Occurrence of the Israel strain of Tomato yellow leaf curl virus and the whitefly Bemisia tabaci MEAM1 species in French Polynesia.
n 2014, severe symptoms of leaf curling and yellowing resembling those of tomato yellow leaf curl disease were observed for the first time on tomato (Solanum lycopersicum) plants with a 100% incidence in affected greenhouses in Tahiti. Tomato samples with leaf curling and yellowing symptoms, and whiteflies were collected in Tahitian greenhouses from August 2015 to January 2016. Other whiteflies were collected from tomato and melon plants in Huahine and Tubuai islands. Fourteen tomato samples were tested for the presence of begomoviruses using PCR assays with two sets of degenerate primers designed to amplify the coat protein gene of the Old World begomovirus DNA-A component. Sequence analysis and comparison of the PCR products indicated that the samples were infected by Tomato yellow leaf curl virus (TYLCV). This finding was further confirmed by rolling-circle amplification. In parallel, total DNA was extracted from 96 female whiteflies (6-10/greenhouse), sampled from different locations on each island, to identify their species. The core region of the mitochondrial cytochrome oxidase I gene was amplified and sequenced. Sequences of 598 bp were obtained for 92 samples. A single haplotype was retrieved from all three islands and showed 100% pairwise sequence identity (BLAST) with the Middle East-Asia Minor 1 (MEAM1, KM821540) B. tabaci species. This is thought to be the first report of Old World TYLCV-IL implicated in yellow leaf curl disease on tomato in Tahiti. The occurrence of B. tabaci MEAM1 species was reported in 1996-97 in Tahiti, but never on the neighbouring islands of Huahine and Tubuai. This description confirms the invasion and the dissemination of both TYLCV-IL and B. tabaci MEAM1 species in the Asia-Pacific region.