Molecular characterization of banana bunchy top virus in ornamental banana ( Musa acuminata ssp. zebrina ) from Tamil Nadu, India

Abstract

Banana bunchy top disease (BBTD), caused by banana bunchy top virus (BBTV; Babuvirus musae), is a major constraint in Musa spp. worldwide. A BBTV isolate (MaZ-Slm) infecting ornamental banana (Musa acuminata ssp. zebrina) from Salem was molecularly characterised through PCR amplification, cloning and sequencing of all six circular ssDNA genomic components. The components (1018–1111 bp) contained conserved structural features, including the nonanucleotide motif “TATTATTAC” in the common stem-loop region. Pairwise analysis showed higher nucleotide identity with Pacific-Indian Ocean (PIO) group isolates (91.45–99.72%) than Southeast Asian (SEA) isolates (81.39–91.93%). Phylogenetic analysis of concatenated genome sequences clustered MaZ-Slm within the PIO lineage. Recombination analysis detected a single event in DNA-N, whereas other components showed no recombination. This is the first report of BBTV infecting ornamental banana in India, suggesting that ornamental Musa species may potentially act as reservoir hosts and warranting further epidemiological investigation.