Molecular diagnosis of new isolate of tomato yellow leaf curl virus in Iraq

Abstract

Tomato yield and quality in Iraq have been threatened by a variable range of infections caused by tomato yellow leaf curl virus. In previous studies, the TYLCV isolates were characterized using molecular tests for small fragments not the entire length of the virus. As a part of long term study, sample of slightly TYLCV-infected tomato has applied in this study to figure out complete sequence of TYLCV isolate. Three sets of primers that belong to three well-known isolates in Iraq were used in a PCR technique and interestingly the results were negative. A new Iraqi isolate has been characterized as a first novel Iraqi isolate detected ever using next generation (NGS) and bioinformatics techniques. The NGS platform has produced about 78,232,062 paired reads of the TYLCV-infected tomato var. Oula F1. The complete raw reads of the infected variety have been analyzed using RepeatExplorer pipeline and Map to reference. The full sequence of TYLCV was reconstructed and extracted to consist of 2770 nt and then deposited in Genbank under accession number MT583814. Copy numbers and genome proportion of this sequence have been calculated that were 3523 and 0,086% respectively. Phylogenetic analyses of full nucleotide sequences confirmed close relationship to Iranian isolate (TYLCV-Kahnooj) than other published viruses. Additionally, a and β DNA satellites have not discovered in the TYLCV-infected sample.