identification and sequencing of coat protein gene of tylcv isolates from khorasan razavi southern and northern khorasan provinces

tomato yellow leaf curl virus (tylcv) is considered as one of the most important tomato viruses in tropical and subtropical areas. in order to identify and investigate the presence of this virus in fields , greenhouses and cultivated tomato plants in tuneles of khorasan razavi, southern and northern khorasan provinces, during 2009 and 2011, plants which have been showed the symptoms were collected. total dna was extracted from fresh young leaf tissue by ctab buffer. polymerase chain reaction (pcr) was carried out using degenerate primers shown to be specific for dna-a of whitefly transmitting geminiviruse and fragments of ~550 bp were amplified by pcr. furthermore, with a pair of tylcv specific primer, a viral dna fragment of 776 bp corresponding to a complete coat protein gene was amplified and cloned. the phylogenetic tree of coat protein (cp) gene of tylcv were drown, by mega5 software using neighbor joining method. the results showed that the khorasan razavi and northern khorasan provinces placed in one group with shiraz (gu076444) and israel (ab110218) isolates. and isolate from southern khorasan was located in different group and closed to iranian isolate of tylcv-jiroft (gu076452) and one isolate from omman (dq644565). this study showed that since the first report of tylcv in the southern provinces of the country, the virus spreading towards the higher latitudes, so that the high rate of infection in the city of neyshapur and dargaz is explored in this study.