Detection and geographical distribution of viral infections in cucumber greenhouses in Tehran and Alborz provinces

Viral infection is one of the most important factor causing high yield losses of cucurbit crops in greenhouses and open fields grown condition. Mosaic and yellowing are the most prevalent symptoms in cucumber greenhouses in all over the world and Iran. Surveys were conducted from 2010 to 2011 in some cucumber greenhouses of Tehran and Alborz provinces and 219 leaf samples showing mosaic and yellowing symptoms were collected. The samples were tested for the presence of some prevalent cucurbit viruses by DAS-ELISA and RTPCR. These results confirmed the presence of viral infection (~51%) in cucumber greenhouses and showed the infection of some samples to different viruses in different genus and families in all surveyed areas. Samples showing yellowing symptoms were also tested for the presence of viruses which involved or associated with yellowing symptom. DAS-ELISA and RT-PCR results confirmed the presence of CABYV، ZYMV، and CYSDV. This is the first report of CABYV and CYSDV from cucumber greenhouses in Iran. CABYV، CYSDV، and ZYMV were the most prevalent viruses in cucumber greenhouses. Mixed infections were found in ~19% of infected samples. Double infections were the most frequent of mixed infections and CABYV is the key role in double and triple infections. In order to CABYV strains identification (strain C and strain R)، RT-PCR was carried out using specific primers. The samples were only infected with strain (C). Cucumber samples showing yellowing symptoms were also tested for whitefly-transmitted geminiviruses (WTGs) infection، using specific and degenerate primers in PCR. Despite of the presence of high population whiteflies and yellowing symptoms in many surveyed greenhouses، the samples were negative to WTGs infection.