symptomless plant. The amplified DNA fragment was subjected to Sanger sequencing, and its size was determined to be exactly ۳۵۰ bp, and confirmed that it belongs to the Nib gene of potato virus Y (PVY). The nucleotide (nt) sequence of the amplicons was compared with the nt sequence of the same region of some other PVY isolates that were available in the GenBank. The sequence analysis revealed that the R. brittoniana isolate exhibited the highest (۹۸.۸%) similarity to a PVY isolate from the USA with the Acc. No. of KY_۸۴۸۰۲۹.۱. Similarly, the R. hirta and the Dahlia isolates showed the highest (۹۸.۳%, ۹۸.۴ %, respectively ) similarity to a PVY isolate from Kazakhstan with the Acc. No. of ON_۵۸۳۹۸۰.۱.

Keywords:

Degenerate primers , Green space , Potyvirus , Ornamental plants , Shiraz