Effect of Different Treatments on Producing in vitro Healthy Vitis vinifera L. cv. Halwani Free From Grapevine Leafroll-Associated Virus-3

El-Samin, M., K. El-Maari and F. El-Biski. 2022. Effect of Different Treatments on Producing in vitro Healthy Vitis vinifera L. cv. Halwani Free From Grapevine Leafroll-Associated Virus-3. Arab Journal of Plant Protection, 40(4): 334- 339. https://doi.org/10.22268/AJPP-40.4.334339 This study was carried out during the period 2020-2021, to produce virus-free propagation material from Halwani cultivar of grape infected with Grapevine leafroll-associated virus 3 (GLRaV-3), by using the meristem tip culture technique together with thermal and chemical treatments. The meristem tip of 500 micrometers was excised from infected plants and placed on 1/2 MS medium which contains 0.5 mg/l BAP and 30 g/l sucrose. Virus presence or absence was confirmed by the ELISA test (DAS-ELISA). Results showed that the highest Percentage of virus free plantlets (87.67%) was obtained from the combined treatment, whereas the thermal treatment resulted in the lowest percentage of virus-free plants (56.25%). The results obtained also showed the significant superiority of using meristem-tip culture compared with all other treatments in terms of percent growing plants, which reached 98.13%. This study indicated that there were negative effects of all treatments on plant elongation, especially the thermal treatment, which gave the least plant growth elongation (0.33 cm). Keywords: Grapevine leafroll-associated virus, grape, meristem, thermal treatment, chemical treatment, DAS-ELISA