Project description:Meristem culture and somatic embryogenesis is an effective tool for virus elimination of vegetatively propagated crops including grapevine. While they both are proved to be useful to eliminate the main grapevine viruses their efficiency differs according to the virus and the variety. In our work we investigated their efficiency using small RNA high-throughput sequencing as virus diagnostic method. Field grown mother plants of four clones representing three cultivars, infected with different viruses and viroids were selected for sanitation via somatic embryogenesis and meristem culture. Our results show that the sanitation with SE was efficient against all of the presenting viruses, including grapevine Pinot gris virus, grapevine rupestris vein feathering virus and grapevine Syrah virus 1, having no data using somatic embryogenesis for their elimination. In case of other viruses and viroids such as GFkV, GRSPaV, GYSVd-1, HSVd this study confirms the findings of earlier researches, that SE is a possible way for elimination. While the efficiency of the elimination of different viruses was high, in case of viroids this ratio was lower. Our work demonstrated that efficiency of SE is comparable to the technically difficult meristem culture technique, and show promising way for the high demand of the production of virus-free grapevine in the future.
Project description:Our experiments investigated the effects of various known chemotherapeutic agents (2-thiouracil, ribavirin and zidovudine) on grapevine for the elimination of several different viruses and viroids. Viruses and viroids were identified by small RNA HTS in the mother plants of different grapevine cultivars, and RT-PCR verified the results. Among the tested agents, ribavirin had the broadest elimination effect on most viruses. It proved to be particularly effective against GFkV, GLRaV-4, GPGV and GRSPaV, however, as a single treatment it was not able to eliminate GFLV. In our experiments, ribavirin also showed very low efficacy against GLRaV-1 and GVA viruses. The application of 2-TU caused high phytotoxicity, with only 25% efficacy against GLRaV-4 among the viruses tested. Zidovudine failed to eliminate any of the viruses we tested. However, the combination of ribavirin and zidovudine was able to eliminate GFLV, though with low efficacy (12.5%). In contrast, the combination of ribavirin and 2-TU has been shown to be very effective against GRSPaV and GPGV. Compared to ribavirin, zidovudine and 2-thiouracil did not demonstrate significant virus elimination efficacy in the case of tested viruses. In our experiments ribavirin could not remove HSVd and GYSVd-1 viroids. To the best of our knowledge, no prior studies have been published the successful use of ribavirin or other chemotherapeutic agents against GLRaV-4, and this is the first publication of a successful application of 2-TU and zidovudine against grape viruses .