Occurrence of Diverse Recombinant Strains of Potato virus Y Circulating in Potato Fields in Egypt.

Potato is one of the staple crops in Egypt， grown under irrigation almost continuously year-round. Potato virus Y (PVY) has been reported as one of the main viruses affecting potatoes in Egypt， but limited information is available on PVY strains circulating in potato fields in the country. From 2014 to 2016， virus surveys were conducted in several potato-growing governorates of Egypt， and PVY-positive samples were found to represent at least five distinct recombinant PVY strains， including PVY and PVY. Whole genome sequences were determined for four isolates representing strains PVY-SYR-III (Egypt7)， PVY-261-4 (Egypt11)， PVY (Egypt35)， and a novel recombinant named Egypt24 that combined molecular properties of strains PVY-261-4 and PVY-Wilga156var. At least three recombinants found in Egypt in potato were previously found associated with potato tuber necrotic ringspot disease (PTNRD). The identification of multiple recombinant types of PVY in potato in Egypt， including the novel recombinant Egypt24， suggests a wide presence of PTNRD-inducing virus strains in the country.