|Riassunto in Inglese:|
A DNA microarray chip was developed for screening 10 major economically important tomato viruses from infected plants using “Combimatrix” platform 40-mer oligonucleotide probes. A total of 279 oligonucleotide virus probes were specific for simultaneous multiple detection, identification, differentiation and/or genotyping of each of the following tomato RNA viruses and/or strains and a virus satellite: Cucumber mosaic virus, Cucumber mosaic virus satellite RNA, Tomato infectious chlorosis virus, Tomato chlorosis virus, Tomato spotted wilt virus, Pepino mosaic virus, Potato virus Y, Tobacco mosaic virus and Tomato mosaic virus. This selection included both positive and negative single-stranded RNA viruses. The single-stranded DNA viruses, Tomato yellow leaf curl virus and Tomato yellow leaf curl Sardinia virus were detected but were not differentiated using probes designed from their coat protein genes.
A sectored oligonucleotide microarray chip containing four sets of 2000 features (4 × 2K) was designed. In this way, four samples were tested simultaneously in a hybridization event and 16 samples were analyzed by re-using the chip four times. The hybrids had low background signals. Many of the 40-mer oligonucleotide probes were specific for the detection and identification of each RNA viral species, RNA viral satellite and genotyping strains of Cucumber mosaic virus, Pepino mosaic virus and Potato virus Y. Universal probes were developed for strains of the last three viruses and also for the genus Tobamovirus which includes both Tobacco mosaic virus and Tomato mosaic virus.