Specific Aim 2: Characterize bottlenecks that limit CMB diversity
 
Two likely bottlenecks of CMB evolution are viral movement in cassava and whitefly transmission. To examine movement, inoculated leaves and upper leaves infected by systemic movement of the virus will be surveyed for CMB diversity by NGS. We will ask if cell-to-cell movement in the inoculated leaf is a bottleneck by comparing evolution of the autonomously replicating DNA-A alone or in the presence of DNA-B, which is required for movement.