Integration of banana streak badnavirus into the Musa genome: Molecular and cytogenetic evidence

Breeding and tissue culture of certain cultivars of bananas (Musa) have red to high levels of banana streak badnavirus (BSV) infection in progeny from symptomless parents. BSV DNA hybridized to genomic DNA of one such parent, Obino l'Ewai, suggesting integration of Viral sequences. Sequencing of cro nes of Obino l'Ewai genomic DNA revealed an interface between BSV and Musa sequences and a complex BSV integrant. In situ hybridization revealed two d ifferent BSV sequence locations in Obino l'Ewai chromosomes and a complex a rrangement of BSV and Muse sequences was shown by probing stretched DNA fib ers. This is the first report of integrated sequences that possibly lead to a plant pararetrovirus episomal infection by a mechanism differing markedl y from animal retroviral systems. (C) 1999 Academic Press.