S. Shoushtari - MSc Student , Department of Plant Protection, Collage of Agriculture, Ferdowsi University of Mashhad, Respectively
B Jafarpour - Professor, Department of Plant Protection, Collage of Agriculture, Ferdowsi University of Mashhad, Respectively
M. Falahaty Rastegar - Professor, Department of Plant Protection, Collage of Agriculture, Ferdowsi University of Mashhad, Respectively

In order to investigate the presence of Tomato spotted wilt virus ( TSWV) in tomato fields of Khorasan Razavi province ( Mashhad , Neishabour , Torbat-e-Hydarieh , Kashmar , Ghochan , Fariman , Takht-e-Golgeh and Roshtkhar ), totally 636 samples were collected from tomato fields in summer of 2008 and 2009 . The plant that showed symptoms of chlorotic , necrotic and ring spot were collected and transferred to the laboratory in cold condition , then tested by TAS-ELISA . Sap from infected plants inoculated to 3 cultivars of indicator plant e.g Nicotiana rustica, N . clevelandii and N. tabacum var Samsun . To confirme symptomology, inoculated indicator plants tested by TAS-ELISA. For molecular detection, RNA extracted by use of RNX TM(plus) kit . In RT-PCR , specific primer , amplified a fragment of 276 bp . Using RT-PCR and mechanical transmission tests , the presence of TSWV has been proven in tomato field of the province .In inoculating indicator plants only Nicotiana tabacum var Samsun (leaf deforming and mottling ) showed specific virus symptoms .

Mechanical transmission, RT-PCR, Tomato spotted wilt virus