ABSTRACT
The feasibility of plant viral metagenomics became apparent in 2009, when two pioneering studies demonstrated that virus-derived small interfering RNA (siRNA) could be used to detect both known and previously uncharacterized plant viruses within infected plants (Donaire et al., 2009; Kreuze et al., 2009). Plant viral metagenomics quickly became popular, and many recent studies have discovered at least 86 unknown plant viruses (Roossinck et al., 2015). In 2010, a spatial plant virus metagenomics approach – also termed ‘ecogenomics’ – developed by M. Roossinck and coworkers, yielded geographically tagged cDNA sequences from known and unknown virus species (Roossinck et al., 2010). Besides describing many new viruses from uncultivated plants, ecogenomics studies have revealed that few wild plants infected by viruses displayed obvious evidence of virus infections at the time of sampling (Bernardo et al., 2013b; Muthukumar et al., 2009).
