Genetic Diversity of Badnaviruses Associated with Bougainvillea in Brazil

Abstract

The genus Bougainvillea is native to South America and is cultivated worldwide for ornamental purposes. To investigate the diversity of bougainvillea badnavirus populations, plants with various types of symptoms from different regions of Brazil were collected and subjected to DNA extraction, PCR, cloning and sequencing. Sequence analysis revealed that clones from the Bras ılia (DF) isolate showed maximum identity of 71.7%. No genetic diversity was observed in partial RT/RNase H sequences of Badnavirus isolates derived from the bougainvillea clones grown in São Paulo (SP) state, which shared a monophyletic group with 100% bootstrap in the tree topology reconstructed by maximum likelihood. One clade consistently supported by 100% bootstrap formed by clones of the samples from Minas Gerais (MG) and Cear a (CE) states and Taiwan was also observed. Furthermore, DF, CE and MG isolates formed a monophyletic group with the Delhi isolate, which may represent a new Badnavirus species that infects bougainvillea. Two Brazilian isolates and one from Taiwan appeared to have recombination sites in the RT and RNase H conserved region of BCVBV. These results demonstrate the existence of at least three probably new bougainvillea badnavirus species or strains, which may be spread, as this ornamental is vegetatively propagated.

Complete genome sequence of Bougainvillea chlorotic vein banding virus in Bougainvillea spectabilis from Brazil

“…Only a small segment (465 bp) of the genomic region between RT + RNase H domains was sequenced, which is not sufficient for accurate identification of virus species in this genus (ICTV 2019). In several badnaviruses from Brazil were sequenced, among them, three isolates were identified as BCVBV, including accession KF600737, which differs in only one nucleotide from isolate BCVBV-UNB-01 (Alexandre et al 2016). However, the sequence size obtained by Alexandre et al (2016) was significantly shorter than ours and Rivas et al (2005), with only 396 bp or 32.25% of the total 1228 bp of the RT + RNase H region.…”

“…In several badnaviruses from Brazil were sequenced, among them, three isolates were identified as BCVBV, including accession KF600737, which differs in only one nucleotide from isolate BCVBV-UNB-01 (Alexandre et al 2016). However, the sequence size obtained by Alexandre et al (2016) was significantly shorter than ours and Rivas et al (2005), with only 396 bp or 32.25% of the total 1228 bp of the RT + RNase H region. Although the high pairwise identity of this region between BCVBV-UNB-01 and accession KF600737 would indicate they are both the same species, it is not necessarily the same virus, due to the lack of 2/3 of the recommended sequences.…”