Novel sugarcane streak and Sugarcane streak Réunion mastreviruses from southern Africa and La Réunion

Abstract

The sugarcane infecting streak viruses (SISVs) are mastreviruses (Family Geminiviridae) belonging to a group of "African streak viruses" (AfSVs) that includes the economically devastating Maize streak virus (MSV). Although there are three currently described SISV species (Sugarcane streak virus [SSV], Sugarcane streak Egypt virus [SSEV] and Sugarcane streak Réunion virus [SSRV]), only one strain variant has been fully sequenced for each of these species and as a result very little is known about the diversity and evolutionary origins of the SCISVs. Here we present annotated full genome sequences of four new SISV isolates, including a new strain of both SSRV and SSV, and one potentially new SISV species, sampled from wild grasses in La Réunion and Zimbabwe. For the first time, we report the finding of SSRV isolates in Zimbabwe and SSV isolates on the island of La Réunion. Phylogenetic and recombination analyses indicate continent-wide SSRV strain diversity and that our isolate potentially representing a new SISV species is a recombinant.