Agroinoculation of a full-length cDNA clone of citrus yellow vein clearing virus results in systemic infection in Nicotiana benthamiana and induces disturbances of subcellular structure

Citrus yellow vein clearing virus (CYVCV) is the causal agent of citrus yellow vein clearing disease. In the present study, we performed agroinoculation of a full-length cDNA clone of CYVCV (AY221) to several herbaceous plants, including Nicotiana benthamiana . Molecular and serological detection assays for CYVCV were carried out on the inoculated plants. The results showed that the inoculation induced local infection in broad bean ( Vicia faba L.) and successfully induced systemic infection in ‘Xiaocai’ pea ( Pisum sativum L.) and N. benthamiana . The symptoms included chlorotic mottling and crinkling on the systemically infected leaves of N. benthamiana . Ultra-thin sections of the leaves of CYVCV-infected N. benthamiana and ‘Eureka’ lemon ( Citrus limon Burm. f.) were examined with transmission electron microscopy. Flexuous filamentous particles of the same size and morphology as those of CYVCV were observed in the infiltrated and upper uninoculated leaves of N. benthamiana . Similar pathological changes of subcellular structures were observed in the symptomatic leaves of CYVCV-infected N. benthamiana and ‘Eureka’ lemon plants, and the subcellular disturbances were mainly observed in the chloroplasts, which facilitated understanding of the pathogenesis of CYVCV. The ability of the full-length cDNA clone of CYVCV to induce systematic infection in the model plant N. benthamiana was reported for the first time.