MOLECULAR IDENTIFICATION AND THE COMPLETE NUCLEOTIDE SEQUENCE OF A TOMATO YELLOW LEAF CURL VIRUS ISOLATE FROM TURKEY
G. Köklü, A. Rojas, A. Kvarnheden
Tomato yellow leaf curl disease (TYLCD) threatens the production of tomatoes both in Turkey and other tomato-growing areas of the world. The disease is caused by several virus species belonging to the genus Begomovirus, family Geminiviridae that are transmitted by the whitefly Bemisia tabaci. There has been no previous information about which virus species/strains occur in tomatoes with TYLCD in Turkey. Therefore, polymerase chain reaction tests using degenerate primers were used to amplify partial sequences (579 bp) of the begomovirus coat protein gene (V1) from samples of diseased tomato plants collected from two major tomato-growing areas of Turkey (Mersin and Mug? la). DNA sequence analyses of three isolates revealed high nucleotide sequence identities to isolates of Tomato yellow leaf curl virus (TYLCV, 97-98%) and tentatively identified them as belonging to that species. In addition, the complete nucleotide sequence was determined for one TYLCV isolate from Mersin (TYLCV-[TR:Mer6:04]). This isolate showed high nucleotide identity (98%) to isolates from the “prototype” strain of TYLCV, and only 92% identity to isolates of the TYLCV mild strain. A phylogenetic analysis confirmed that TYLCV-[TR:Mer6:04] belonged to the widespread “prototype” strain.