Characterisation of a Geminivirus Infecting Cassava in Sri Lanka

Abstract

A geminivirus, related to Indian cassava mosaic virus (ICMV) was detected in fifteen samples of cassava collected from different areas of the island. The virus was transmitted by sap inoculation to herbaceous hosts and graft inoculation to cassava. The isolates tested showed a narrow host range. The virus was detected in many varities of Manihot esculenta and ceara rubber (wild cassava) by enzyme linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). The virus was purified from systemically infected Nicotiana benthamiana leaves. Geminate particles of 18-20x 30 nm in size were observed by electron microscopy. An atiserum was prepared and the titre was found to be 1/32 as determined by gel double diffusion. This polyclonal antiserum detected geminiviruses of Acalypha mosaic disease and Ageratum yellow vein disease but not the geminivirus of Hibiscus yellow vein disease in indirect ELISA.