Poster Session: Molecular/Cellular/Plant-Microbe Interactions - Proteomics/Metabolomics/Genomics

629-P

Deep sequencing reveals Cotton leaf curl Gezira helper virus and sub-viral DNAs in weed, ornamental, and cultivated crops throughout Arabia.
M. A. Al-Saleh (1), J. K. Brown (2), A. IDRIS (3)
(1) King Saud University, Riyadh, Saudi Arabia; (2) University of Arizona, School of Plant Sciences, Tucson, AZ, U.S.A.; (3) King Abdullah University of Science and Technology, Thuwal, Saudi Arabia

The whitefly-transmitted, monopartite Cotton leaf curl Gezira virus (CLCuGeV), is a monopartite begomovirus that causes vein-thickening and leaf curl symptoms. Leaves of plants with symptoms reminiscent of CLCuGeV infection were collected from hollyhock, Malva spp., and okra plants throughout Arabia. Total DNA was isolated from leaves and used for circular, ssDNA virus enrichment by rolling circle amplification (RCA). RCA products were subjected to Next-Generation Sequencing (NGS) using the Illumina platform. Short reads were assembled, and single nucleotide polymorphisms were identified, for the resultant begomovirus (~2.8 kb) and satellite (~1.4 kb) molecules. Also, the RCA products were digested with restriction enzymes to linearize and enable cloning and sequencing of viral components and satellites. BLASTn analysis of NGS- and RCA-derived products indicated that the begomoviral genomes and satDNAs were most closely related to CLCuGeV, endemic to the Nile Basin, and to close relatives in Jordan and Pakistan thought recently introduced. Several betasatellites, together with CLCuGeV, co-infected three host plant species from four locations. In one location, only defective betasatellites were detected. Nucleotide (nt) sequence comparisons revealed two types of alphasatellites, at 88% and 64% shared nt identity, respectively, with Cotton leaf curl Gezira alphasatellite (DNA-1) and Ageratum yellow vein Singapore alphasatellite (DNA-2) from Oman and Singapore.