Molecular Virology Lab, National Research Centre For Banana (ICAR), Thogamali main road, Thayanur (Post), Tiruchirapalli.
Banana bract mosaic virus (BBrMV) is an important disease in India and Southeast Asia. In India, this disease was known as Kokkan in Kerala, subsequently it has been proved to be bract mosaic virus disease. The virus infects Nendran, Poovan, Rasthali, Ney Poovan and Robusta. It causes a loss of Rs 38 crores every year for Nendran banana growers. The virus belongs to the family Potyviridae and the genus Potyvirus. Early diagnosis becomes a major step in avoiding virus infection in banana as a control strategy. In this study we have compared three techniques such as Direct Antigen Coating Elisa (DAC-ELISA), Dot Immuno Binding Assay (DIBA) and Reverse Transcriptional Polymerase Chain Reaction (RT-PCR). Polyclonal antiserum for BBMV used was obtained from J.E. Thomas, Australia. BBrMV specific primers were used for virus detection in RT-PCR. Partially purified BBrMV and also the leaf extract from infected Ney Poovan were used for detection and comparison. Among serological techniques DIBA is 10 times more sensitive than DAC-ELISA for detecting the virus from the extracted sap from infected plant. RT-PCR found more sensitive than these two serological techniques. RT-PCR could detect the virus preparations diluted up to 500 times. The virus concentration was more in younger leaf tissues. Details on problems faced while detecting the virus in different tissues and varieties are discussed.
