Pineapple bacilliform CO virus: Diversity, Detection, Distribution, and Transmission

Abstract

Members of the genus Badnavirus (family Caulimovirdae) have been identified in dicots and monocots worldwide. The genome of a pineapple badnavirus, designated Pineapple bacilliform CO virus-HI1 (PBCOV-HI1), and nine genomic variants (A through H) were isolated and sequenced from pineapple, Ananas comosus, in Hawaii. The 7,451-nucleotide genome of PBCOV-HI1 possesses three open reading frames (ORFs) encoding putative proteins of 20 (ORF1), 15 (ORF2), and 211 (ORF3) kDa. ORF3 encodes a polyprotein that includes a putative movement protein and viral aspartyl proteinase, reverse transcriptase, and RNase H regions. Three distinct groups of putative endogenous pineapple pararetroviral sequences and Metaviridae-like retrotransposons encoding long terminal repeat, reverse-transcriptase, RNase H, and integrase regions were also identified from the pineapple genome. Detection assays were developed to distinguish PBCOV-HI1 and genomic variants, putative endogenous pararetrovirus sequences, and Ananas Metaviridae sequences also identified in pineapple. PBCOV-HI1 incidences in two commercially grown pineapple hybrids, PRI 73-114 and PRI 73-50, was 34 to 68%. PBCOV-HI1 was transmitted by gray pineapple mealybugs, Dysmicoccus neobrevipes, to pineapple.