First report of canna yellow streak virus in Iran

Canna indica (canna) a species in the Cannaceae family, is a perennial ornamental plant widely used in landscape designing. Different species of plant viruses have been reported which infect this plant and act as a significant threat to canna plants, leading to a range of symptoms and a decrease in their decorative values, as well as lower quality propagated materials and significant financial losses. Canna cultivars that are extensively cultivated for their ornamental values are susceptible to a recently discovered Potyvirus known as canna yellow streak virus (CaYSV). This virus has infected many canna cultivars found in gardens, leading to significant impact and concern in horticultural settings. During a survey conducted in the summer of 2022, severe veinal chlorosis and veinal streaking symptoms were observed on the leaves of canna plants in the green space of Yazd City, Iran. Total genomic RNA was extracted from symptomatic leaves of 20 canna samples and one symptomless sample (negative control), and subjected to RT-PCR using a potyvirus degenerate primer pair (NIb3R, NIb2F). RT-PCR resulted in the amplification of a DNA fragment with the expected size of approximately 350 bp in all of the symptomatic samples, whereas no DNA fragment was obtained from a symptomless plant. The amplified DNA fragment was subjected to the Sanger sequencing method, and its size was confirmed to be exactly 350 bp. Sequence analysis of the nucleotide sequence of this amplicon with the same region of other corresponding CaYSV isolates in the GenBank revealed that the Iranian CaYSV isolate was the most similar (99.05%) to an isolate from Russia (Acc. No.  MG_545919.1) and the less similar (89.59%) to a CaYSV isolate from United Kingdom (Acc. No.  EF_466139.1).