Molecular characterization of potyviruses infecting potato and vegetables in Iraq

Abstract

The genetic diversity of potyviruses infecting potato and vegetables in Iraq was determined by reverse transcription polymerase chain reaction (RT-PCR) targeting the 3´ terminal part of the genome. RT-PCR products were cloned and sequenced. Sequence analysis confirmed the occurrence of potyviruses, namely Bean yellow mosaic virus (BYMV) in broad bean, Potato virus Y (PVY) in potato and tomato, and Zucchini yellow mosaic virus (ZYMV) in zucchini squash. BYMV sequences showed maximum nucleotide sequence identity (97.2-98.7%) with isolates from Australia and Japan. Most PVY sequences were very closely related (ca. 99% nucleotide sequence identity) to PVYO: N isolates from USA and Canada, whereas other sequences showed nucleotide identities (98.5-98.7%) with PVYNTN isolates from Poland, UK and Syria. ZYMV sequences showed maximum nucleotide identity (97.9%) with an isolate from Israel. The low genetic diversity amongst Iraqi potyviruses, alongside their high sequence identities with potyviruses from other countries, suggests a relatively recent introduction to Iraq through imported planting materials