An oligonucleotide-based microarray for detection of plant RNA viruses

Currently, some of the methods used most widely for diagnosis and detection of plant viruses are ELISA, PCR, bioassays and electron microscopy. These methods only target one or a few species in each assay or they are time consuming and require expertise. Microarray-based approaches offer an alternative to these methods as microarrays with virus-specific probes could be capable of detecting an almost unlimited number of virus species in one assay. In the present study, the feasibility of this strategy was studied by constructing a microarray with 150 probes potentially capable of detecting 52 viruses from a broad range of genera. The array was printed in 16 subarrays to allow testing of several samples on each slide. Hybridizations with cDNA from plants infected with 52 different virus species showed that out of the 52 species tested, 49 were positive and identified correctly to species level. This array represents the largest published microarray for plant virus detection in terms of the number of targeted species and is thus an important milestone towards the construction of a generic microarray able to detect most, if not all, plant RNA viruses.