FIRST REPORT OF SOLANUM ELAEAGNIFOLIUM AS NATURAL HOST OF TOMATO YELLOW LEAF CURL VIRUS SPECIES TYLCV AND TYLCSV IN TUNISIA
S. Zammouri, M. Mnari-Hattab
Tomato yellow leaf curl virus (TYLCV) and Tomato yellow leaf curl Sardinia virus (TYLCSV) (genus Begomovirus, family Geminiviridae), as well as recombinant variants, were recently found in tomato in Tunisia (Mnari-Hattab et al., 2014). To identify sources of infection, tomato plants and Solanum elaeagnifolium, an invasive weed, were sampled and tested for the presence of TYLCV and TYLCSV. Genomic DNA was purified from leaf samples showing curling and yellowing and subjected to PCR using primers designed in the coat protein gene of TYLCV (Mnari-Hattab et al., 2014; Wyatt and Brown, 1996). A product of ca. 580 bp was obtained from four of six S. elaeagnifolium and six of six tomato samples tested. The nucleotide sequence of one amplicon from tomato and two amplicons from S. elaeagnifolium was obtained and deposited in GenBank as accession numbers KF990598, KF990599 and KF990600. The nucleotide sequence of Tunisian TYLCV isolates was 91.2 to 98.9% identical and shared 91 to 98.3% identity with a TYLCV isolate from Turkey (AJ867487). Multiplex PCR (Davino et al., 2008) was further used to identify virus species with the amplification of a 570 bp fragment for TYLCV and a 800 bp fragment for TYLCSV. Results showed two S. elaeagnifolium and four tomato plants infected with TYLCV or TYLCSV, and two S. elaeagnifolium and one tomato plant infected with both viruses. To the best of our knowledge, this is the first report of S. elaeagnifolium as a natural host of TYLCV and/or TYLCSV in Tunisia. These findings suggest S. elaeagnifolium as a reservoir for tomato yellow leaf curl virus disease.