Detection of Viruses Causing Mosaic on Tomato in Fields and Greenhouses of Yazd and strain Determination of Some Tomato Isolates of Potato virus Y (PVY)

Tomato is one of the most important vegetables in Iran and throughout the world with crop loss caused by several viruses. This survey was carried out to detect the viruses causing mosaic symptoms on tomato in Yazd city (Iran). A total of 451 samples of tomato leaves showing mosaic symptoms were collected from fields and greenhouses during 2012-2013 growing season. Collected samples were analyzed by DAS ELISA and ACPELISA using Tobacco mosaic virus (TMV), Cucumber mosaic virus (CMV), Arabis mosaic virus (ArMV) and Potato virus Y (PVY) and Potyvirus genus specific antisera, resulted in positive reaction of 13.5%, 11.3%, 2.6%, 20.6% and 14.5% of symptomatic samples, respectively. According to these results, PVY was determined as the dominant virus among collected samples. To determine the strain of four PVY isolates, a fragment with 837 bp in length of the PVY P1 gene was amplified using P1/P2 primer pair by RT-PCR. Restriction analysis of P1 PCR product using HincII was conducted and two fragments with approximately 400 bp length were produced. Moreover, RT-PCR using PVY strain specific primer pairs revealed that these isolates belonged to NTN group.