Diagnosis of banana bunchy top virus in Red banana

Banana Bunchy Top Disease (BBTD) caused by the Banana Bunchy Top Virus (BBTV), is the most serious virus disease of banana and plantain worldwide. Detection of the BBTV infection in the planting material could help in the effective management of the disease in banana. A polymerase chain reaction (PCR) assay was used to detect the of banana bunchy top virus at early stages of infection in banana suckers before the expression of symptoms. In the present study, primers were designed for amplification of the BBTV coat protein (CP) gene and the gene of 513 bp size was successfully amplified through polymerase chain reaction (PCR). The amplified PCR product was cloned and sequenced. The homology search of the sequence using NCBI blast showed similarity (99%) to ten CP gene sequences and are 98% similar to four CP gene sequences. 40 randomly selected banana suckers were subjected for the detection of BBTV through PCR. Out of 40, size specific amplification of coat protein gene was found, which indicates infection of planting material with BBTV. The PCR result was confirmed and validated through Dot blot hybridization analysis by using sequences of BBTV CP gene as probe.