Natural Occurrence of Chilli veinal mottle virus on Capsicum chinense in China.

An outbreak of a viral disease on chili pepper (Capsicum chinense Jacp. cv. Yellow Lantern) occurred in Hainan Province, China during 2003 and 2004. The disease was prevalent in five chili-producing counties surveyed. Leaves of infected plants initially displayed symptoms of dark green banding along veins and later became distorted with striking mosaic. Infected plants had reduced flower numbers and fruit set, resulting in a significant yield loss. The causative virus was characterized and identified as Chilli veinal mottle virus (ChiVMV) (3). An isolate of the virus was obtained via three single lesion passages through Chenopodium amaranticolor and was shown to reproduce the same symptoms on inoculated C. chinense cv. Yellow Lantern. Negative staining of crude extracts of the infected tissue and subsequent electron microscopy revealed flexuous rods of 12 to 13 × 750 nm, typical of a potyvirus. Pinwheel-like inclusion bodies were abundant in thin sections of infected leaves. Purified virus preparations contained one major protein of 32.8 kDa and one minor protein of 28 kDa when fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Both of these protein bands were excised and subsequently analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Multiple peptide fragments from both proteins were identified as arising from ChiVMV capsid protein (CP) (1,2). Therefore, the 32.8-kDa protein is the full-length ChiVMV CP and the 28-kDa protein is presumably a degradation product of the CP. The combined biological and molecular data provided strong evidence that the viral disease on C. chinense was caused by ChiVMV. To our knowledge, this is the first report of ChiVMV infection on C. chinense in China and the first report of C. amaranticolor as an experimental host for ChiVMV. References: (1) P. Chiemsombat et al. Arch. Virol. 143:1855, 1998. (2). J. Joseph and H. S. Savithri. Arch. Virol. 144:1679, 1999. (3) P. Siriwong et al. Plant Pathol. 44:718, 1995.