10.46243/jst.2021.v6.i3.pp80-87 registered

In recent years, viral diseases have been developing strongly and causing significant damage to the yield and quality of tobacco in Vietnam such as TMV, CMV, and PVY. The objective of this study was to estimate the effective control of some antivirus agents and technical controls for the virus diseases on the tobacco plants. Two antivirus agents, Ditacin 8SL (Ningnanmycin) and Sat 4SL (Cytosinpeptidemycin) were performed in the net-house and field condition in Bac Giang province in 2019, Vietnam.The field experiment was arranged in a randomized complete block design with three replications.In net-house, a result of treating Ditacin 8SL from 3 to 6 times before infected plants had effective control of PVY with ranging from 24 - 33%; TMV: 28,9 - 50%; and CMV: 42,6 - 60% after 21 days of inoculation. For Sat 4SL, effective control of TMV ranged from 23,7 – 31,6%; CMV: 20,0 - 24,4% and PVY: 28,9 - 35,6% after 21 days of inoculation. In the field condition, the effective control of NNM was 100% for TMV; PVY: 93,5%; CMV: 60,5% and TNRV: 52,1%. Similar to Ditacin 8SL, treating Sat 4SL, the effective control of TMV reached 70,9%; CMV: 58,3%; PVY: 96,4% and TNRV: 36,9%. Spraying Ditacin 8SL and Sat 4SL in the stage from transplanting (3 - 4 leaves/plant) to 16 - 18 leaves/plant were the best control of viral diseases, increased the yield, grade index, and less impact on the property of smoke. Our conclusions showed the Ditacin 8SL and Sat 4SL were effective in controlling TMV, CMV, PVY, and TNRV on tobacco plants. To effectively manage virus diseases of CMV, PVY, and TNRV, have to spray a mixture of virucide, insecticide, and foliar fertilizer, with TMV only uses the virucide and foliar fertilizer, and destroy all disease plants.