Identification and distribution of Tomato yellow leaf curl virus TYLCV and Tomato yellow leaf curl Sardinia virus TYLCSV infecting vegetable crops in Morocco

Leaf samples of 177 tomato plants were collected during 2006-2007 in tomato yellow leaf curl disease (TYLCD) infected fields, as well as 100 leaf samples of sweet pepper, common bean, zucchini and the wild species Solanum elaeagnifolium, in order to study the population structure and genetic variation of Tomato yellow leaf curl Sardinia virus (TYLCSV) and Tomato yellow leaf curl virus (TYLCV) in Morocco. Molecular hybridization using specific probes and restriction of a genomic region corresponding to the coat protein gene were performed to differentially identify TYLCV and TYLCSV species. Both species were present in the infected plants from Southwestern and Northern Morocco analyzed in this study. This is the first report of the presence of TYLCD in Northwest area. 66% of the tomato samples and 37.8% pepper were infected, most of them with mixed infections. The rest of the species analyzed were virus free. Five of the six Moroccan haplotypes identified had previously been reported. We identified a new haplotype representing 76% of the TYLCSV infected samples collected in Agadir-Chtouka-Ait-Baha area. The genomic region corresponding to the CP gene was sequenced for 10 isolates. The TYLCV and TYLCSV sequences had 99% identity with those previously identified in Northern Morocco and of Murcia respectively. Key words: Tomato yellow leaf curl Sardinia virus (TYLCSV), Tomato yellow leaf curl virus (TYLCV), molecular hybridization, population structure, genetic variation.