Maize chlorotic mottle virus (MCMV) is one of the co‐infection pathogens that cause corn (maize) lethal necrosis, but the transmission mechanism of MCMV is not yet clear. In order to determine the ability of western flower thrips (Frankliniella occidentalis; WFT) to transmit MCMV, imported maize seeds from Thailand were germinated in an insect‐free greenhouse and the seedlings were tested for the transmission by WFT of chlorotic mottle virus disease. The thrips (WFT), starved for 48 h then allowed to feed for 30 min on maize plants infected with MCMV or asymptomatic maize plants, were transferred to healthy seedlings. After 35 days, the seedlings with WFT from diseased maize plants showed chlorotic mottle symptoms, whereas seedlings with WFT from asymptomatic maize plants remained healthy. A single band of 711 bp was amplified by RT‐PCR using primers MCMV‐F/MCMV‐R from the MCMV‐infected plants and WFT collected from the diseased plants. Sequencing of the amplified product and further sequence comparison indicated that the two viruses from both sources showed 99% similarity of nucleotides and they should be regarded as identical. In addition, isometric particles c. 30 nm in diameter, characteristic of MCMV, were found in the WFT samples from diseased maize plants. Thus, it is concluded that WFT transmits MCMV. Our findings suggest that corn lethal necrosis disease can be controlled or minimized by the eradication of WFT from the field or greenhouses.

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A novel virus, Paris virus 2 (ParV2), was isolated from diseased Paris polyphylla var. yunnanensis, and its complete genome sequence was determined and analyzed. ParV2 is a positive-sense single-stranded RNA (+ssRNA) virus with a genome size of 4118 nucleotides. The ParV2 genome contains six putative open reading frames (ORFs) that encode proteins with predicted molecular weights of 40.14, 100.26, 7.31, 7.85, 26.09, and 8.77 kDa. The rst ORF (ORF1) of ParV2 encodes a putative protein of 40.14 kDa (p40, nt: 20-1096), whiles the second ORF (ORF2, 888 aa) containing the GDD motif encodes the highly conserved RNA-dependent RNA polymerase protein (RdRP, nt:20-2683, p100, 100.26 kDa) of viruses in the family Tombusviridae. Multiple sequence alignments analysis showed that the complete genome sequence of ParV2 shares 31.7-55.5% nucleotide sequence identities with viruses in the family Tombusviridae. Ginger chlorotic eck-associated tombusvirus (GCFaV-1,Accession No.QKE30557) had the highest sequence identity (55.5%) with ParV2, and also shares 59.2% RdRp and 34.9% CP amino acid sequence identity with GCFaV-1.Sequence comparisons and phylogenetic analysis of RdRp suggested that ParV2 is a novel member of the family Tombusviridae, and its closest known relative is GCFaV-1.