Incidence and Molecular Characterisation of Viruses Infecting Wheat in Eastern Anatolia (Turey)

Abstract

In order to assess the occurrence and the incidence of Barley yellow dwarf viruses (BYDV-PAV, BYDV-SGV, CYDV-RPV, BYDV-MAV, BYDV-RMV), Wheat streak mosaic virus (WSMV) and Soil borne wheat mosaic virus (SBWMV) in eastern Anatolia, a survey was conducted in wheat fields from 10 major wheat-growing provinces in Turkey from April 2012 to June 2013. A total of 900 wheat samples were collected and reverse-transcription polymerase chain reaction (RT-PCR) and multiplex RTPCR tests were implemented to detect seven wheat viruses. In wheat fields, BYDV-PAV was the most common. followed by BYDV-SGV, CYDV-RPV and WSMV, respectively. BYDV-MAV, BYDV-RMV, and SBWMV were not detected in tested samples. Since the SBWMV has been transmitted by soil borne fungus Polymyxa graminis, further research was performed to determine the presence of SBWMV and its fungus vector in soil samples by bait plant method, None of the green parts and roots of the bait plants were found infected by SBWMV and P. gratninis, respectively. In the wheat fields of eastern Anatolia, total virus incidence ranged from 0,4 to 6.8%. Based on field observations, the incidence of surveyed viruses in all wheat fields was less than 7 %. Since detected viruses have been considered the most economically relevant viruses of wheat fields, we further characterized randomly selected isolate of each detected virus by cloning the complete coat protein gene and sequencing [(Accession numbers; BYDV-PAV (KC900900), CYDV-RPV (KC900903), BYDV-SGV (partial) (KC900899) and WSMV (KC900901)]. Nucleotide sequence identities for the coat protein gene (CP) ranged from 82 % to 94 % (PAV), 69 % to 96% (SGV), 83% to 96 % (CYDV-RPV), and from 88 0 to 97 % (WSMV). This is the first report of BYDV-PAV, BYDV-SGV, CYDV-RPV and WSMV infecting wheats in eastern Anatolia (Turkey).