ABSTRACT
The late twentieth century saw a proliferation of new virus or virus-like discoveries. By 1996, ten previously unidentified sugarcane pathogens or diseases of significance to sugarcane quarantine were reported, with eight of those being known or suspected viruses (Croft, 1996). By 2000, seven viral diseases of sugarcane were officially recognized: Fiji disease (now Fiji leaf gall), mild mosaic, mosaic (caused by two viruses), red leaf mottle, streak, striate mosaic and the leaf fleck caused by bacilliform virus (Rott et al., 2000). Sugarcane streak mosaic virus (SCSMV) was only briefly alluded to, and Ramu stunt and sugarcane yellow leaf were not listed as viral diseases. Braithwaite (2001) discussed four new viruses in detail: peanut clump virus, sugarcane bacilliform virus (SCBV), sugarcane mild mosaic virus (SCMMV) and sugarcane yellow leaf virus (SCYLV), as they were considered to be the major emerging threats at the time. It is interesting to look at how sugarcane virology has progressed in the intervening years. While the pace of new discoveries has slowed, the range of molecular tools now available to researchers has expanded. This chapter will focus on the most researched sugarcane viruses in the past two decades and will describe the progress that has contributed to our understanding of those viruses.
