Identification of a potyvirus associated with mosaic disease of Catharanthus roseus and its histopathogical effects

During survey in 2007–08 at Gorakhpur, severe chlorosis, crinkling and curling symptoms was noticed on leaves of Catharanthus roseus plant. The virus was partially purified from the symptomatic leaves by differential centrifugation. Electron microscopy of the partially purified preparation revealed the 760 nm x 14 nm filamentous flexuous particles. The causal virus was found transmitted through mechanical transmission to healthy C. roseus plants as well as through Aphis gossypii, A. nerii, A. craccivora Brevicoryne brassicae, Myzus percicae, and Macrosiphoniella sanbormii. Immuno-diagnostic studies (DAC-ELISA and DIBA) showed positive serological relationships of the causal virus with polyclonal antiserum of Watermelon mosaic virus (WMV). The RT-PCR assays amplified fragment of ~330 bp with coat protein specific primer of WMV The particle morphology, serology and RT-PCR results confirmed that the virus associated with chlorotic leaves of C. roseus in the present study was Watermelon mosaic virus. The virus infection also found to deform the palisade cells in shape and size and number of chloroplast were reduced in tissue of infected leaves under histopathological observation.